diff options
Diffstat (limited to 'Documentation')
58 files changed, 2721 insertions, 584 deletions
diff --git a/Documentation/Changes b/Documentation/Changes index 86b86399d61d72..fe5ae0f550202f 100644 --- a/Documentation/Changes +++ b/Documentation/Changes @@ -31,8 +31,6 @@ al espaņol de este documento en varios formatos. Eine deutsche Version dieser Datei finden Sie unter <http://www.stefan-winter.de/Changes-2.4.0.txt>. -Last updated: October 29th, 2002 - Chris Ricker (kaboom@gatech.edu or chris.ricker@genetics.utah.edu). Current Minimal Requirements @@ -48,7 +46,7 @@ necessary on all systems; obviously, if you don't have any ISDN hardware, for example, you probably needn't concern yourself with isdn4k-utils. -o Gnu C 2.95.3 # gcc --version +o Gnu C 3.2 # gcc --version o Gnu make 3.79.1 # make --version o binutils 2.12 # ld -v o util-linux 2.10o # fdformat --version @@ -74,26 +72,7 @@ GCC --- The gcc version requirements may vary depending on the type of CPU in your -computer. The next paragraph applies to users of x86 CPUs, but not -necessarily to users of other CPUs. Users of other CPUs should obtain -information about their gcc version requirements from another source. - -The recommended compiler for the kernel is gcc 2.95.x (x >= 3), and it -should be used when you need absolute stability. You may use gcc 3.0.x -instead if you wish, although it may cause problems. Later versions of gcc -have not received much testing for Linux kernel compilation, and there are -almost certainly bugs (mainly, but not exclusively, in the kernel) that -will need to be fixed in order to use these compilers. In any case, using -pgcc instead of plain gcc is just asking for trouble. - -The Red Hat gcc 2.96 compiler subtree can also be used to build this tree. -You should ensure you use gcc-2.96-74 or later. gcc-2.96-54 will not build -the kernel correctly. - -In addition, please pay attention to compiler optimization. Anything -greater than -O2 may not be wise. Similarly, if you choose to use gcc-2.95.x -or derivatives, be sure not to use -fstrict-aliasing (which, depending on -your version of gcc 2.95.x, may necessitate using -fno-strict-aliasing). +computer. Make ---- @@ -322,9 +301,9 @@ Getting updated software Kernel compilation ****************** -gcc 2.95.3 ----------- -o <ftp://ftp.gnu.org/gnu/gcc/gcc-2.95.3.tar.gz> +gcc +--- +o <ftp://ftp.gnu.org/gnu/gcc/> Make ---- diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index eb7db3c192273a..ce5d2c038cf546 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -199,7 +199,7 @@ The rationale is: modifications are prevented - saves the compiler work to optimize redundant code away ;) -int fun(int ) +int fun(int a) { int result = 0; char *buffer = kmalloc(SIZE); @@ -344,7 +344,7 @@ Remember: if another thread can find your data structure, and you don't have a reference count on it, you almost certainly have a bug. - Chapter 11: Macros, Enums, Inline functions and RTL + Chapter 11: Macros, Enums and RTL Names of macros defining constants and labels in enums are capitalized. @@ -429,7 +429,35 @@ from void pointer to any other pointer type is guaranteed by the C programming language. - Chapter 14: References + Chapter 14: The inline disease + +There appears to be a common misperception that gcc has a magic "make me +faster" speedup option called "inline". While the use of inlines can be +appropriate (for example as a means of replacing macros, see Chapter 11), it +very often is not. Abundant use of the inline keyword leads to a much bigger +kernel, which in turn slows the system as a whole down, due to a bigger +icache footprint for the CPU and simply because there is less memory +available for the pagecache. Just think about it; a pagecache miss causes a +disk seek, which easily takes 5 miliseconds. There are a LOT of cpu cycles +that can go into these 5 miliseconds. + +A reasonable rule of thumb is to not put inline at functions that have more +than 3 lines of code in them. An exception to this rule are the cases where +a parameter is known to be a compiletime constant, and as a result of this +constantness you *know* the compiler will be able to optimize most of your +function away at compile time. For a good example of this later case, see +the kmalloc() inline function. + +Often people argue that adding inline to functions that are static and used +only once is always a win since there is no space tradeoff. While this is +technically correct, gcc is capable of inlining these automatically without +help, and the maintenance issue of removing the inline when a second user +appears outweighs the potential value of the hint that tells gcc to do +something it would have done anyway. + + + + Chapter 15: References The C Programming Language, Second Edition by Brian W. Kernighan and Dennis M. Ritchie. @@ -444,10 +472,13 @@ ISBN 0-201-61586-X. URL: http://cm.bell-labs.com/cm/cs/tpop/ GNU manuals - where in compliance with K&R and this text - for cpp, gcc, -gcc internals and indent, all available from http://www.gnu.org +gcc internals and indent, all available from http://www.gnu.org/manual/ WG14 is the international standardization working group for the programming -language C, URL: http://std.dkuug.dk/JTC1/SC22/WG14/ +language C, URL: http://www.open-std.org/JTC1/SC22/WG14/ + +Kernel CodingStyle, by greg@kroah.com at OLS 2002: +http://www.kroah.com/linux/talks/ols_2002_kernel_codingstyle_talk/html/ -- -Last updated on 16 February 2004 by a community effort on LKML. +Last updated on 30 December 2005 by a community effort on LKML. diff --git a/Documentation/DocBook/.gitignore b/Documentation/DocBook/.gitignore new file mode 100644 index 00000000000000..c102c02ecf8960 --- /dev/null +++ b/Documentation/DocBook/.gitignore @@ -0,0 +1,6 @@ +*.xml +*.ps +*.pdf +*.html +*.9.gz +*.9 diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index 767433bdbc4099..8c9c6704e85bab 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -54,6 +54,11 @@ !Ekernel/sched.c !Ekernel/timer.c </sect1> + <sect1><title>High-resolution timers</title> +!Iinclude/linux/ktime.h +!Iinclude/linux/hrtimer.h +!Ekernel/hrtimer.c + </sect1> <sect1><title>Internal Functions</title> !Ikernel/exit.c !Ikernel/signal.c @@ -369,6 +374,7 @@ X!Edrivers/acpi/motherboard.c X!Edrivers/acpi/bus.c --> !Edrivers/acpi/scan.c +!Idrivers/acpi/scan.c <!-- No correct structured comments X!Edrivers/acpi/pci_bind.c --> diff --git a/Documentation/DocBook/kernel-locking.tmpl b/Documentation/DocBook/kernel-locking.tmpl index 90dc2de8e0afd9..158ffe9bfadee2 100644 --- a/Documentation/DocBook/kernel-locking.tmpl +++ b/Documentation/DocBook/kernel-locking.tmpl @@ -222,7 +222,7 @@ <title>Two Main Types of Kernel Locks: Spinlocks and Semaphores</title> <para> - There are two main types of kernel locks. The fundamental type + There are three main types of kernel locks. The fundamental type is the spinlock (<filename class="headerfile">include/asm/spinlock.h</filename>), which is a very simple single-holder lock: if you can't get the @@ -230,16 +230,22 @@ very small and fast, and can be used anywhere. </para> <para> - The second type is a semaphore + The second type is a mutex + (<filename class="headerfile">include/linux/mutex.h</filename>): it + is like a spinlock, but you may block holding a mutex. + If you can't lock a mutex, your task will suspend itself, and be woken + up when the mutex is released. This means the CPU can do something + else while you are waiting. There are many cases when you simply + can't sleep (see <xref linkend="sleeping-things"/>), and so have to + use a spinlock instead. + </para> + <para> + The third type is a semaphore (<filename class="headerfile">include/asm/semaphore.h</filename>): it can have more than one holder at any time (the number decided at initialization time), although it is most commonly used as a - single-holder lock (a mutex). If you can't get a semaphore, - your task will put itself on the queue, and be woken up when the - semaphore is released. This means the CPU will do something - else while you are waiting, but there are many cases when you - simply can't sleep (see <xref linkend="sleeping-things"/>), and so - have to use a spinlock instead. + single-holder lock (a mutex). If you can't get a semaphore, your + task will be suspended and later on woken up - just like for mutexes. </para> <para> Neither type of lock is recursive: see diff --git a/Documentation/RCU/rcuref.txt b/Documentation/RCU/rcuref.txt index a23fee66064df4..3f60db41b2f0fd 100644 --- a/Documentation/RCU/rcuref.txt +++ b/Documentation/RCU/rcuref.txt @@ -1,74 +1,67 @@ -Refcounter framework for elements of lists/arrays protected by -RCU. +Refcounter design for elements of lists/arrays protected by RCU. Refcounting on elements of lists which are protected by traditional reader/writer spinlocks or semaphores are straight forward as in: -1. 2. -add() search_and_reference() -{ { - alloc_object read_lock(&list_lock); - ... search_for_element - atomic_set(&el->rc, 1); atomic_inc(&el->rc); - write_lock(&list_lock); ... - add_element read_unlock(&list_lock); - ... ... - write_unlock(&list_lock); } +1. 2. +add() search_and_reference() +{ { + alloc_object read_lock(&list_lock); + ... search_for_element + atomic_set(&el->rc, 1); atomic_inc(&el->rc); + write_lock(&list_lock); ... + add_element read_unlock(&list_lock); + ... ... + write_unlock(&list_lock); } } 3. 4. release_referenced() delete() { { - ... write_lock(&list_lock); - atomic_dec(&el->rc, relfunc) ... - ... delete_element -} write_unlock(&list_lock); - ... - if (atomic_dec_and_test(&el->rc)) - kfree(el); - ... + ... write_lock(&list_lock); + atomic_dec(&el->rc, relfunc) ... + ... delete_element +} write_unlock(&list_lock); + ... + if (atomic_dec_and_test(&el->rc)) + kfree(el); + ... } If this list/array is made lock free using rcu as in changing the write_lock in add() and delete() to spin_lock and changing read_lock -in search_and_reference to rcu_read_lock(), the rcuref_get in +in search_and_reference to rcu_read_lock(), the atomic_get in search_and_reference could potentially hold reference to an element which -has already been deleted from the list/array. rcuref_lf_get_rcu takes +has already been deleted from the list/array. atomic_inc_not_zero takes care of this scenario. search_and_reference should look as; 1. 2. add() search_and_reference() { { - alloc_object rcu_read_lock(); - ... search_for_element - atomic_set(&el->rc, 1); if (rcuref_inc_lf(&el->rc)) { - write_lock(&list_lock); rcu_read_unlock(); - return FAIL; - add_element } - ... ... - write_unlock(&list_lock); rcu_read_unlock(); + alloc_object rcu_read_lock(); + ... search_for_element + atomic_set(&el->rc, 1); if (atomic_inc_not_zero(&el->rc)) { + write_lock(&list_lock); rcu_read_unlock(); + return FAIL; + add_element } + ... ... + write_unlock(&list_lock); rcu_read_unlock(); } } 3. 4. release_referenced() delete() { { - ... write_lock(&list_lock); - rcuref_dec(&el->rc, relfunc) ... - ... delete_element -} write_unlock(&list_lock); - ... - if (rcuref_dec_and_test(&el->rc)) - call_rcu(&el->head, el_free); - ... + ... write_lock(&list_lock); + atomic_dec(&el->rc, relfunc) ... + ... delete_element +} write_unlock(&list_lock); + ... + if (atomic_dec_and_test(&el->rc)) + call_rcu(&el->head, el_free); + ... } Sometimes, reference to the element need to be obtained in the -update (write) stream. In such cases, rcuref_inc_lf might be an overkill -since the spinlock serialising list updates are held. rcuref_inc +update (write) stream. In such cases, atomic_inc_not_zero might be an +overkill since the spinlock serialising list updates are held. atomic_inc is to be used in such cases. -For arches which do not have cmpxchg rcuref_inc_lf -api uses a hashed spinlock implementation and the same hashed spinlock -is acquired in all rcuref_xxx primitives to preserve atomicity. -Note: Use rcuref_inc api only if you need to use rcuref_inc_lf on the -refcounter atleast at one place. Mixing rcuref_inc and atomic_xxx api -might lead to races. rcuref_inc_lf() must be used in lockfree -RCU critical sections only. + diff --git a/Documentation/SubmittingDrivers b/Documentation/SubmittingDrivers index c3cca924e94b4a..dd311cff1cc30b 100644 --- a/Documentation/SubmittingDrivers +++ b/Documentation/SubmittingDrivers @@ -27,18 +27,17 @@ Who To Submit Drivers To ------------------------ Linux 2.0: - No new drivers are accepted for this kernel tree + No new drivers are accepted for this kernel tree. Linux 2.2: + No new drivers are accepted for this kernel tree. + +Linux 2.4: If the code area has a general maintainer then please submit it to the maintainer listed in MAINTAINERS in the kernel file. If the maintainer does not respond or you cannot find the appropriate - maintainer then please contact the 2.2 kernel maintainer: - Marc-Christian Petersen <m.c.p@wolk-project.de>. - -Linux 2.4: - The same rules apply as 2.2. The final contact point for Linux 2.4 - submissions is Marcelo Tosatti <marcelo.tosatti@cyclades.com>. + maintainer then please contact Marcelo Tosatti + <marcelo.tosatti@cyclades.com>. Linux 2.6: The same rules apply as 2.4 except that you should follow linux-kernel @@ -53,6 +52,7 @@ Licensing: The code must be released to us under the of exclusive GPL licensing, and if you wish the driver to be useful to other communities such as BSD you may well wish to release under multiple licenses. + See accepted licenses at include/linux/module.h Copyright: The copyright owner must agree to use of GPL. It's best if the submitter and copyright owner @@ -143,5 +143,13 @@ KernelNewbies: http://kernelnewbies.org/ Linux USB project: - http://sourceforge.net/projects/linux-usb/ + http://linux-usb.sourceforge.net/ + +How to NOT write kernel driver by arjanv@redhat.com + http://people.redhat.com/arjanv/olspaper.pdf + +Kernel Janitor: + http://janitor.kernelnewbies.org/ +-- +Last updated on 17 Nov 2005. diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches index 1d47e6c09dc60c..6198e5ebcf65be 100644 --- a/Documentation/SubmittingPatches +++ b/Documentation/SubmittingPatches @@ -78,7 +78,9 @@ Randy Dunlap's patch scripts: http://www.xenotime.net/linux/scripts/patching-scripts-002.tar.gz Andrew Morton's patch scripts: -http://www.zip.com.au/~akpm/linux/patches/patch-scripts-0.20 +http://www.zip.com.au/~akpm/linux/patches/ +Instead of these scripts, quilt is the recommended patch management +tool (see above). @@ -97,7 +99,7 @@ need to split up your patch. See #3, next. 3) Separate your changes. -Separate each logical change into its own patch. +Separate _logical changes_ into a single patch file. For example, if your changes include both bug fixes and performance enhancements for a single driver, separate those changes into two @@ -112,6 +114,10 @@ If one patch depends on another patch in order for a change to be complete, that is OK. Simply note "this patch depends on patch X" in your patch description. +If you cannot condense your patch set into a smaller set of patches, +then only post say 15 or so at a time and wait for review and integration. + + 4) Select e-mail destination. @@ -124,6 +130,10 @@ your patch to the primary Linux kernel developer's mailing list, linux-kernel@vger.kernel.org. Most kernel developers monitor this e-mail list, and can comment on your changes. + +Do not send more than 15 patches at once to the vger mailing lists!!! + + Linus Torvalds is the final arbiter of all changes accepted into the Linux kernel. His e-mail address is <torvalds@osdl.org>. He gets a lot of e-mail, so typically you should do your best to -avoid- sending @@ -149,6 +159,9 @@ USB, framebuffer devices, the VFS, the SCSI subsystem, etc. See the MAINTAINERS file for a mailing list that relates specifically to your change. +Majordomo lists of VGER.KERNEL.ORG at: + <http://vger.kernel.org/vger-lists.html> + If changes affect userland-kernel interfaces, please send the MAN-PAGES maintainer (as listed in the MAINTAINERS file) a man-pages patch, or at least a notification of the change, @@ -373,27 +386,14 @@ a diffstat, to show what files have changed, and the number of inserted and deleted lines per file. A diffstat is especially useful on bigger patches. Other comments relevant only to the moment or the maintainer, not suitable for the permanent changelog, should also go here. +Use diffstat options "-p 1 -w 70" so that filenames are listed from the +top of the kernel source tree and don't use too much horizontal space +(easily fit in 80 columns, maybe with some indentation). See more details on the proper patch format in the following references. -13) More references for submitting patches - -Andrew Morton, "The perfect patch" (tpp). - <http://www.zip.com.au/~akpm/linux/patches/stuff/tpp.txt> - -Jeff Garzik, "Linux kernel patch submission format." - <http://linux.yyz.us/patch-format.html> - -Greg KH, "How to piss off a kernel subsystem maintainer" - <http://www.kroah.com/log/2005/03/31/> - -Kernel Documentation/CodingStyle - <http://sosdg.org/~coywolf/lxr/source/Documentation/CodingStyle> - -Linus Torvald's mail on the canonical patch format: - <http://lkml.org/lkml/2005/4/7/183> ----------------------------------- @@ -466,3 +466,30 @@ and 'extern __inline__'. Don't try to anticipate nebulous future cases which may or may not be useful: "Make it as simple as you can, and no simpler." + + +---------------------- +SECTION 3 - REFERENCES +---------------------- + +Andrew Morton, "The perfect patch" (tpp). + <http://www.zip.com.au/~akpm/linux/patches/stuff/tpp.txt> + +Jeff Garzik, "Linux kernel patch submission format." + <http://linux.yyz.us/patch-format.html> + +Greg Kroah, "How to piss off a kernel subsystem maintainer". + <http://www.kroah.com/log/2005/03/31/> + <http://www.kroah.com/log/2005/07/08/> + <http://www.kroah.com/log/2005/10/19/> + +NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people!. + <http://marc.theaimsgroup.com/?l=linux-kernel&m=112112749912944&w=2> + +Kernel Documentation/CodingStyle + <http://sosdg.org/~coywolf/lxr/source/Documentation/CodingStyle> + +Linus Torvald's mail on the canonical patch format: + <http://lkml.org/lkml/2005/4/7/183> +-- +Last updated on 17 Nov 2005. diff --git a/Documentation/applying-patches.txt b/Documentation/applying-patches.txt index 681e426e248210..a083ba35d1adf8 100644 --- a/Documentation/applying-patches.txt +++ b/Documentation/applying-patches.txt @@ -2,8 +2,8 @@ Applying Patches To The Linux Kernel ------------------------------------ - (Written by Jesper Juhl, August 2005) - + Original by: Jesper Juhl, August 2005 + Last update: 2006-01-05 A frequently asked question on the Linux Kernel Mailing List is how to apply @@ -76,7 +76,7 @@ instead: If you wish to uncompress the patch file by hand first before applying it (what I assume you've done in the examples below), then you simply run -gunzip or bunzip2 on the file - like this: +gunzip or bunzip2 on the file -- like this: gunzip patch-x.y.z.gz bunzip2 patch-x.y.z.bz2 @@ -94,7 +94,7 @@ Common errors when patching --- When patch applies a patch file it attempts to verify the sanity of the file in different ways. -Checking that the file looks like a valid patch file, checking the code +Checking that the file looks like a valid patch file & checking the code around the bits being modified matches the context provided in the patch are just two of the basic sanity checks patch does. @@ -118,16 +118,16 @@ wrong. When patch encounters a change that it can't fix up with fuzz it rejects it outright and leaves a file with a .rej extension (a reject file). You can -read this file to see exactely what change couldn't be applied, so you can +read this file to see exactly what change couldn't be applied, so you can go fix it up by hand if you wish. -If you don't have any third party patches applied to your kernel source, but +If you don't have any third-party patches applied to your kernel source, but only patches from kernel.org and you apply the patches in the correct order, and have made no modifications yourself to the source files, then you should never see a fuzz or reject message from patch. If you do see such messages anyway, then there's a high risk that either your local source tree or the patch file is corrupted in some way. In that case you should probably try -redownloading the patch and if things are still not OK then you'd be advised +re-downloading the patch and if things are still not OK then you'd be advised to start with a fresh tree downloaded in full from kernel.org. Let's look a bit more at some of the messages patch can produce. @@ -136,7 +136,7 @@ If patch stops and presents a "File to patch:" prompt, then patch could not find a file to be patched. Most likely you forgot to specify -p1 or you are in the wrong directory. Less often, you'll find patches that need to be applied with -p0 instead of -p1 (reading the patch file should reveal if -this is the case - if so, then this is an error by the person who created +this is the case -- if so, then this is an error by the person who created the patch but is not fatal). If you get "Hunk #2 succeeded at 1887 with fuzz 2 (offset 7 lines)." or a @@ -167,22 +167,28 @@ the patch will in fact apply it. A message similar to "patch: **** unexpected end of file in patch" or "patch unexpectedly ends in middle of line" means that patch could make no sense of -the file you fed to it. Either your download is broken or you tried to feed -patch a compressed patch file without uncompressing it first. +the file you fed to it. Either your download is broken, you tried to feed +patch a compressed patch file without uncompressing it first, or the patch +file that you are using has been mangled by a mail client or mail transfer +agent along the way somewhere, e.g., by splitting a long line into two lines. +Often these warnings can easily be fixed by joining (concatenating) the +two lines that had been split. As I already mentioned above, these errors should never happen if you apply a patch from kernel.org to the correct version of an unmodified source tree. So if you get these errors with kernel.org patches then you should probably -assume that either your patch file or your tree is broken and I'd advice you +assume that either your patch file or your tree is broken and I'd advise you to start over with a fresh download of a full kernel tree and the patch you wish to apply. Are there any alternatives to `patch'? --- - Yes there are alternatives. You can use the `interdiff' program -(http://cyberelk.net/tim/patchutils/) to generate a patch representing the -differences between two patches and then apply the result. + Yes there are alternatives. + + You can use the `interdiff' program (http://cyberelk.net/tim/patchutils/) to +generate a patch representing the differences between two patches and then +apply the result. This will let you move from something like 2.6.12.2 to 2.6.12.3 in a single step. The -z flag to interdiff will even let you feed it patches in gzip or bzip2 compressed form directly without the use of zcat or bzcat or manual @@ -197,10 +203,10 @@ do the additional steps since interdiff can get things wrong in some cases. Another alternative is `ketchup', which is a python script for automatic downloading and applying of patches (http://www.selenic.com/ketchup/). -Other nice tools are diffstat which shows a summary of changes made by a -patch, lsdiff which displays a short listing of affected files in a patch -file, along with (optionally) the line numbers of the start of each patch -and grepdiff which displays a list of the files modified by a patch where + Other nice tools are diffstat, which shows a summary of changes made by a +patch; lsdiff, which displays a short listing of affected files in a patch +file, along with (optionally) the line numbers of the start of each patch; +and grepdiff, which displays a list of the files modified by a patch where the patch contains a given regular expression. @@ -225,8 +231,8 @@ The -mm kernels live at In place of ftp.kernel.org you can use ftp.cc.kernel.org, where cc is a country code. This way you'll be downloading from a mirror site that's most likely geographically closer to you, resulting in faster downloads for you, -less bandwidth used globally and less load on the main kernel.org servers - -these are good things, do use mirrors when possible. +less bandwidth used globally and less load on the main kernel.org servers -- +these are good things, so do use mirrors when possible. The 2.6.x kernels @@ -234,14 +240,14 @@ The 2.6.x kernels These are the base stable releases released by Linus. The highest numbered release is the most recent. -If regressions or other serious flaws are found then a -stable fix patch +If regressions or other serious flaws are found, then a -stable fix patch will be released (see below) on top of this base. Once a new 2.6.x base kernel is released, a patch is made available that is a delta between the previous 2.6.x kernel and the new one. -To apply a patch moving from 2.6.11 to 2.6.12 you'd do the following (note +To apply a patch moving from 2.6.11 to 2.6.12, you'd do the following (note that such patches do *NOT* apply on top of 2.6.x.y kernels but on top of the -base 2.6.x kernel - if you need to move from 2.6.x.y to 2.6.x+1 you need to +base 2.6.x kernel -- if you need to move from 2.6.x.y to 2.6.x+1 you need to first revert the 2.6.x.y patch). Here are some examples: @@ -258,12 +264,12 @@ $ patch -p1 -R < ../patch-2.6.11.1 # revert the 2.6.11.1 patch # source dir is now 2.6.11 $ patch -p1 < ../patch-2.6.12 # apply new 2.6.12 patch $ cd .. -$ mv linux-2.6.11.1 inux-2.6.12 # rename source dir +$ mv linux-2.6.11.1 linux-2.6.12 # rename source dir The 2.6.x.y kernels --- - Kernels with 4 digit versions are -stable kernels. They contain small(ish) + Kernels with 4-digit versions are -stable kernels. They contain small(ish) critical fixes for security problems or significant regressions discovered in a given 2.6.x kernel. @@ -274,9 +280,14 @@ versions. If no 2.6.x.y kernel is available, then the highest numbered 2.6.x kernel is the current stable kernel. + note: the -stable team usually do make incremental patches available as well + as patches against the latest mainline release, but I only cover the + non-incremental ones below. The incremental ones can be found at + ftp://ftp.kernel.org/pub/linux/kernel/v2.6/incr/ + These patches are not incremental, meaning that for example the 2.6.12.3 patch does not apply on top of the 2.6.12.2 kernel source, but rather on top -of the base 2.6.12 kernel source. +of the base 2.6.12 kernel source . So, in order to apply the 2.6.12.3 patch to your existing 2.6.12.2 kernel source you have to first back out the 2.6.12.2 patch (so you are left with a base 2.6.12 kernel source) and then apply the new 2.6.12.3 patch. @@ -342,12 +353,12 @@ The -git kernels repository, hence the name). These patches are usually released daily and represent the current state of -Linus' tree. They are more experimental than -rc kernels since they are +Linus's tree. They are more experimental than -rc kernels since they are generated automatically without even a cursory glance to see if they are sane. -git patches are not incremental and apply either to a base 2.6.x kernel or -a base 2.6.x-rc kernel - you can see which from their name. +a base 2.6.x-rc kernel -- you can see which from their name. A patch named 2.6.12-git1 applies to the 2.6.12 kernel source and a patch named 2.6.13-rc3-git2 applies to the source of the 2.6.13-rc3 kernel. @@ -390,12 +401,12 @@ You should generally strive to get your patches into mainline via -mm to ensure maximum testing. This branch is in constant flux and contains many experimental features, a -lot of debugging patches not appropriate for mainline etc and is the most +lot of debugging patches not appropriate for mainline etc., and is the most experimental of the branches described in this document. These kernels are not appropriate for use on systems that are supposed to be stable and they are more risky to run than any of the other branches (make -sure you have up-to-date backups - that goes for any experimental kernel but +sure you have up-to-date backups -- that goes for any experimental kernel but even more so for -mm kernels). These kernels in addition to all the other experimental patches they contain @@ -433,7 +444,11 @@ $ cd .. $ mv linux-2.6.12-mm1 linux-2.6.13-rc3-mm3 # rename the source dir -This concludes this list of explanations of the various kernel trees and I -hope you are now crystal clear on how to apply the various patches and help -testing the kernel. +This concludes this list of explanations of the various kernel trees. +I hope you are now clear on how to apply the various patches and help testing +the kernel. + +Thank you's to Randy Dunlap, Rolf Eike Beer, Linus Torvalds, Bodo Eggert, +Johannes Stezenbach, Grant Coady, Pavel Machek and others that I may have +forgotten for their reviews and contributions to this document. diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt index 303c57a7fad952..8e63831971d5e4 100644 --- a/Documentation/block/biodoc.txt +++ b/Documentation/block/biodoc.txt @@ -263,14 +263,8 @@ A flag in the bio structure, BIO_BARRIER is used to identify a barrier i/o. The generic i/o scheduler would make sure that it places the barrier request and all other requests coming after it after all the previous requests in the queue. Barriers may be implemented in different ways depending on the -driver. A SCSI driver for example could make use of ordered tags to -preserve the necessary ordering with a lower impact on throughput. For IDE -this might be two sync cache flush: a pre and post flush when encountering -a barrier write. - -There is a provision for queues to indicate what kind of barriers they -can provide. This is as of yet unmerged, details will be added here once it -is in the kernel. +driver. For more details regarding I/O barriers, please read barrier.txt +in this directory. 1.2.2 Request Priority/Latency diff --git a/Documentation/block/stat.txt b/Documentation/block/stat.txt new file mode 100644 index 00000000000000..0dbc946de2eab8 --- /dev/null +++ b/Documentation/block/stat.txt @@ -0,0 +1,82 @@ +Block layer statistics in /sys/block/<dev>/stat +=============================================== + +This file documents the contents of the /sys/block/<dev>/stat file. + +The stat file provides several statistics about the state of block +device <dev>. + +Q. Why are there multiple statistics in a single file? Doesn't sysfs + normally contain a single value per file? +A. By having a single file, the kernel can guarantee that the statistics + represent a consistent snapshot of the state of the device. If the + statistics were exported as multiple files containing one statistic + each, it would be impossible to guarantee that a set of readings + represent a single point in time. + +The stat file consists of a single line of text containing 11 decimal +values separated by whitespace. The fields are summarized in the +following table, and described in more detail below. + +Name units description +---- ----- ----------- +read I/Os requests number of read I/Os processed +read merges requests number of read I/Os merged with in-queue I/O +read sectors sectors number of sectors read +read ticks milliseconds total wait time for read requests +write I/Os requests number of write I/Os processed +write merges requests number of write I/Os merged with in-queue I/O +write sectors sectors number of sectors written +write ticks milliseconds total wait time for write requests +in_flight requests number of I/Os currently in flight +io_ticks milliseconds total time this block device has been active +time_in_queue milliseconds total wait time for all requests + +read I/Os, write I/Os +===================== + +These values increment when an I/O request completes. + +read merges, write merges +========================= + +These values increment when an I/O request is merged with an +already-queued I/O request. + +read sectors, write sectors +=========================== + +These values count the number of sectors read from or written to this +block device. The "sectors" in question are the standard UNIX 512-byte +sectors, not any device- or filesystem-specific block size. The +counters are incremented when the I/O completes. + +read ticks, write ticks +======================= + +These values count the number of milliseconds that I/O requests have +waited on this block device. If there are multiple I/O requests waiting, +these values will increase at a rate greater than 1000/second; for +example, if 60 read requests wait for an average of 30 ms, the read_ticks +field will increase by 60*30 = 1800. + +in_flight +========= + +This value counts the number of I/O requests that have been issued to +the device driver but have not yet completed. It does not include I/O +requests that are in the queue but not yet issued to the device driver. + +io_ticks +======== + +This value counts the number of milliseconds during which the device has +had I/O requests queued. + +time_in_queue +============= + +This value counts the number of milliseconds that I/O requests have waited +on this block device. If there are multiple I/O requests waiting, this +value will increase as the product of the number of milliseconds times the +number of requests waiting (see "read ticks" above for an example). diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt new file mode 100644 index 00000000000000..08c5d04f308600 --- /dev/null +++ b/Documentation/cpu-hotplug.txt @@ -0,0 +1,357 @@ + CPU hotplug Support in Linux(tm) Kernel + + Maintainers: + CPU Hotplug Core: + Rusty Russell <rusty@rustycorp.com.au> + Srivatsa Vaddagiri <vatsa@in.ibm.com> + i386: + Zwane Mwaikambo <zwane@arm.linux.org.uk> + ppc64: + Nathan Lynch <nathanl@austin.ibm.com> + Joel Schopp <jschopp@austin.ibm.com> + ia64/x86_64: + Ashok Raj <ashok.raj@intel.com> + +Authors: Ashok Raj <ashok.raj@intel.com> +Lots of feedback: Nathan Lynch <nathanl@austin.ibm.com>, + Joel Schopp <jschopp@austin.ibm.com> + +Introduction + +Modern advances in system architectures have introduced advanced error +reporting and correction capabilities in processors. CPU architectures permit +partitioning support, where compute resources of a single CPU could be made +available to virtual machine environments. There are couple OEMS that +support NUMA hardware which are hot pluggable as well, where physical +node insertion and removal require support for CPU hotplug. + +Such advances require CPUs available to a kernel to be removed either for +provisioning reasons, or for RAS purposes to keep an offending CPU off +system execution path. Hence the need for CPU hotplug support in the +Linux kernel. + +A more novel use of CPU-hotplug support is its use today in suspend +resume support for SMP. Dual-core and HT support makes even +a laptop run SMP kernels which didn't support these methods. SMP support +for suspend/resume is a work in progress. + +General Stuff about CPU Hotplug +-------------------------------- + +Command Line Switches +--------------------- +maxcpus=n Restrict boot time cpus to n. Say if you have 4 cpus, using + maxcpus=2 will only boot 2. You can choose to bring the + other cpus later online, read FAQ's for more info. + +additional_cpus=n [x86_64 only] use this to limit hotpluggable cpus. + This option sets + cpu_possible_map = cpu_present_map + additional_cpus + +CPU maps and such +----------------- +[More on cpumaps and primitive to manipulate, please check +include/linux/cpumask.h that has more descriptive text.] + +cpu_possible_map: Bitmap of possible CPUs that can ever be available in the +system. This is used to allocate some boot time memory for per_cpu variables +that aren't designed to grow/shrink as CPUs are made available or removed. +Once set during boot time discovery phase, the map is static, i.e no bits +are added or removed anytime. Trimming it accurately for your system needs +upfront can save some boot time memory. See below for how we use heuristics +in x86_64 case to keep this under check. + +cpu_online_map: Bitmap of all CPUs currently online. Its set in __cpu_up() +after a cpu is available for kernel scheduling and ready to receive +interrupts from devices. Its cleared when a cpu is brought down using +__cpu_disable(), before which all OS services including interrupts are +migrated to another target CPU. + +cpu_present_map: Bitmap of CPUs currently present in the system. Not all +of them may be online. When physical hotplug is processed by the relevant +subsystem (e.g ACPI) can change and new bit either be added or removed +from the map depending on the event is hot-add/hot-remove. There are currently +no locking rules as of now. Typical usage is to init topology during boot, +at which time hotplug is disabled. + +You really dont need to manipulate any of the system cpu maps. They should +be read-only for most use. When setting up per-cpu resources almost always use +cpu_possible_map/for_each_cpu() to iterate. + +Never use anything other than cpumask_t to represent bitmap of CPUs. + +#include <linux/cpumask.h> + +for_each_cpu - Iterate over cpu_possible_map +for_each_online_cpu - Iterate over cpu_online_map +for_each_present_cpu - Iterate over cpu_present_map +for_each_cpu_mask(x,mask) - Iterate over some random collection of cpu mask. + +#include <linux/cpu.h> +lock_cpu_hotplug() and unlock_cpu_hotplug(): + +The above calls are used to inhibit cpu hotplug operations. While holding the +cpucontrol mutex, cpu_online_map will not change. If you merely need to avoid +cpus going away, you could also use preempt_disable() and preempt_enable() +for those sections. Just remember the critical section cannot call any +function that can sleep or schedule this process away. The preempt_disable() +will work as long as stop_machine_run() is used to take a cpu down. + +CPU Hotplug - Frequently Asked Questions. + +Q: How to i enable my kernel to support CPU hotplug? +A: When doing make defconfig, Enable CPU hotplug support + + "Processor type and Features" -> Support for Hotpluggable CPUs + +Make sure that you have CONFIG_HOTPLUG, and CONFIG_SMP turned on as well. + +You would need to enable CONFIG_HOTPLUG_CPU for SMP suspend/resume support +as well. + +Q: What architectures support CPU hotplug? +A: As of 2.6.14, the following architectures support CPU hotplug. + +i386 (Intel), ppc, ppc64, parisc, s390, ia64 and x86_64 + +Q: How to test if hotplug is supported on the newly built kernel? +A: You should now notice an entry in sysfs. + +Check if sysfs is mounted, using the "mount" command. You should notice +an entry as shown below in the output. + +.... +none on /sys type sysfs (rw) +.... + +if this is not mounted, do the following. + +#mkdir /sysfs +#mount -t sysfs sys /sys + +now you should see entries for all present cpu, the following is an example +in a 8-way system. + +#pwd +#/sys/devices/system/cpu +#ls -l +total 0 +drwxr-xr-x 10 root root 0 Sep 19 07:44 . +drwxr-xr-x 13 root root 0 Sep 19 07:45 .. +drwxr-xr-x 3 root root 0 Sep 19 07:44 cpu0 +drwxr-xr-x 3 root root 0 Sep 19 07:44 cpu1 +drwxr-xr-x 3 root root 0 Sep 19 07:44 cpu2 +drwxr-xr-x 3 root root 0 Sep 19 07:44 cpu3 +drwxr-xr-x 3 root root 0 Sep 19 07:44 cpu4 +drwxr-xr-x 3 root root 0 Sep 19 07:44 cpu5 +drwxr-xr-x 3 root root 0 Sep 19 07:44 cpu6 +drwxr-xr-x 3 root root 0 Sep 19 07:48 cpu7 + +Under each directory you would find an "online" file which is the control +file to logically online/offline a processor. + +Q: Does hot-add/hot-remove refer to physical add/remove of cpus? +A: The usage of hot-add/remove may not be very consistently used in the code. +CONFIG_CPU_HOTPLUG enables logical online/offline capability in the kernel. +To support physical addition/removal, one would need some BIOS hooks and +the platform should have something like an attention button in PCI hotplug. +CONFIG_ACPI_HOTPLUG_CPU enables ACPI support for physical add/remove of CPUs. + +Q: How do i logically offline a CPU? +A: Do the following. + +#echo 0 > /sys/devices/system/cpu/cpuX/online + +once the logical offline is successful, check + +#cat /proc/interrupts + +you should now not see the CPU that you removed. Also online file will report +the state as 0 when a cpu if offline and 1 when its online. + +#To display the current cpu state. +#cat /sys/devices/system/cpu/cpuX/online + +Q: Why cant i remove CPU0 on some systems? +A: Some architectures may have some special dependency on a certain CPU. + +For e.g in IA64 platforms we have ability to sent platform interrupts to the +OS. a.k.a Corrected Platform Error Interrupts (CPEI). In current ACPI +specifications, we didn't have a way to change the target CPU. Hence if the +current ACPI version doesn't support such re-direction, we disable that CPU +by making it not-removable. + +In such cases you will also notice that the online file is missing under cpu0. + +Q: How do i find out if a particular CPU is not removable? +A: Depending on the implementation, some architectures may show this by the +absence of the "online" file. This is done if it can be determined ahead of +time that this CPU cannot be removed. + +In some situations, this can be a run time check, i.e if you try to remove the +last CPU, this will not be permitted. You can find such failures by +investigating the return value of the "echo" command. + +Q: What happens when a CPU is being logically offlined? +A: The following happen, listed in no particular order :-) + +- A notification is sent to in-kernel registered modules by sending an event + CPU_DOWN_PREPARE +- All process is migrated away from this outgoing CPU to a new CPU +- All interrupts targeted to this CPU is migrated to a new CPU +- timers/bottom half/task lets are also migrated to a new CPU +- Once all services are migrated, kernel calls an arch specific routine + __cpu_disable() to perform arch specific cleanup. +- Once this is successful, an event for successful cleanup is sent by an event + CPU_DEAD. + + "It is expected that each service cleans up when the CPU_DOWN_PREPARE + notifier is called, when CPU_DEAD is called its expected there is nothing + running on behalf of this CPU that was offlined" + +Q: If i have some kernel code that needs to be aware of CPU arrival and + departure, how to i arrange for proper notification? +A: This is what you would need in your kernel code to receive notifications. + + #include <linux/cpu.h> + static int __cpuinit foobar_cpu_callback(struct notifier_block *nfb, + unsigned long action, void *hcpu) + { + unsigned int cpu = (unsigned long)hcpu; + + switch (action) { + case CPU_ONLINE: + foobar_online_action(cpu); + break; + case CPU_DEAD: + foobar_dead_action(cpu); + break; + } + return NOTIFY_OK; + } + + static struct notifier_block foobar_cpu_notifer = + { + .notifier_call = foobar_cpu_callback, + }; + + +In your init function, + + register_cpu_notifier(&foobar_cpu_notifier); + +You can fail PREPARE notifiers if something doesn't work to prepare resources. +This will stop the activity and send a following CANCELED event back. + +CPU_DEAD should not be failed, its just a goodness indication, but bad +things will happen if a notifier in path sent a BAD notify code. + +Q: I don't see my action being called for all CPUs already up and running? +A: Yes, CPU notifiers are called only when new CPUs are on-lined or offlined. + If you need to perform some action for each cpu already in the system, then + + for_each_online_cpu(i) { + foobar_cpu_callback(&foobar_cpu_notifier, CPU_UP_PREPARE, i); + foobar_cpu_callback(&foobar-cpu_notifier, CPU_ONLINE, i); + } + +Q: If i would like to develop cpu hotplug support for a new architecture, + what do i need at a minimum? +A: The following are what is required for CPU hotplug infrastructure to work + correctly. + + - Make sure you have an entry in Kconfig to enable CONFIG_HOTPLUG_CPU + - __cpu_up() - Arch interface to bring up a CPU + - __cpu_disable() - Arch interface to shutdown a CPU, no more interrupts + can be handled by the kernel after the routine + returns. Including local APIC timers etc are + shutdown. + - __cpu_die() - This actually supposed to ensure death of the CPU. + Actually look at some example code in other arch + that implement CPU hotplug. The processor is taken + down from the idle() loop for that specific + architecture. __cpu_die() typically waits for some + per_cpu state to be set, to ensure the processor + dead routine is called to be sure positively. + +Q: I need to ensure that a particular cpu is not removed when there is some + work specific to this cpu is in progress. +A: First switch the current thread context to preferred cpu + + int my_func_on_cpu(int cpu) + { + cpumask_t saved_mask, new_mask = CPU_MASK_NONE; + int curr_cpu, err = 0; + + saved_mask = current->cpus_allowed; + cpu_set(cpu, new_mask); + err = set_cpus_allowed(current, new_mask); + + if (err) + return err; + + /* + * If we got scheduled out just after the return from + * set_cpus_allowed() before running the work, this ensures + * we stay locked. + */ + curr_cpu = get_cpu(); + + if (curr_cpu != cpu) { + err = -EAGAIN; + goto ret; + } else { + /* + * Do work : But cant sleep, since get_cpu() disables preempt + */ + } + ret: + put_cpu(); + set_cpus_allowed(current, saved_mask); + return err; + } + + +Q: How do we determine how many CPUs are available for hotplug. +A: There is no clear spec defined way from ACPI that can give us that + information today. Based on some input from Natalie of Unisys, + that the ACPI MADT (Multiple APIC Description Tables) marks those possible + CPUs in a system with disabled status. + + Andi implemented some simple heuristics that count the number of disabled + CPUs in MADT as hotpluggable CPUS. In the case there are no disabled CPUS + we assume 1/2 the number of CPUs currently present can be hotplugged. + + Caveat: Today's ACPI MADT can only provide 256 entries since the apicid field + in MADT is only 8 bits. + +User Space Notification + +Hotplug support for devices is common in Linux today. Its being used today to +support automatic configuration of network, usb and pci devices. A hotplug +event can be used to invoke an agent script to perform the configuration task. + +You can add /etc/hotplug/cpu.agent to handle hotplug notification user space +scripts. + + #!/bin/bash + # $Id: cpu.agent + # Kernel hotplug params include: + #ACTION=%s [online or offline] + #DEVPATH=%s + # + cd /etc/hotplug + . ./hotplug.functions + + case $ACTION in + online) + echo `date` ":cpu.agent" add cpu >> /tmp/hotplug.txt + ;; + offline) + echo `date` ":cpu.agent" remove cpu >>/tmp/hotplug.txt + ;; + *) + debug_mesg CPU $ACTION event not supported + exit 1 + ;; + esac diff --git a/Documentation/cpusets.txt b/Documentation/cpusets.txt index a09a8eb80665ed..9e49b1c3572961 100644 --- a/Documentation/cpusets.txt +++ b/Documentation/cpusets.txt @@ -14,7 +14,10 @@ CONTENTS: 1.1 What are cpusets ? 1.2 Why are cpusets needed ? 1.3 How are cpusets implemented ? - 1.4 How do I use cpusets ? + 1.4 What are exclusive cpusets ? + 1.5 What does notify_on_release do ? + 1.6 What is memory_pressure ? + 1.7 How do I use cpusets ? 2. Usage Examples and Syntax 2.1 Basic Usage 2.2 Adding/removing cpus @@ -49,29 +52,6 @@ its cpus_allowed vector, and the kernel page allocator will not allocate a page on a node that is not allowed in the requesting tasks mems_allowed vector. -If a cpuset is cpu or mem exclusive, no other cpuset, other than a direct -ancestor or descendent, may share any of the same CPUs or Memory Nodes. -A cpuset that is cpu exclusive has a sched domain associated with it. -The sched domain consists of all cpus in the current cpuset that are not -part of any exclusive child cpusets. -This ensures that the scheduler load balacing code only balances -against the cpus that are in the sched domain as defined above and not -all of the cpus in the system. This removes any overhead due to -load balancing code trying to pull tasks outside of the cpu exclusive -cpuset only to be prevented by the tasks' cpus_allowed mask. - -A cpuset that is mem_exclusive restricts kernel allocations for -page, buffer and other data commonly shared by the kernel across -multiple users. All cpusets, whether mem_exclusive or not, restrict -allocations of memory for user space. This enables configuring a -system so that several independent jobs can share common kernel -data, such as file system pages, while isolating each jobs user -allocation in its own cpuset. To do this, construct a large -mem_exclusive cpuset to hold all the jobs, and construct child, -non-mem_exclusive cpusets for each individual job. Only a small -amount of typical kernel memory, such as requests from interrupt -handlers, is allowed to be taken outside even a mem_exclusive cpuset. - User level code may create and destroy cpusets by name in the cpuset virtual file system, manage the attributes and permissions of these cpusets and which CPUs and Memory Nodes are assigned to each cpuset, @@ -192,9 +172,15 @@ containing the following files describing that cpuset: - cpus: list of CPUs in that cpuset - mems: list of Memory Nodes in that cpuset + - memory_migrate flag: if set, move pages to cpusets nodes - cpu_exclusive flag: is cpu placement exclusive? - mem_exclusive flag: is memory placement exclusive? - tasks: list of tasks (by pid) attached to that cpuset + - notify_on_release flag: run /sbin/cpuset_release_agent on exit? + - memory_pressure: measure of how much paging pressure in cpuset + +In addition, the root cpuset only has the following file: + - memory_pressure_enabled flag: compute memory_pressure? New cpusets are created using the mkdir system call or shell command. The properties of a cpuset, such as its flags, allowed @@ -228,7 +214,108 @@ exclusive cpuset. Also, the use of a Linux virtual file system (vfs) to represent the cpuset hierarchy provides for a familiar permission and name space for cpusets, with a minimum of additional kernel code. -1.4 How do I use cpusets ? + +1.4 What are exclusive cpusets ? +-------------------------------- + +If a cpuset is cpu or mem exclusive, no other cpuset, other than +a direct ancestor or descendent, may share any of the same CPUs or +Memory Nodes. + +A cpuset that is cpu_exclusive has a scheduler (sched) domain +associated with it. The sched domain consists of all CPUs in the +current cpuset that are not part of any exclusive child cpusets. +This ensures that the scheduler load balancing code only balances +against the CPUs that are in the sched domain as defined above and +not all of the CPUs in the system. This removes any overhead due to +load balancing code trying to pull tasks outside of the cpu_exclusive +cpuset only to be prevented by the tasks' cpus_allowed mask. + +A cpuset that is mem_exclusive restricts kernel allocations for +page, buffer and other data commonly shared by the kernel across +multiple users. All cpusets, whether mem_exclusive or not, restrict +allocations of memory for user space. This enables configuring a +system so that several independent jobs can share common kernel data, +such as file system pages, while isolating each jobs user allocation in +its own cpuset. To do this, construct a large mem_exclusive cpuset to +hold all the jobs, and construct child, non-mem_exclusive cpusets for +each individual job. Only a small amount of typical kernel memory, +such as requests from interrupt handlers, is allowed to be taken +outside even a mem_exclusive cpuset. + + +1.5 What does notify_on_release do ? +------------------------------------ + +If the notify_on_release flag is enabled (1) in a cpuset, then whenever +the last task in the cpuset leaves (exits or attaches to some other +cpuset) and the last child cpuset of that cpuset is removed, then +the kernel runs the command /sbin/cpuset_release_agent, supplying the +pathname (relative to the mount point of the cpuset file system) of the +abandoned cpuset. This enables automatic removal of abandoned cpusets. +The default value of notify_on_release in the root cpuset at system +boot is disabled (0). The default value of other cpusets at creation +is the current value of their parents notify_on_release setting. + + +1.6 What is memory_pressure ? +----------------------------- +The memory_pressure of a cpuset provides a simple per-cpuset metric +of the rate that the tasks in a cpuset are attempting to free up in +use memory on the nodes of the cpuset to satisfy additional memory +requests. + +This enables batch managers monitoring jobs running in dedicated +cpusets to efficiently detect what level of memory pressure that job +is causing. + +This is useful both on tightly managed systems running a wide mix of +submitted jobs, which may choose to terminate or re-prioritize jobs that +are trying to use more memory than allowed on the nodes assigned them, +and with tightly coupled, long running, massively parallel scientific +computing jobs that will dramatically fail to meet required performance +goals if they start to use more memory than allowed to them. + +This mechanism provides a very economical way for the batch manager +to monitor a cpuset for signs of memory pressure. It's up to the +batch manager or other user code to decide what to do about it and +take action. + +==> Unless this feature is enabled by writing "1" to the special file + /dev/cpuset/memory_pressure_enabled, the hook in the rebalance + code of __alloc_pages() for this metric reduces to simply noticing + that the cpuset_memory_pressure_enabled flag is zero. So only + systems that enable this feature will compute the metric. + +Why a per-cpuset, running average: + + Because this meter is per-cpuset, rather than per-task or mm, + the system load imposed by a batch scheduler monitoring this + metric is sharply reduced on large systems, because a scan of + the tasklist can be avoided on each set of queries. + + Because this meter is a running average, instead of an accumulating + counter, a batch scheduler can detect memory pressure with a + single read, instead of having to read and accumulate results + for a period of time. + + Because this meter is per-cpuset rather than per-task or mm, + the batch scheduler can obtain the key information, memory + pressure in a cpuset, with a single read, rather than having to + query and accumulate results over all the (dynamically changing) + set of tasks in the cpuset. + +A per-cpuset simple digital filter (requires a spinlock and 3 words +of data per-cpuset) is kept, and updated by any task attached to that +cpuset, if it enters the synchronous (direct) page reclaim code. + +A per-cpuset file provides an integer number representing the recent +(half-life of 10 seconds) rate of direct page reclaims caused by +the tasks in the cpuset, in units of reclaims attempted per second, +times 1000. + + +1.7 How do I use cpusets ? -------------------------- In order to minimize the impact of cpusets on critical kernel @@ -277,6 +364,30 @@ rewritten to the 'tasks' file of its cpuset. This is done to avoid impacting the scheduler code in the kernel with a check for changes in a tasks processor placement. +Normally, once a page is allocated (given a physical page +of main memory) then that page stays on whatever node it +was allocated, so long as it remains allocated, even if the +cpusets memory placement policy 'mems' subsequently changes. +If the cpuset flag file 'memory_migrate' is set true, then when +tasks are attached to that cpuset, any pages that task had +allocated to it on nodes in its previous cpuset are migrated +to the tasks new cpuset. Depending on the implementation, +this migration may either be done by swapping the page out, +so that the next time the page is referenced, it will be paged +into the tasks new cpuset, usually on the node where it was +referenced, or this migration may be done by directly copying +the pages from the tasks previous cpuset to the new cpuset, +where possible to the same node, relative to the new cpuset, +as the node that held the page, relative to the old cpuset. +Also if 'memory_migrate' is set true, then if that cpusets +'mems' file is modified, pages allocated to tasks in that +cpuset, that were on nodes in the previous setting of 'mems', +will be moved to nodes in the new setting of 'mems.' Again, +depending on the implementation, this might be done by swapping, +or by direct copying. In either case, pages that were not in +the tasks prior cpuset, or in the cpusets prior 'mems' setting, +will not be moved. + There is an exception to the above. If hotplug functionality is used to remove all the CPUs that are currently assigned to a cpuset, then the kernel will automatically update the cpus_allowed of all diff --git a/Documentation/dvb/avermedia.txt b/Documentation/dvb/avermedia.txt index 2dc260b2b0a4a4..068070ff13cd0a 100644 --- a/Documentation/dvb/avermedia.txt +++ b/Documentation/dvb/avermedia.txt @@ -150,7 +150,8 @@ Getting the card going The frontend module sp887x.o, requires an external firmware. Please use the command "get_dvb_firmware sp887x" to download - it. Then copy it to /usr/lib/hotplug/firmware. + it. Then copy it to /usr/lib/hotplug/firmware or /lib/firmware/ + (depending on configuration of firmware hotplug). Receiving DVB-T in Australia diff --git a/Documentation/dvb/get_dvb_firmware b/Documentation/dvb/get_dvb_firmware index be6eb4c759915f..75c28a174092f5 100644 --- a/Documentation/dvb/get_dvb_firmware +++ b/Documentation/dvb/get_dvb_firmware @@ -23,7 +23,7 @@ use IO::Handle; @components = ( "sp8870", "sp887x", "tda10045", "tda10046", "av7110", "dec2000t", "dec2540t", "dec3000s", "vp7041", "dibusb", "nxt2002", "nxt2004", - "or51211", "or51132_qam", "or51132_vsb"); + "or51211", "or51132_qam", "or51132_vsb", "bluebird"); # Check args syntax() if (scalar(@ARGV) != 1); @@ -34,7 +34,11 @@ for ($i=0; $i < scalar(@components); $i++) { if ($cid eq $components[$i]) { $outfile = eval($cid); die $@ if $@; - print STDERR "Firmware $outfile extracted successfully. Now copy it to either /lib/firmware or /usr/lib/hotplug/firmware/ (depending on your hotplug version).\n"; + print STDERR <<EOF; +Firmware $outfile extracted successfully. +Now copy it to either /usr/lib/hotplug/firmware or /lib/firmware +(depending on configuration of firmware hotplug). +EOF exit(0); } } @@ -243,7 +247,7 @@ sub nxt2002 { my $tmpdir = tempdir(DIR => "/tmp", CLEANUP => 1); checkstandard(); - + wgetfile($sourcefile, $url); unzip($sourcefile, $tmpdir); verify("$tmpdir/SkyNETU.sys", $hash); @@ -308,6 +312,19 @@ sub or51132_vsb { $fwfile; } +sub bluebird { + my $url = "http://www.linuxtv.org/download/dvb/firmware/dvb-usb-bluebird-01.fw"; + my $outfile = "dvb-usb-bluebird-01.fw"; + my $hash = "658397cb9eba9101af9031302671f49d"; + + checkstandard(); + + wgetfile($outfile, $url); + verify($outfile,$hash); + + $outfile; +} + # --------------------------------------------------------------- # Utilities diff --git a/Documentation/dvb/ttusb-dec.txt b/Documentation/dvb/ttusb-dec.txt index 5c1e984c26a768..b2f271cd784bc5 100644 --- a/Documentation/dvb/ttusb-dec.txt +++ b/Documentation/dvb/ttusb-dec.txt @@ -41,4 +41,5 @@ Hotplug Firmware Loading for 2.6 kernels For 2.6 kernels the firmware is loaded at the point that the driver module is loaded. See linux/Documentation/dvb/firmware.txt for more information. -Copy the three files downloaded above into the /usr/lib/hotplug/firmware directory. +Copy the three files downloaded above into the /usr/lib/hotplug/firmware or +/lib/firmware directory (depending on configuration of firmware hotplug). diff --git a/Documentation/fb/cyblafb/bugs b/Documentation/fb/cyblafb/bugs index f90cc66ea91972..9443a6d72cdd2a 100644 --- a/Documentation/fb/cyblafb/bugs +++ b/Documentation/fb/cyblafb/bugs @@ -11,4 +11,3 @@ Untested features All LCD stuff is untested. If it worked in tridentfb, it should work in cyblafb. Please test and report the results to Knut_Petersen@t-online.de. - diff --git a/Documentation/fb/cyblafb/fb.modes b/Documentation/fb/cyblafb/fb.modes index cf4351fc32ff69..fe0e5223ba86cd 100644 --- a/Documentation/fb/cyblafb/fb.modes +++ b/Documentation/fb/cyblafb/fb.modes @@ -14,142 +14,141 @@ # mode "640x480-50" - geometry 640 480 640 3756 8 + geometry 640 480 2048 4096 8 timings 47619 4294967256 24 17 0 216 3 endmode mode "640x480-60" - geometry 640 480 640 3756 8 + geometry 640 480 2048 4096 8 timings 39682 4294967256 24 17 0 216 3 endmode mode "640x480-70" - geometry 640 480 640 3756 8 + geometry 640 480 2048 4096 8 timings 34013 4294967256 24 17 0 216 3 endmode mode "640x480-72" - geometry 640 480 640 3756 8 + geometry 640 480 2048 4096 8 timings 33068 4294967256 24 17 0 216 3 endmode mode "640x480-75" - geometry 640 480 640 3756 8 + geometry 640 480 2048 4096 8 timings 31746 4294967256 24 17 0 216 3 endmode mode "640x480-80" - geometry 640 480 640 3756 8 + geometry 640 480 2048 4096 8 timings 29761 4294967256 24 17 0 216 3 endmode mode "640x480-85" - geometry 640 480 640 3756 8 + geometry 640 480 2048 4096 8 timings 28011 4294967256 24 17 0 216 3 endmode mode "800x600-50" - geometry 800 600 800 3221 8 + geometry 800 600 2048 4096 8 timings 30303 96 24 14 0 136 11 endmode mode "800x600-60" - geometry 800 600 800 3221 8 + geometry 800 600 2048 4096 8 timings 25252 96 24 14 0 136 11 endmode mode "800x600-70" - geometry 800 600 800 3221 8 + geometry 800 600 2048 4096 8 timings 21645 96 24 14 0 136 11 endmode mode "800x600-72" - geometry 800 600 800 3221 8 + geometry 800 600 2048 4096 8 timings 21043 96 24 14 0 136 11 endmode mode "800x600-75" - geometry 800 600 800 3221 8 + geometry 800 600 2048 4096 8 timings 20202 96 24 14 0 136 11 endmode mode "800x600-80" - geometry 800 600 800 3221 8 + geometry 800 600 2048 4096 8 timings 18939 96 24 14 0 136 11 endmode mode "800x600-85" - geometry 800 600 800 3221 8 + geometry 800 600 2048 4096 8 timings 17825 96 24 14 0 136 11 endmode mode "1024x768-50" - geometry 1024 768 1024 2815 8 + geometry 1024 768 2048 4096 8 timings 19054 144 24 29 0 120 3 endmode mode "1024x768-60" - geometry 1024 768 1024 2815 8 + geometry 1024 768 2048 4096 8 timings 15880 144 24 29 0 120 3 endmode mode "1024x768-70" - geometry 1024 768 1024 2815 8 + geometry 1024 768 2048 4096 8 timings 13610 144 24 29 0 120 3 endmode mode "1024x768-72" - geometry 1024 768 1024 2815 8 + geometry 1024 768 2048 4096 8 timings 13232 144 24 29 0 120 3 endmode mode "1024x768-75" - geometry 1024 768 1024 2815 8 + geometry 1024 768 2048 4096 8 timings 12703 144 24 29 0 120 3 endmode mode "1024x768-80" - geometry 1024 768 1024 2815 8 + geometry 1024 768 2048 4096 8 timings 11910 144 24 29 0 120 3 endmode mode "1024x768-85" - geometry 1024 768 1024 2815 8 + geometry 1024 768 2048 4096 8 timings 11209 144 24 29 0 120 3 endmode mode "1280x1024-50" - geometry 1280 1024 1280 2662 8 + geometry 1280 1024 2048 4096 8 timings 11114 232 16 39 0 160 3 endmode mode "1280x1024-60" - geometry 1280 1024 1280 2662 8 + geometry 1280 1024 2048 4096 8 timings 9262 232 16 39 0 160 3 endmode mode "1280x1024-70" - geometry 1280 1024 1280 2662 8 + geometry 1280 1024 2048 4096 8 timings 7939 232 16 39 0 160 3 endmode mode "1280x1024-72" - geometry 1280 1024 1280 2662 8 + geometry 1280 1024 2048 4096 8 timings 7719 232 16 39 0 160 3 endmode mode "1280x1024-75" - geometry 1280 1024 1280 2662 8 + geometry 1280 1024 2048 4096 8 timings 7410 232 16 39 0 160 3 endmode mode "1280x1024-80" - geometry 1280 1024 1280 2662 8 + geometry 1280 1024 2048 4096 8 timings 6946 232 16 39 0 160 3 endmode mode "1280x1024-85" - geometry 1280 1024 1280 2662 8 + geometry 1280 1024 2048 4096 8 timings 6538 232 16 39 0 160 3 endmode - diff --git a/Documentation/fb/cyblafb/performance b/Documentation/fb/cyblafb/performance index eb4e47a9cea62b..8d15d5dfc6b34a 100644 --- a/Documentation/fb/cyblafb/performance +++ b/Documentation/fb/cyblafb/performance @@ -77,4 +77,3 @@ patch that speeds up kernel bitblitting a lot ( > 20%). | | | | | | | | | | +-----------+-----------------+-----------------+-----------------+ - diff --git a/Documentation/fb/cyblafb/todo b/Documentation/fb/cyblafb/todo index 80fb2f89b6c173..c5f6d0eae54531 100644 --- a/Documentation/fb/cyblafb/todo +++ b/Documentation/fb/cyblafb/todo @@ -22,11 +22,10 @@ accelerated color blitting Who needs it? The console driver does use color everything else is done using color expanding blitting of 1bpp character bitmaps. -xpanning Who needs it? - ioctls Who needs it? -TV-out Will be done later +TV-out Will be done later. Use "vga= " at boot time + to set a suitable video mode. ??? Feel free to contact me if you have any feature requests diff --git a/Documentation/fb/cyblafb/usage b/Documentation/fb/cyblafb/usage index e627c8f542115c..a39bb3d402a2b0 100644 --- a/Documentation/fb/cyblafb/usage +++ b/Documentation/fb/cyblafb/usage @@ -40,6 +40,16 @@ Selecting Modes None of the modes possible to select as startup modes are affected by the problems described at the end of the next subsection. + For all startup modes cyblafb chooses a virtual x resolution of 2048, + the only exception is mode 1280x1024 in combination with 32 bpp. This + allows ywrap scrolling for all those modes if rotation is 0 or 2, and + also fast scrolling if rotation is 1 or 3. The default virtual y reso- + lution is 4096 for bpp == 8, 2048 for bpp==16 and 1024 for bpp == 32, + again with the only exception of 1280x1024 at 32 bpp. + + Please do set your video memory size to 8 Mb in the Bios setup. Other + values will work, but performace is decreased for a lot of modes. + Mode changes using fbset ======================== @@ -54,20 +64,26 @@ Selecting Modes - if a flat panel is found, cyblafb does not allow you to program a resolution higher than the physical resolution of the flat panel monitor - - cyblafb does not allow xres to differ from xres_virtual - cyblafb does not allow vclk to exceed 230 MHz. As 32 bpp and (currently) 24 bit modes use a doubled vclk internally, the dotclock limit as seen by fbset is 115 MHz for those modes and 230 MHz for 8 and 16 bpp modes. + - cyblafb will allow you to select very high resolutions as + long as the hardware can be programmed to these modes. The + documented limit 1600x1200 is not enforced, but don't expect + perfect signal quality. - Any request that violates the rules given above will be ignored and - fbset will return an error. + Any request that violates the rules given above will be either changed + to something the hardware supports or an error value will be returned. If you program a virtual y resolution higher than the hardware limit, cyblafb will silently decrease that value to the highest possible - value. + value. The same is true for a virtual x resolution that is not + supported by the hardware. Cyblafb tries to adapt vyres first because + vxres decides if ywrap scrolling is possible or not. - Attempts to disable acceleration are ignored. + Attempts to disable acceleration are ignored, I believe that this is + safe. Some video modes that should work do not work as expected. If you use the standard fb.modes, fbset 640x480-60 will program that mode, but @@ -129,10 +145,6 @@ mode 640x480 or 800x600 or 1024x768 or 1280x1024 verbosity 0 is the default, increase to at least 2 for every bug report! -vesafb allows cyblafb to be loaded after vesafb has been - loaded. See sections "Module unloading ...". - - Development hints ================= @@ -195,7 +207,7 @@ a graphics mode. After booting, load cyblafb without any mode and bpp parameter and assign cyblafb to individual ttys using con2fb, e.g.: - modprobe cyblafb vesafb=1 + modprobe cyblafb con2fb /dev/fb1 /dev/tty1 Unloading cyblafb works without problems after you assign vesafb to all @@ -203,4 +215,3 @@ ttys again, e.g.: con2fb /dev/fb0 /dev/tty1 rmmod cyblafb - diff --git a/Documentation/fb/cyblafb/whatsnew b/Documentation/fb/cyblafb/whatsnew new file mode 100644 index 00000000000000..76c07a26e04436 --- /dev/null +++ b/Documentation/fb/cyblafb/whatsnew @@ -0,0 +1,29 @@ +0.62 +==== + + - the vesafb parameter has been removed as I decided to allow the + feature without any special parameter. + + - Cyblafb does not use the vga style of panning any longer, now the + "right view" register in the graphics engine IO space is used. Without + that change it was impossible to use all available memory, and without + access to all available memory it is impossible to ywrap. + + - The imageblit function now uses hardware acceleration for all font + widths. Hardware blitting across pixel column 2048 is broken in the + cyberblade/i1 graphics core, but we work around that hardware bug. + + - modes with vxres != xres are supported now. + + - ywrap scrolling is supported now and the default. This is a big + performance gain. + + - default video modes use vyres > yres and vxres > xres to allow + almost optimal scrolling speed for normal and rotated screens + + - some features mainly usefull for debugging the upper layers of the + framebuffer system have been added, have a look at the code + + - fixed: Oops after unloading cyblafb when reading /proc/io* + + - we work around some bugs of the higher framebuffer layers. diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 8ae8dad8e15048..9474501dd6cc4d 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -71,15 +71,6 @@ Who: Mauro Carvalho Chehab <mchehab@brturbo.com.br> --------------------------- -What: i2c sysfs name change: in1_ref, vid deprecated in favour of cpu0_vid -When: November 2005 -Files: drivers/i2c/chips/adm1025.c, drivers/i2c/chips/adm1026.c -Why: Match the other drivers' name for the same function, duplicate names - will be available until removal of old names. -Who: Grant Coady <gcoady@gmail.com> - ---------------------------- - What: remove EXPORT_SYMBOL(panic_timeout) When: April 2006 Files: kernel/panic.c diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt index 9840d5b8d5b999..f4d0de6bac6363 100644 --- a/Documentation/filesystems/ext3.txt +++ b/Documentation/filesystems/ext3.txt @@ -2,11 +2,11 @@ Ext3 Filesystem =============== -ext3 was originally released in September 1999. Written by Stephen Tweedie -for 2.2 branch, and ported to 2.4 kernels by Peter Braam, Andreas Dilger, +Ext3 was originally released in September 1999. Written by Stephen Tweedie +for the 2.2 branch, and ported to 2.4 kernels by Peter Braam, Andreas Dilger, Andrew Morton, Alexander Viro, Ted Ts'o and Stephen Tweedie. -ext3 is ext2 filesystem enhanced with journalling capabilities. +Ext3 is the ext2 filesystem enhanced with journalling capabilities. Options ======= @@ -14,64 +14,71 @@ Options When mounting an ext3 filesystem, the following option are accepted: (*) == default -jounal=update Update the ext3 file system's journal to the - current format. +journal=update Update the ext3 file system's journal to the current + format. -journal=inum When a journal already exists, this option is - ignored. Otherwise, it specifies the number of - the inode which will represent the ext3 file - system's journal file. +journal=inum When a journal already exists, this option is ignored. + Otherwise, it specifies the number of the inode which + will represent the ext3 file system's journal file. + +journal_dev=devnum When the external journal device's major/minor numbers + have changed, this option allows the user to specify + the new journal location. The journal device is + identified through its new major/minor numbers encoded + in devnum. noload Don't load the journal on mounting. -data=journal All data are committed into the journal prior - to being written into the main file system. +data=journal All data are committed into the journal prior to being + written into the main file system. data=ordered (*) All data are forced directly out to the main file - system prior to its metadata being committed to - the journal. + system prior to its metadata being committed to the + journal. -data=writeback Data ordering is not preserved, data may be - written into the main file system after its - metadata has been committed to the journal. +data=writeback Data ordering is not preserved, data may be written + into the main file system after its metadata has been + committed to the journal. commit=nrsec (*) Ext3 can be told to sync all its data and metadata every 'nrsec' seconds. The default value is 5 seconds. - This means that if you lose your power, you will lose, - as much, the latest 5 seconds of work (your filesystem - will not be damaged though, thanks to journaling). This - default value (or any low value) will hurt performance, - but it's good for data-safety. Setting it to 0 will - have the same effect than leaving the default 5 sec. + This means that if you lose your power, you will lose + as much as the latest 5 seconds of work (your + filesystem will not be damaged though, thanks to the + journaling). This default value (or any low value) + will hurt performance, but it's good for data-safety. + Setting it to 0 will have the same effect as leaving + it at the default (5 seconds). Setting it to very large values will improve performance. -barrier=1 This enables/disables barriers. barrier=0 disables it, - barrier=1 enables it. +barrier=1 This enables/disables barriers. barrier=0 disables + it, barrier=1 enables it. -orlov (*) This enables the new Orlov block allocator. It's enabled - by default. +orlov (*) This enables the new Orlov block allocator. It is + enabled by default. -oldalloc This disables the Orlov block allocator and enables the - old block allocator. Orlov should have better performance, - we'd like to get some feedback if it's the contrary for - you. +oldalloc This disables the Orlov block allocator and enables + the old block allocator. Orlov should have better + performance - we'd like to get some feedback if it's + the contrary for you. -user_xattr Enables Extended User Attributes. Additionally, you need - to have extended attribute support enabled in the kernel - configuration (CONFIG_EXT3_FS_XATTR). See the attr(5) - manual page and http://acl.bestbits.at to learn more - about extended attributes. +user_xattr Enables Extended User Attributes. Additionally, you + need to have extended attribute support enabled in the + kernel configuration (CONFIG_EXT3_FS_XATTR). See the + attr(5) manual page and http://acl.bestbits.at/ to + learn more about extended attributes. nouser_xattr Disables Extended User Attributes. -acl Enables POSIX Access Control Lists support. Additionally, - you need to have ACL support enabled in the kernel - configuration (CONFIG_EXT3_FS_POSIX_ACL). See the acl(5) - manual page and http://acl.bestbits.at for more - information. +acl Enables POSIX Access Control Lists support. + Additionally, you need to have ACL support enabled in + the kernel configuration (CONFIG_EXT3_FS_POSIX_ACL). + See the acl(5) manual page and http://acl.bestbits.at/ + for more information. -noacl This option disables POSIX Access Control List support. +noacl This option disables POSIX Access Control List + support. reservation @@ -83,7 +90,7 @@ bsddf (*) Make 'df' act like BSD. minixdf Make 'df' act like Minix. check=none Don't do extra checking of bitmaps on mount. -nocheck +nocheck debug Extra debugging information is sent to syslog. @@ -92,7 +99,7 @@ errors=continue Keep going on a filesystem error. errors=panic Panic and halt the machine if an error occurs. grpid Give objects the same group ID as their creator. -bsdgroups +bsdgroups nogrpid (*) New objects have the group ID of their creator. sysvgroups @@ -103,81 +110,81 @@ resuid=n The user ID which may use the reserved blocks. sb=n Use alternate superblock at this location. -quota Quota options are currently silently ignored. -noquota (see fs/ext3/super.c, line 594) +quota +noquota grpquota usrquota Specification ============= -ext3 shares all disk implementation with ext2 filesystem, and add -transactions capabilities to ext2. Journaling is done by the -Journaling block device layer. +Ext3 shares all disk implementation with the ext2 filesystem, and adds +transactions capabilities to ext2. Journaling is done by the Journaling Block +Device layer. Journaling Block Device layer ----------------------------- -The Journaling Block Device layer (JBD) isn't ext3 specific. It was -design to add journaling capabilities on a block device. The ext3 -filesystem code will inform the JBD of modifications it is performing -(Call a transaction). the journal support the transactions start and -stop, and in case of crash, the journal can replayed the transactions -to put the partition on a consistent state fastly. +The Journaling Block Device layer (JBD) isn't ext3 specific. It was design to +add journaling capabilities on a block device. The ext3 filesystem code will +inform the JBD of modifications it is performing (called a transaction). The +journal supports the transactions start and stop, and in case of crash, the +journal can replayed the transactions to put the partition back in a +consistent state fast. -handles represent a single atomic update to a filesystem. JBD can -handle external journal on a block device. +Handles represent a single atomic update to a filesystem. JBD can handle an +external journal on a block device. Data Mode --------- -There's 3 different data modes: +There are 3 different data modes: * writeback mode -In data=writeback mode, ext3 does not journal data at all. This mode -provides a similar level of journaling as XFS, JFS, and ReiserFS in its -default mode - metadata journaling. A crash+recovery can cause -incorrect data to appear in files which were written shortly before the -crash. This mode will typically provide the best ext3 performance. +In data=writeback mode, ext3 does not journal data at all. This mode provides +a similar level of journaling as that of XFS, JFS, and ReiserFS in its default +mode - metadata journaling. A crash+recovery can cause incorrect data to +appear in files which were written shortly before the crash. This mode will +typically provide the best ext3 performance. * ordered mode -In data=ordered mode, ext3 only officially journals metadata, but it -logically groups metadata and data blocks into a single unit called a -transaction. When it's time to write the new metadata out to disk, the -associated data blocks are written first. In general, this mode -perform slightly slower than writeback but significantly faster than -journal mode. +In data=ordered mode, ext3 only officially journals metadata, but it logically +groups metadata and data blocks into a single unit called a transaction. When +it's time to write the new metadata out to disk, the associated data blocks +are written first. In general, this mode performs slightly slower than +writeback but significantly faster than journal mode. * journal mode -data=journal mode provides full data and metadata journaling. All new -data is written to the journal first, and then to its final location. -In the event of a crash, the journal can be replayed, bringing both -data and metadata into a consistent state. This mode is the slowest -except when data needs to be read from and written to disk at the same -time where it outperform all others mode. +data=journal mode provides full data and metadata journaling. All new data is +written to the journal first, and then to its final location. +In the event of a crash, the journal can be replayed, bringing both data and +metadata into a consistent state. This mode is the slowest except when data +needs to be read from and written to disk at the same time where it +outperforms all others modes. Compatibility ------------- Ext2 partitions can be easily convert to ext3, with `tune2fs -j <dev>`. -Ext3 is fully compatible with Ext2. Ext3 partitions can easily be -mounted as Ext2. +Ext3 is fully compatible with Ext2. Ext3 partitions can easily be mounted as +Ext2. + External Tools ============== -see manual pages to know more. +See manual pages to learn more. + +tune2fs: create a ext3 journal on a ext2 partition with the -j flag. +mke2fs: create a ext3 partition with the -j flag. +debugfs: ext2 and ext3 file system debugger. -tune2fs: create a ext3 journal on a ext2 partition with the -j flags -mke2fs: create a ext3 partition with the -j flags -debugfs: ext2 and ext3 file system debugger References ========== -kernel source: file:/usr/src/linux/fs/ext3 - file:/usr/src/linux/fs/jbd +kernel source: <file:fs/ext3/> + <file:fs/jbd/> -programs: http://e2fsprogs.sourceforge.net +programs: http://e2fsprogs.sourceforge.net/ -useful link: - http://www.zip.com.au/~akpm/linux/ext3/ext3-usage.html +useful links: http://www.zip.com.au/~akpm/linux/ext3/ext3-usage.html http://www-106.ibm.com/developerworks/linux/library/l-fs7/ http://www-106.ibm.com/developerworks/linux/library/l-fs8/ diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index d4773565ea2f20..944cf109a6f5a3 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -418,7 +418,7 @@ VmallocChunk: 111088 kB Dirty: Memory which is waiting to get written back to the disk Writeback: Memory which is actively being written back to the disk Mapped: files which have been mmaped, such as libraries - Slab: in-kernel data structures cache + Slab: in-kernel data structures cache CommitLimit: Based on the overcommit ratio ('vm.overcommit_ratio'), this is the total amount of memory currently available to be allocated on the system. This limit is only adhered to @@ -1302,6 +1302,23 @@ VM has token based thrashing control mechanism and uses the token to prevent unnecessary page faults in thrashing situation. The unit of the value is second. The value would be useful to tune thrashing behavior. +drop_caches +----------- + +Writing to this will cause the kernel to drop clean caches, dentries and +inodes from memory, causing that memory to become free. + +To free pagecache: + echo 1 > /proc/sys/vm/drop_caches +To free dentries and inodes: + echo 2 > /proc/sys/vm/drop_caches +To free pagecache, dentries and inodes: + echo 3 > /proc/sys/vm/drop_caches + +As this is a non-destructive operation and dirty objects are not freeable, the +user should run `sync' first. + + 2.5 /proc/sys/dev - Device specific parameters ---------------------------------------------- diff --git a/Documentation/filesystems/ramfs-rootfs-initramfs.txt b/Documentation/filesystems/ramfs-rootfs-initramfs.txt index b3404a0325967d..60ab61e54e8ab9 100644 --- a/Documentation/filesystems/ramfs-rootfs-initramfs.txt +++ b/Documentation/filesystems/ramfs-rootfs-initramfs.txt @@ -143,12 +143,26 @@ as the following example: dir /mnt 755 0 0 file /init initramfs/init.sh 755 0 0 +Run "usr/gen_init_cpio" (after the kernel build) to get a usage message +documenting the above file format. + One advantage of the text file is that root access is not required to set permissions or create device nodes in the new archive. (Note that those two example "file" entries expect to find files named "init.sh" and "busybox" in a directory called "initramfs", under the linux-2.6.* directory. See Documentation/early-userspace/README for more details.) +The kernel does not depend on external cpio tools, gen_init_cpio is created +from usr/gen_init_cpio.c which is entirely self-contained, and the kernel's +boot-time extractor is also (obviously) self-contained. However, if you _do_ +happen to have cpio installed, the following command line can extract the +generated cpio image back into its component files: + + cpio -i -d -H newc -F initramfs_data.cpio --no-absolute-filenames + +Contents of initramfs: +---------------------- + If you don't already understand what shared libraries, devices, and paths you need to get a minimal root filesystem up and running, here are some references: @@ -161,13 +175,69 @@ designed to be a tiny C library to statically link early userspace code against, along with some related utilities. It is BSD licensed. I use uClibc (http://www.uclibc.org) and busybox (http://www.busybox.net) -myself. These are LGPL and GPL, respectively. +myself. These are LGPL and GPL, respectively. (A self-contained initramfs +package is planned for the busybox 1.2 release.) In theory you could use glibc, but that's not well suited for small embedded uses like this. (A "hello world" program statically linked against glibc is over 400k. With uClibc it's 7k. Also note that glibc dlopens libnss to do name lookups, even when otherwise statically linked.) +Why cpio rather than tar? +------------------------- + +This decision was made back in December, 2001. The discussion started here: + + http://www.uwsg.iu.edu/hypermail/linux/kernel/0112.2/1538.html + +And spawned a second thread (specifically on tar vs cpio), starting here: + + http://www.uwsg.iu.edu/hypermail/linux/kernel/0112.2/1587.html + +The quick and dirty summary version (which is no substitute for reading +the above threads) is: + +1) cpio is a standard. It's decades old (from the AT&T days), and already + widely used on Linux (inside RPM, Red Hat's device driver disks). Here's + a Linux Journal article about it from 1996: + + http://www.linuxjournal.com/article/1213 + + It's not as popular as tar because the traditional cpio command line tools + require _truly_hideous_ command line arguments. But that says nothing + either way about the archive format, and there are alternative tools, + such as: + + http://freshmeat.net/projects/afio/ + +2) The cpio archive format chosen by the kernel is simpler and cleaner (and + thus easier to create and parse) than any of the (literally dozens of) + various tar archive formats. The complete initramfs archive format is + explained in buffer-format.txt, created in usr/gen_init_cpio.c, and + extracted in init/initramfs.c. All three together come to less than 26k + total of human-readable text. + +3) The GNU project standardizing on tar is approximately as relevant as + Windows standardizing on zip. Linux is not part of either, and is free + to make its own technical decisions. + +4) Since this is a kernel internal format, it could easily have been + something brand new. The kernel provides its own tools to create and + extract this format anyway. Using an existing standard was preferable, + but not essential. + +5) Al Viro made the decision (quote: "tar is ugly as hell and not going to be + supported on the kernel side"): + + http://www.uwsg.iu.edu/hypermail/linux/kernel/0112.2/1540.html + + explained his reasoning: + + http://www.uwsg.iu.edu/hypermail/linux/kernel/0112.2/1550.html + http://www.uwsg.iu.edu/hypermail/linux/kernel/0112.2/1638.html + + and, most importantly, designed and implemented the initramfs code. + Future directions: ------------------ diff --git a/Documentation/filesystems/relayfs.txt b/Documentation/filesystems/relayfs.txt index d803abed29f01d..5832377b7340ed 100644 --- a/Documentation/filesystems/relayfs.txt +++ b/Documentation/filesystems/relayfs.txt @@ -44,30 +44,41 @@ relayfs can operate in a mode where it will overwrite data not yet collected by userspace, and not wait for it to consume it. relayfs itself does not provide for communication of such data between -userspace and kernel, allowing the kernel side to remain simple and not -impose a single interface on userspace. It does provide a separate -helper though, described below. +userspace and kernel, allowing the kernel side to remain simple and +not impose a single interface on userspace. It does provide a set of +examples and a separate helper though, described below. + +klog and relay-apps example code +================================ + +relayfs itself is ready to use, but to make things easier, a couple +simple utility functions and a set of examples are provided. + +The relay-apps example tarball, available on the relayfs sourceforge +site, contains a set of self-contained examples, each consisting of a +pair of .c files containing boilerplate code for each of the user and +kernel sides of a relayfs application; combined these two sets of +boilerplate code provide glue to easily stream data to disk, without +having to bother with mundane housekeeping chores. + +The 'klog debugging functions' patch (klog.patch in the relay-apps +tarball) provides a couple of high-level logging functions to the +kernel which allow writing formatted text or raw data to a channel, +regardless of whether a channel to write into exists or not, or +whether relayfs is compiled into the kernel or is configured as a +module. These functions allow you to put unconditional 'trace' +statements anywhere in the kernel or kernel modules; only when there +is a 'klog handler' registered will data actually be logged (see the +klog and kleak examples for details). + +It is of course possible to use relayfs from scratch i.e. without +using any of the relay-apps example code or klog, but you'll have to +implement communication between userspace and kernel, allowing both to +convey the state of buffers (full, empty, amount of padding). + +klog and the relay-apps examples can be found in the relay-apps +tarball on http://relayfs.sourceforge.net -klog, relay-app & librelay -========================== - -relayfs itself is ready to use, but to make things easier, two -additional systems are provided. klog is a simple wrapper to make -writing formatted text or raw data to a channel simpler, regardless of -whether a channel to write into exists or not, or whether relayfs is -compiled into the kernel or is configured as a module. relay-app is -the kernel counterpart of userspace librelay.c, combined these two -files provide glue to easily stream data to disk, without having to -bother with housekeeping. klog and relay-app can be used together, -with klog providing high-level logging functions to the kernel and -relay-app taking care of kernel-user control and disk-logging chores. - -It is possible to use relayfs without relay-app & librelay, but you'll -have to implement communication between userspace and kernel, allowing -both to convey the state of buffers (full, empty, amount of padding). - -klog, relay-app and librelay can be found in the relay-apps tarball on -http://relayfs.sourceforge.net The relayfs user space API ========================== @@ -125,6 +136,8 @@ Here's a summary of the API relayfs provides to in-kernel clients: relay_reset(chan) relayfs_create_dir(name, parent) relayfs_remove_dir(dentry) + relayfs_create_file(name, parent, mode, fops, data) + relayfs_remove_file(dentry) channel management typically called on instigation of userspace: @@ -141,6 +154,8 @@ Here's a summary of the API relayfs provides to in-kernel clients: subbuf_start(buf, subbuf, prev_subbuf, prev_padding) buf_mapped(buf, filp) buf_unmapped(buf, filp) + create_buf_file(filename, parent, mode, buf, is_global) + remove_buf_file(dentry) helper functions: @@ -320,6 +335,71 @@ forces a sub-buffer switch on all the channel buffers, and can be used to finalize and process the last sub-buffers before the channel is closed. +Creating non-relay files +------------------------ + +relay_open() automatically creates files in the relayfs filesystem to +represent the per-cpu kernel buffers; it's often useful for +applications to be able to create their own files alongside the relay +files in the relayfs filesystem as well e.g. 'control' files much like +those created in /proc or debugfs for similar purposes, used to +communicate control information between the kernel and user sides of a +relayfs application. For this purpose the relayfs_create_file() and +relayfs_remove_file() API functions exist. For relayfs_create_file(), +the caller passes in a set of user-defined file operations to be used +for the file and an optional void * to a user-specified data item, +which will be accessible via inode->u.generic_ip (see the relay-apps +tarball for examples). The file_operations are a required parameter +to relayfs_create_file() and thus the semantics of these files are +completely defined by the caller. + +See the relay-apps tarball at http://relayfs.sourceforge.net for +examples of how these non-relay files are meant to be used. + +Creating relay files in other filesystems +----------------------------------------- + +By default of course, relay_open() creates relay files in the relayfs +filesystem. Because relay_file_operations is exported, however, it's +also possible to create and use relay files in other pseudo-filesytems +such as debugfs. + +For this purpose, two callback functions are provided, +create_buf_file() and remove_buf_file(). create_buf_file() is called +once for each per-cpu buffer from relay_open() to allow the client to +create a file to be used to represent the corresponding buffer; if +this callback is not defined, the default implementation will create +and return a file in the relayfs filesystem to represent the buffer. +The callback should return the dentry of the file created to represent +the relay buffer. Note that the parent directory passed to +relay_open() (and passed along to the callback), if specified, must +exist in the same filesystem the new relay file is created in. If +create_buf_file() is defined, remove_buf_file() must also be defined; +it's responsible for deleting the file(s) created in create_buf_file() +and is called during relay_close(). + +The create_buf_file() implementation can also be defined in such a way +as to allow the creation of a single 'global' buffer instead of the +default per-cpu set. This can be useful for applications interested +mainly in seeing the relative ordering of system-wide events without +the need to bother with saving explicit timestamps for the purpose of +merging/sorting per-cpu files in a postprocessing step. + +To have relay_open() create a global buffer, the create_buf_file() +implementation should set the value of the is_global outparam to a +non-zero value in addition to creating the file that will be used to +represent the single buffer. In the case of a global buffer, +create_buf_file() and remove_buf_file() will be called only once. The +normal channel-writing functions e.g. relay_write() can still be used +- writes from any cpu will transparently end up in the global buffer - +but since it is a global buffer, callers should make sure they use the +proper locking for such a buffer, either by wrapping writes in a +spinlock, or by copying a write function from relayfs_fs.h and +creating a local version that internally does the proper locking. + +See the 'exported-relayfile' examples in the relay-apps tarball for +examples of creating and using relay files in debugfs. + Misc ---- diff --git a/Documentation/filesystems/spufs.txt b/Documentation/filesystems/spufs.txt new file mode 100644 index 00000000000000..8edc3952eff466 --- /dev/null +++ b/Documentation/filesystems/spufs.txt @@ -0,0 +1,521 @@ +SPUFS(2) Linux Programmer's Manual SPUFS(2) + + + +NAME + spufs - the SPU file system + + +DESCRIPTION + The SPU file system is used on PowerPC machines that implement the Cell + Broadband Engine Architecture in order to access Synergistic Processor + Units (SPUs). + + The file system provides a name space similar to posix shared memory or + message queues. Users that have write permissions on the file system + can use spu_create(2) to establish SPU contexts in the spufs root. + + Every SPU context is represented by a directory containing a predefined + set of files. These files can be used for manipulating the state of the + logical SPU. Users can change permissions on those files, but not actu- + ally add or remove files. + + +MOUNT OPTIONS + uid=<uid> + set the user owning the mount point, the default is 0 (root). + + gid=<gid> + set the group owning the mount point, the default is 0 (root). + + +FILES + The files in spufs mostly follow the standard behavior for regular sys- + tem calls like read(2) or write(2), but often support only a subset of + the operations supported on regular file systems. This list details the + supported operations and the deviations from the behaviour in the + respective man pages. + + All files that support the read(2) operation also support readv(2) and + all files that support the write(2) operation also support writev(2). + All files support the access(2) and stat(2) family of operations, but + only the st_mode, st_nlink, st_uid and st_gid fields of struct stat + contain reliable information. + + All files support the chmod(2)/fchmod(2) and chown(2)/fchown(2) opera- + tions, but will not be able to grant permissions that contradict the + possible operations, e.g. read access on the wbox file. + + The current set of files is: + + + /mem + the contents of the local storage memory of the SPU. This can be + accessed like a regular shared memory file and contains both code and + data in the address space of the SPU. The possible operations on an + open mem file are: + + read(2), pread(2), write(2), pwrite(2), lseek(2) + These operate as documented, with the exception that seek(2), + write(2) and pwrite(2) are not supported beyond the end of the + file. The file size is the size of the local storage of the SPU, + which normally is 256 kilobytes. + + mmap(2) + Mapping mem into the process address space gives access to the + SPU local storage within the process address space. Only + MAP_SHARED mappings are allowed. + + + /mbox + The first SPU to CPU communication mailbox. This file is read-only and + can be read in units of 32 bits. The file can only be used in non- + blocking mode and it even poll() will not block on it. The possible + operations on an open mbox file are: + + read(2) + If a count smaller than four is requested, read returns -1 and + sets errno to EINVAL. If there is no data available in the mail + box, the return value is set to -1 and errno becomes EAGAIN. + When data has been read successfully, four bytes are placed in + the data buffer and the value four is returned. + + + /ibox + The second SPU to CPU communication mailbox. This file is similar to + the first mailbox file, but can be read in blocking I/O mode, and the + poll familiy of system calls can be used to wait for it. The possible + operations on an open ibox file are: + + read(2) + If a count smaller than four is requested, read returns -1 and + sets errno to EINVAL. If there is no data available in the mail + box and the file descriptor has been opened with O_NONBLOCK, the + return value is set to -1 and errno becomes EAGAIN. + + If there is no data available in the mail box and the file + descriptor has been opened without O_NONBLOCK, the call will + block until the SPU writes to its interrupt mailbox channel. + When data has been read successfully, four bytes are placed in + the data buffer and the value four is returned. + + poll(2) + Poll on the ibox file returns (POLLIN | POLLRDNORM) whenever + data is available for reading. + + + /wbox + The CPU to SPU communation mailbox. It is write-only can can be written + in units of 32 bits. If the mailbox is full, write() will block and + poll can be used to wait for it becoming empty again. The possible + operations on an open wbox file are: write(2) If a count smaller than + four is requested, write returns -1 and sets errno to EINVAL. If there + is no space available in the mail box and the file descriptor has been + opened with O_NONBLOCK, the return value is set to -1 and errno becomes + EAGAIN. + + If there is no space available in the mail box and the file descriptor + has been opened without O_NONBLOCK, the call will block until the SPU + reads from its PPE mailbox channel. When data has been read success- + fully, four bytes are placed in the data buffer and the value four is + returned. + + poll(2) + Poll on the ibox file returns (POLLOUT | POLLWRNORM) whenever + space is available for writing. + + + /mbox_stat + /ibox_stat + /wbox_stat + Read-only files that contain the length of the current queue, i.e. how + many words can be read from mbox or ibox or how many words can be + written to wbox without blocking. The files can be read only in 4-byte + units and return a big-endian binary integer number. The possible + operations on an open *box_stat file are: + + read(2) + If a count smaller than four is requested, read returns -1 and + sets errno to EINVAL. Otherwise, a four byte value is placed in + the data buffer, containing the number of elements that can be + read from (for mbox_stat and ibox_stat) or written to (for + wbox_stat) the respective mail box without blocking or resulting + in EAGAIN. + + + /npc + /decr + /decr_status + /spu_tag_mask + /event_mask + /srr0 + Internal registers of the SPU. The representation is an ASCII string + with the numeric value of the next instruction to be executed. These + can be used in read/write mode for debugging, but normal operation of + programs should not rely on them because access to any of them except + npc requires an SPU context save and is therefore very inefficient. + + The contents of these files are: + + npc Next Program Counter + + decr SPU Decrementer + + decr_status Decrementer Status + + spu_tag_mask MFC tag mask for SPU DMA + + event_mask Event mask for SPU interrupts + + srr0 Interrupt Return address register + + + The possible operations on an open npc, decr, decr_status, + spu_tag_mask, event_mask or srr0 file are: + + read(2) + When the count supplied to the read call is shorter than the + required length for the pointer value plus a newline character, + subsequent reads from the same file descriptor will result in + completing the string, regardless of changes to the register by + a running SPU task. When a complete string has been read, all + subsequent read operations will return zero bytes and a new file + descriptor needs to be opened to read the value again. + + write(2) + A write operation on the file results in setting the register to + the value given in the string. The string is parsed from the + beginning to the first non-numeric character or the end of the + buffer. Subsequent writes to the same file descriptor overwrite + the previous setting. + + + /fpcr + This file gives access to the Floating Point Status and Control Regis- + ter as a four byte long file. The operations on the fpcr file are: + + read(2) + If a count smaller than four is requested, read returns -1 and + sets errno to EINVAL. Otherwise, a four byte value is placed in + the data buffer, containing the current value of the fpcr regis- + ter. + + write(2) + If a count smaller than four is requested, write returns -1 and + sets errno to EINVAL. Otherwise, a four byte value is copied + from the data buffer, updating the value of the fpcr register. + + + /signal1 + /signal2 + The two signal notification channels of an SPU. These are read-write + files that operate on a 32 bit word. Writing to one of these files + triggers an interrupt on the SPU. The value writting to the signal + files can be read from the SPU through a channel read or from host user + space through the file. After the value has been read by the SPU, it + is reset to zero. The possible operations on an open signal1 or sig- + nal2 file are: + + read(2) + If a count smaller than four is requested, read returns -1 and + sets errno to EINVAL. Otherwise, a four byte value is placed in + the data buffer, containing the current value of the specified + signal notification register. + + write(2) + If a count smaller than four is requested, write returns -1 and + sets errno to EINVAL. Otherwise, a four byte value is copied + from the data buffer, updating the value of the specified signal + notification register. The signal notification register will + either be replaced with the input data or will be updated to the + bitwise OR or the old value and the input data, depending on the + contents of the signal1_type, or signal2_type respectively, + file. + + + /signal1_type + /signal2_type + These two files change the behavior of the signal1 and signal2 notifi- + cation files. The contain a numerical ASCII string which is read as + either "1" or "0". In mode 0 (overwrite), the hardware replaces the + contents of the signal channel with the data that is written to it. in + mode 1 (logical OR), the hardware accumulates the bits that are subse- + quently written to it. The possible operations on an open signal1_type + or signal2_type file are: + + read(2) + When the count supplied to the read call is shorter than the + required length for the digit plus a newline character, subse- + quent reads from the same file descriptor will result in com- + pleting the string. When a complete string has been read, all + subsequent read operations will return zero bytes and a new file + descriptor needs to be opened to read the value again. + + write(2) + A write operation on the file results in setting the register to + the value given in the string. The string is parsed from the + beginning to the first non-numeric character or the end of the + buffer. Subsequent writes to the same file descriptor overwrite + the previous setting. + + +EXAMPLES + /etc/fstab entry + none /spu spufs gid=spu 0 0 + + +AUTHORS + Arnd Bergmann <arndb@de.ibm.com>, Mark Nutter <mnutter@us.ibm.com>, + Ulrich Weigand <Ulrich.Weigand@de.ibm.com> + +SEE ALSO + capabilities(7), close(2), spu_create(2), spu_run(2), spufs(7) + + + +Linux 2005-09-28 SPUFS(2) + +------------------------------------------------------------------------------ + +SPU_RUN(2) Linux Programmer's Manual SPU_RUN(2) + + + +NAME + spu_run - execute an spu context + + +SYNOPSIS + #include <sys/spu.h> + + int spu_run(int fd, unsigned int *npc, unsigned int *event); + +DESCRIPTION + The spu_run system call is used on PowerPC machines that implement the + Cell Broadband Engine Architecture in order to access Synergistic Pro- + cessor Units (SPUs). It uses the fd that was returned from spu_cre- + ate(2) to address a specific SPU context. When the context gets sched- + uled to a physical SPU, it starts execution at the instruction pointer + passed in npc. + + Execution of SPU code happens synchronously, meaning that spu_run does + not return while the SPU is still running. If there is a need to exe- + cute SPU code in parallel with other code on either the main CPU or + other SPUs, you need to create a new thread of execution first, e.g. + using the pthread_create(3) call. + + When spu_run returns, the current value of the SPU instruction pointer + is written back to npc, so you can call spu_run again without updating + the pointers. + + event can be a NULL pointer or point to an extended status code that + gets filled when spu_run returns. It can be one of the following con- + stants: + + SPE_EVENT_DMA_ALIGNMENT + A DMA alignment error + + SPE_EVENT_SPE_DATA_SEGMENT + A DMA segmentation error + + SPE_EVENT_SPE_DATA_STORAGE + A DMA storage error + + If NULL is passed as the event argument, these errors will result in a + signal delivered to the calling process. + +RETURN VALUE + spu_run returns the value of the spu_status register or -1 to indicate + an error and set errno to one of the error codes listed below. The + spu_status register value contains a bit mask of status codes and + optionally a 14 bit code returned from the stop-and-signal instruction + on the SPU. The bit masks for the status codes are: + + 0x02 SPU was stopped by stop-and-signal. + + 0x04 SPU was stopped by halt. + + 0x08 SPU is waiting for a channel. + + 0x10 SPU is in single-step mode. + + 0x20 SPU has tried to execute an invalid instruction. + + 0x40 SPU has tried to access an invalid channel. + + 0x3fff0000 + The bits masked with this value contain the code returned from + stop-and-signal. + + There are always one or more of the lower eight bits set or an error + code is returned from spu_run. + +ERRORS + EAGAIN or EWOULDBLOCK + fd is in non-blocking mode and spu_run would block. + + EBADF fd is not a valid file descriptor. + + EFAULT npc is not a valid pointer or status is neither NULL nor a valid + pointer. + + EINTR A signal occured while spu_run was in progress. The npc value + has been updated to the new program counter value if necessary. + + EINVAL fd is not a file descriptor returned from spu_create(2). + + ENOMEM Insufficient memory was available to handle a page fault result- + ing from an MFC direct memory access. + + ENOSYS the functionality is not provided by the current system, because + either the hardware does not provide SPUs or the spufs module is + not loaded. + + +NOTES + spu_run is meant to be used from libraries that implement a more + abstract interface to SPUs, not to be used from regular applications. + See http://www.bsc.es/projects/deepcomputing/linuxoncell/ for the rec- + ommended libraries. + + +CONFORMING TO + This call is Linux specific and only implemented by the ppc64 architec- + ture. Programs using this system call are not portable. + + +BUGS + The code does not yet fully implement all features lined out here. + + +AUTHOR + Arnd Bergmann <arndb@de.ibm.com> + +SEE ALSO + capabilities(7), close(2), spu_create(2), spufs(7) + + + +Linux 2005-09-28 SPU_RUN(2) + +------------------------------------------------------------------------------ + +SPU_CREATE(2) Linux Programmer's Manual SPU_CREATE(2) + + + +NAME + spu_create - create a new spu context + + +SYNOPSIS + #include <sys/types.h> + #include <sys/spu.h> + + int spu_create(const char *pathname, int flags, mode_t mode); + +DESCRIPTION + The spu_create system call is used on PowerPC machines that implement + the Cell Broadband Engine Architecture in order to access Synergistic + Processor Units (SPUs). It creates a new logical context for an SPU in + pathname and returns a handle to associated with it. pathname must + point to a non-existing directory in the mount point of the SPU file + system (spufs). When spu_create is successful, a directory gets cre- + ated on pathname and it is populated with files. + + The returned file handle can only be passed to spu_run(2) or closed, + other operations are not defined on it. When it is closed, all associ- + ated directory entries in spufs are removed. When the last file handle + pointing either inside of the context directory or to this file + descriptor is closed, the logical SPU context is destroyed. + + The parameter flags can be zero or any bitwise or'd combination of the + following constants: + + SPU_RAWIO + Allow mapping of some of the hardware registers of the SPU into + user space. This flag requires the CAP_SYS_RAWIO capability, see + capabilities(7). + + The mode parameter specifies the permissions used for creating the new + directory in spufs. mode is modified with the user's umask(2) value + and then used for both the directory and the files contained in it. The + file permissions mask out some more bits of mode because they typically + support only read or write access. See stat(2) for a full list of the + possible mode values. + + +RETURN VALUE + spu_create returns a new file descriptor. It may return -1 to indicate + an error condition and set errno to one of the error codes listed + below. + + +ERRORS + EACCESS + The current user does not have write access on the spufs mount + point. + + EEXIST An SPU context already exists at the given path name. + + EFAULT pathname is not a valid string pointer in the current address + space. + + EINVAL pathname is not a directory in the spufs mount point. + + ELOOP Too many symlinks were found while resolving pathname. + + EMFILE The process has reached its maximum open file limit. + + ENAMETOOLONG + pathname was too long. + + ENFILE The system has reached the global open file limit. + + ENOENT Part of pathname could not be resolved. + + ENOMEM The kernel could not allocate all resources required. + + ENOSPC There are not enough SPU resources available to create a new + context or the user specific limit for the number of SPU con- + texts has been reached. + + ENOSYS the functionality is not provided by the current system, because + either the hardware does not provide SPUs or the spufs module is + not loaded. + + ENOTDIR + A part of pathname is not a directory. + + + +NOTES + spu_create is meant to be used from libraries that implement a more + abstract interface to SPUs, not to be used from regular applications. + See http://www.bsc.es/projects/deepcomputing/linuxoncell/ for the rec- + ommended libraries. + + +FILES + pathname must point to a location beneath the mount point of spufs. By + convention, it gets mounted in /spu. + + +CONFORMING TO + This call is Linux specific and only implemented by the ppc64 architec- + ture. Programs using this system call are not portable. + + +BUGS + The code does not yet fully implement all features lined out here. + + +AUTHOR + Arnd Bergmann <arndb@de.ibm.com> + +SEE ALSO + capabilities(7), close(2), spu_run(2), spufs(7) + + + +Linux 2005-09-28 SPU_CREATE(2) diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 988a62fae11f88..7ba2baa165ffdc 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt @@ -1,4 +1,5 @@ Accessing PCI device resources through sysfs +-------------------------------------------- sysfs, usually mounted at /sys, provides access to PCI resources on platforms that support it. For example, a given bus might look like this: @@ -47,14 +48,21 @@ files, each with their own function. binary - file contains binary data cpumask - file contains a cpumask type -The read only files are informational, writes to them will be ignored. -Writable files can be used to perform actions on the device (e.g. changing -config space, detaching a device). mmapable files are available via an -mmap of the file at offset 0 and can be used to do actual device programming -from userspace. Note that some platforms don't support mmapping of certain -resources, so be sure to check the return value from any attempted mmap. +The read only files are informational, writes to them will be ignored, with +the exception of the 'rom' file. Writable files can be used to perform +actions on the device (e.g. changing config space, detaching a device). +mmapable files are available via an mmap of the file at offset 0 and can be +used to do actual device programming from userspace. Note that some platforms +don't support mmapping of certain resources, so be sure to check the return +value from any attempted mmap. + +The 'rom' file is special in that it provides read-only access to the device's +ROM file, if available. It's disabled by default, however, so applications +should write the string "1" to the file to enable it before attempting a read +call, and disable it following the access by writing "0" to the file. Accessing legacy resources through sysfs +---------------------------------------- Legacy I/O port and ISA memory resources are also provided in sysfs if the underlying platform supports them. They're located in the PCI class heirarchy, @@ -75,6 +83,7 @@ simply dereference the returned pointer (after checking for errors of course) to access legacy memory space. Supporting PCI access on new platforms +-------------------------------------- In order to support PCI resource mapping as described above, Linux platform code must define HAVE_PCI_MMAP and provide a pci_mmap_page_range function. diff --git a/Documentation/hrtimers.txt b/Documentation/hrtimers.txt new file mode 100644 index 00000000000000..7620ff735faf93 --- /dev/null +++ b/Documentation/hrtimers.txt @@ -0,0 +1,178 @@ + +hrtimers - subsystem for high-resolution kernel timers +---------------------------------------------------- + +This patch introduces a new subsystem for high-resolution kernel timers. + +One might ask the question: we already have a timer subsystem +(kernel/timers.c), why do we need two timer subsystems? After a lot of +back and forth trying to integrate high-resolution and high-precision +features into the existing timer framework, and after testing various +such high-resolution timer implementations in practice, we came to the +conclusion that the timer wheel code is fundamentally not suitable for +such an approach. We initially didnt believe this ('there must be a way +to solve this'), and spent a considerable effort trying to integrate +things into the timer wheel, but we failed. In hindsight, there are +several reasons why such integration is hard/impossible: + +- the forced handling of low-resolution and high-resolution timers in + the same way leads to a lot of compromises, macro magic and #ifdef + mess. The timers.c code is very "tightly coded" around jiffies and + 32-bitness assumptions, and has been honed and micro-optimized for a + relatively narrow use case (jiffies in a relatively narrow HZ range) + for many years - and thus even small extensions to it easily break + the wheel concept, leading to even worse compromises. The timer wheel + code is very good and tight code, there's zero problems with it in its + current usage - but it is simply not suitable to be extended for + high-res timers. + +- the unpredictable [O(N)] overhead of cascading leads to delays which + necessiate a more complex handling of high resolution timers, which + in turn decreases robustness. Such a design still led to rather large + timing inaccuracies. Cascading is a fundamental property of the timer + wheel concept, it cannot be 'designed out' without unevitably + degrading other portions of the timers.c code in an unacceptable way. + +- the implementation of the current posix-timer subsystem on top of + the timer wheel has already introduced a quite complex handling of + the required readjusting of absolute CLOCK_REALTIME timers at + settimeofday or NTP time - further underlying our experience by + example: that the timer wheel data structure is too rigid for high-res + timers. + +- the timer wheel code is most optimal for use cases which can be + identified as "timeouts". Such timeouts are usually set up to cover + error conditions in various I/O paths, such as networking and block + I/O. The vast majority of those timers never expire and are rarely + recascaded because the expected correct event arrives in time so they + can be removed from the timer wheel before any further processing of + them becomes necessary. Thus the users of these timeouts can accept + the granularity and precision tradeoffs of the timer wheel, and + largely expect the timer subsystem to have near-zero overhead. + Accurate timing for them is not a core purpose - in fact most of the + timeout values used are ad-hoc. For them it is at most a necessary + evil to guarantee the processing of actual timeout completions + (because most of the timeouts are deleted before completion), which + should thus be as cheap and unintrusive as possible. + +The primary users of precision timers are user-space applications that +utilize nanosleep, posix-timers and itimer interfaces. Also, in-kernel +users like drivers and subsystems which require precise timed events +(e.g. multimedia) can benefit from the availability of a seperate +high-resolution timer subsystem as well. + +While this subsystem does not offer high-resolution clock sources just +yet, the hrtimer subsystem can be easily extended with high-resolution +clock capabilities, and patches for that exist and are maturing quickly. +The increasing demand for realtime and multimedia applications along +with other potential users for precise timers gives another reason to +separate the "timeout" and "precise timer" subsystems. + +Another potential benefit is that such a seperation allows even more +special-purpose optimization of the existing timer wheel for the low +resolution and low precision use cases - once the precision-sensitive +APIs are separated from the timer wheel and are migrated over to +hrtimers. E.g. we could decrease the frequency of the timeout subsystem +from 250 Hz to 100 HZ (or even smaller). + +hrtimer subsystem implementation details +---------------------------------------- + +the basic design considerations were: + +- simplicity + +- data structure not bound to jiffies or any other granularity. All the + kernel logic works at 64-bit nanoseconds resolution - no compromises. + +- simplification of existing, timing related kernel code + +another basic requirement was the immediate enqueueing and ordering of +timers at activation time. After looking at several possible solutions +such as radix trees and hashes, we chose the red black tree as the basic +data structure. Rbtrees are available as a library in the kernel and are +used in various performance-critical areas of e.g. memory management and +file systems. The rbtree is solely used for time sorted ordering, while +a separate list is used to give the expiry code fast access to the +queued timers, without having to walk the rbtree. + +(This seperate list is also useful for later when we'll introduce +high-resolution clocks, where we need seperate pending and expired +queues while keeping the time-order intact.) + +Time-ordered enqueueing is not purely for the purposes of +high-resolution clocks though, it also simplifies the handling of +absolute timers based on a low-resolution CLOCK_REALTIME. The existing +implementation needed to keep an extra list of all armed absolute +CLOCK_REALTIME timers along with complex locking. In case of +settimeofday and NTP, all the timers (!) had to be dequeued, the +time-changing code had to fix them up one by one, and all of them had to +be enqueued again. The time-ordered enqueueing and the storage of the +expiry time in absolute time units removes all this complex and poorly +scaling code from the posix-timer implementation - the clock can simply +be set without having to touch the rbtree. This also makes the handling +of posix-timers simpler in general. + +The locking and per-CPU behavior of hrtimers was mostly taken from the +existing timer wheel code, as it is mature and well suited. Sharing code +was not really a win, due to the different data structures. Also, the +hrtimer functions now have clearer behavior and clearer names - such as +hrtimer_try_to_cancel() and hrtimer_cancel() [which are roughly +equivalent to del_timer() and del_timer_sync()] - so there's no direct +1:1 mapping between them on the algorithmical level, and thus no real +potential for code sharing either. + +Basic data types: every time value, absolute or relative, is in a +special nanosecond-resolution type: ktime_t. The kernel-internal +representation of ktime_t values and operations is implemented via +macros and inline functions, and can be switched between a "hybrid +union" type and a plain "scalar" 64bit nanoseconds representation (at +compile time). The hybrid union type optimizes time conversions on 32bit +CPUs. This build-time-selectable ktime_t storage format was implemented +to avoid the performance impact of 64-bit multiplications and divisions +on 32bit CPUs. Such operations are frequently necessary to convert +between the storage formats provided by kernel and userspace interfaces +and the internal time format. (See include/linux/ktime.h for further +details.) + +hrtimers - rounding of timer values +----------------------------------- + +the hrtimer code will round timer events to lower-resolution clocks +because it has to. Otherwise it will do no artificial rounding at all. + +one question is, what resolution value should be returned to the user by +the clock_getres() interface. This will return whatever real resolution +a given clock has - be it low-res, high-res, or artificially-low-res. + +hrtimers - testing and verification +---------------------------------- + +We used the high-resolution clock subsystem ontop of hrtimers to verify +the hrtimer implementation details in praxis, and we also ran the posix +timer tests in order to ensure specification compliance. We also ran +tests on low-resolution clocks. + +The hrtimer patch converts the following kernel functionality to use +hrtimers: + + - nanosleep + - itimers + - posix-timers + +The conversion of nanosleep and posix-timers enabled the unification of +nanosleep and clock_nanosleep. + +The code was successfully compiled for the following platforms: + + i386, x86_64, ARM, PPC, PPC64, IA64 + +The code was run-tested on the following platforms: + + i386(UP/SMP), x86_64(UP/SMP), ARM, PPC + +hrtimers were also integrated into the -rt tree, along with a +hrtimers-based high-resolution clock implementation, so the hrtimers +code got a healthy amount of testing and use in practice. + + Thomas Gleixner, Ingo Molnar diff --git a/Documentation/hwmon/w83627hf b/Documentation/hwmon/w83627hf index 78f37c2d602e0a..5d23776e99076b 100644 --- a/Documentation/hwmon/w83627hf +++ b/Documentation/hwmon/w83627hf @@ -54,13 +54,16 @@ If you really want i2c accesses for these Super I/O chips, use the w83781d driver. However this is not the preferred method now that this ISA driver has been developed. -Technically, the w83627thf does not support a VID reading. However, it's -possible or even likely that your mainboard maker has routed these signals -to a specific set of general purpose IO pins (the Asus P4C800-E is one such -board). The w83627thf driver now interprets these as VID. If the VID on -your board doesn't work, first see doc/vid in the lm_sensors package. If -that still doesn't help, email us at lm-sensors@lm-sensors.org. +The w83627_HF_ uses pins 110-106 as VID0-VID4. The w83627_THF_ uses the +same pins as GPIO[0:4]. Technically, the w83627_THF_ does not support a +VID reading. However the two chips have the identical 128 pin package. So, +it is possible or even likely for a w83627thf to have the VID signals routed +to these pins despite their not being labeled for that purpose. Therefore, +the w83627thf driver interprets these as VID. If the VID on your board +doesn't work, first see doc/vid in the lm_sensors package[1]. If that still +doesn't help, you may just ignore the bogus VID reading with no harm done. -For further information on this driver see the w83781d driver -documentation. +For further information on this driver see the w83781d driver documentation. + +[1] http://www2.lm-sensors.nu/~lm78/cvs/browse.cgi/lm_sensors2/doc/vid diff --git a/Documentation/i2c/busses/i2c-nforce2 b/Documentation/i2c/busses/i2c-nforce2 index e379e182e64f4f..d751282d9b2a66 100644 --- a/Documentation/i2c/busses/i2c-nforce2 +++ b/Documentation/i2c/busses/i2c-nforce2 @@ -5,7 +5,8 @@ Supported adapters: * nForce2 Ultra 400 MCP 10de:0084 * nForce3 Pro150 MCP 10de:00D4 * nForce3 250Gb MCP 10de:00E4 - * nForce4 MCP 10de:0052 + * nForce4 MCP 10de:0052 + * nForce4 MCP-04 10de:0034 Datasheet: not publically available, but seems to be similar to the AMD-8111 SMBus 2.0 adapter. diff --git a/Documentation/i2c/busses/i2c-parport b/Documentation/i2c/busses/i2c-parport index 9f1d0082da18b4..d9f23c0763f1c2 100644 --- a/Documentation/i2c/busses/i2c-parport +++ b/Documentation/i2c/busses/i2c-parport @@ -17,6 +17,7 @@ It currently supports the following devices: * Velleman K8000 adapter * ELV adapter * Analog Devices evaluation boards (ADM1025, ADM1030, ADM1031, ADM1032) + * Barco LPT->DVI (K5800236) adapter These devices use different pinout configurations, so you have to tell the driver what you have, using the type module parameter. There is no diff --git a/Documentation/i2c/porting-clients b/Documentation/i2c/porting-clients index 184fac2377aa19..f03c2a02f80668 100644 --- a/Documentation/i2c/porting-clients +++ b/Documentation/i2c/porting-clients @@ -1,10 +1,13 @@ -Revision 5, 2005-07-29 +Revision 6, 2005-11-20 Jean Delvare <khali@linux-fr.org> Greg KH <greg@kroah.com> This is a guide on how to convert I2C chip drivers from Linux 2.4 to Linux 2.6. I have been using existing drivers (lm75, lm78) as examples. Then I converted a driver myself (lm83) and updated this document. +Note that this guide is strongly oriented towards hardware monitoring +drivers. Many points are still valid for other type of drivers, but +others may be irrelevant. There are two sets of points below. The first set concerns technical changes. The second set concerns coding policy. Both are mandatory. @@ -22,16 +25,20 @@ Technical changes: #include <linux/module.h> #include <linux/init.h> #include <linux/slab.h> + #include <linux/jiffies.h> #include <linux/i2c.h> + #include <linux/i2c-isa.h> /* for ISA drivers */ #include <linux/hwmon.h> /* for hardware monitoring drivers */ #include <linux/hwmon-sysfs.h> #include <linux/hwmon-vid.h> /* if you need VRM support */ + #include <linux/err.h> /* for class registration */ #include <asm/io.h> /* if you have I/O operations */ Please respect this inclusion order. Some extra headers may be required for a given driver (e.g. "lm75.h"). * [Addresses] SENSORS_I2C_END becomes I2C_CLIENT_END, ISA addresses - are no more handled by the i2c core. + are no more handled by the i2c core. Address ranges are no more + supported either, define each individual address separately. SENSORS_INSMOD_<n> becomes I2C_CLIENT_INSMOD_<n>. * [Client data] Get rid of sysctl_id. Try using standard names for @@ -48,23 +55,23 @@ Technical changes: int kind); static void lm75_init_client(struct i2c_client *client); static int lm75_detach_client(struct i2c_client *client); - static void lm75_update_client(struct i2c_client *client); + static struct lm75_data lm75_update_device(struct device *dev); * [Sysctl] All sysctl stuff is of course gone (defines, ctl_table and functions). Instead, you have to define show and set functions for each sysfs file. Only define set for writable values. Take a look at an - existing 2.6 driver for details (lm78 for example). Don't forget + existing 2.6 driver for details (it87 for example). Don't forget to define the attributes for each file (this is that step that links callback functions). Use the file names specified in - Documentation/i2c/sysfs-interface for the individual files. Also + Documentation/hwmon/sysfs-interface for the individual files. Also convert the units these files read and write to the specified ones. If you need to add a new type of file, please discuss it on the sensors mailing list <lm-sensors@lm-sensors.org> by providing a - patch to the Documentation/i2c/sysfs-interface file. + patch to the Documentation/hwmon/sysfs-interface file. * [Attach] For I2C drivers, the attach function should make sure - that the adapter's class has I2C_CLASS_HWMON, using the - following construct: + that the adapter's class has I2C_CLASS_HWMON (or whatever class is + suitable for your driver), using the following construct: if (!(adapter->class & I2C_CLASS_HWMON)) return 0; ISA-only drivers of course don't need this. @@ -72,63 +79,72 @@ Technical changes: * [Detect] As mentioned earlier, the flags parameter is gone. The type_name and client_name strings are replaced by a single - name string, which will be filled with a lowercase, short string - (typically the driver name, e.g. "lm75"). + name string, which will be filled with a lowercase, short string. In i2c-only drivers, drop the i2c_is_isa_adapter check, it's useless. Same for isa-only drivers, as the test would always be true. Only hybrid drivers (which are quite rare) still need it. - The errorN labels are reduced to the number needed. If that number - is 2 (i2c-only drivers), it is advised that the labels are named - exit and exit_free. For i2c+isa drivers, labels should be named - ERROR0, ERROR1 and ERROR2. Don't forget to properly set err before + The labels used for error paths are reduced to the number needed. + It is advised that the labels are given descriptive names such as + exit and exit_free. Don't forget to properly set err before jumping to error labels. By the way, labels should be left-aligned. Use kzalloc instead of kmalloc. Use i2c_set_clientdata to set the client data (as opposed to a direct access to client->data). - Use strlcpy instead of strcpy to copy the client name. + Use strlcpy instead of strcpy or snprintf to copy the client name. Replace the sysctl directory registration by calls to device_create_file. Move the driver initialization before any sysfs file creation. + Register the client with the hwmon class (using hwmon_device_register) + if applicable. Drop client->id. Drop any 24RF08 corruption prevention you find, as this is now done at the i2c-core level, and doing it twice voids it. + Don't add I2C_CLIENT_ALLOW_USE to client->flags, it's the default now. * [Init] Limits must not be set by the driver (can be done later in user-space). Chip should not be reset default (although a module - parameter may be used to force is), and initialization should be + parameter may be used to force it), and initialization should be limited to the strictly necessary steps. -* [Detach] Get rid of data, remove the call to - i2c_deregister_entry. Do not log an error message if - i2c_detach_client fails, as i2c-core will now do it for you. - -* [Update] Don't access client->data directly, use - i2c_get_clientdata(client) instead. - -* [Interface] Init function should not print anything. Make sure - there is a MODULE_LICENSE() line, at the bottom of the file - (after MODULE_AUTHOR() and MODULE_DESCRIPTION(), in this order). +* [Detach] Remove the call to i2c_deregister_entry. Do not log an + error message if i2c_detach_client fails, as i2c-core will now do + it for you. + Unregister from the hwmon class if applicable. + +* [Update] The function prototype changed, it is now + passed a device structure, which you have to convert to a client + using to_i2c_client(dev). The update function should return a + pointer to the client data. + Don't access client->data directly, use i2c_get_clientdata(client) + instead. + Use time_after() instead of direct jiffies comparison. + +* [Interface] Make sure there is a MODULE_LICENSE() line, at the bottom + of the file (after MODULE_AUTHOR() and MODULE_DESCRIPTION(), in this + order). + +* [Driver] The flags field of the i2c_driver structure is gone. + I2C_DF_NOTIFY is now the default behavior. + The i2c_driver structure has a driver member, which is itself a + structure, those name member should be initialized to a driver name + string. i2c_driver itself has no name member anymore. Coding policy: * [Copyright] Use (C), not (c), for copyright. * [Debug/log] Get rid of #ifdef DEBUG/#endif constructs whenever you - can. Calls to printk/pr_debug for debugging purposes are replaced - by calls to dev_dbg. Here is an example on how to call it (taken - from lm75_detect): + can. Calls to printk for debugging purposes are replaced by calls to + dev_dbg where possible, else to pr_debug. Here is an example of how + to call it (taken from lm75_detect): dev_dbg(&client->dev, "Starting lm75 update\n"); Replace other printk calls with the dev_info, dev_err or dev_warn function, as appropriate. -* [Constants] Constants defines (registers, conversions, initial - values) should be aligned. This greatly improves readability. - Same goes for variables declarations. Alignments are achieved by the - means of tabs, not spaces. Remember that tabs are set to 8 in the - Linux kernel code. - -* [Structure definition] The name field should be standardized. All - lowercase and as simple as the driver name itself (e.g. "lm75"). +* [Constants] Constants defines (registers, conversions) should be + aligned. This greatly improves readability. + Alignments are achieved by the means of tabs, not spaces. Remember + that tabs are set to 8 in the Linux kernel code. * [Layout] Avoid extra empty lines between comments and what they comment. Respect the coding style (see Documentation/CodingStyle), diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients index d19993cc060418..3a057c8e5507c4 100644 --- a/Documentation/i2c/writing-clients +++ b/Documentation/i2c/writing-clients @@ -25,9 +25,9 @@ routines, a client structure specific information like the actual I2C address. static struct i2c_driver foo_driver = { - .owner = THIS_MODULE, - .name = "Foo version 2.3 driver", - .flags = I2C_DF_NOTIFY, + .driver = { + .name = "foo", + }, .attach_adapter = &foo_attach_adapter, .detach_client = &foo_detach_client, .command = &foo_command /* may be NULL */ @@ -36,10 +36,6 @@ static struct i2c_driver foo_driver = { The name field must match the driver name, including the case. It must not contain spaces, and may be up to 31 characters long. -Don't worry about the flags field; just put I2C_DF_NOTIFY into it. This -means that your driver will be notified when new adapters are found. -This is almost always what you want. - All other fields are for call-back functions which will be explained below. @@ -496,17 +492,13 @@ Note that some functions are marked by `__init', and some data structures by `__init_data'. Hose functions and structures can be removed after kernel booting (or module loading) is completed. + Command function ================ A generic ioctl-like function call back is supported. You will seldom -need this. You may even set it to NULL. - - /* No commands defined */ - int foo_command(struct i2c_client *client, unsigned int cmd, void *arg) - { - return 0; - } +need this, and its use is deprecated anyway, so newer design should not +use it. Set it to NULL. Sending and receiving diff --git a/Documentation/i2o/ioctl b/Documentation/i2o/ioctl index 3e174978997d35..1e77fac4e120b9 100644 --- a/Documentation/i2o/ioctl +++ b/Documentation/i2o/ioctl @@ -185,7 +185,7 @@ VII. Getting Parameters ENOMEM Kernel memory allocation error A return value of 0 does not mean that the value was actually - properly retreived. The user should check the result list + properly retrieved. The user should check the result list to determine the specific status of the transaction. VIII. Downloading Software diff --git a/Documentation/input/appletouch.txt b/Documentation/input/appletouch.txt index b48d11d0326d1b..4f7c633a76d287 100644 --- a/Documentation/input/appletouch.txt +++ b/Documentation/input/appletouch.txt @@ -3,7 +3,7 @@ Apple Touchpad Driver (appletouch) Copyright (C) 2005 Stelian Pop <stelian@popies.net> appletouch is a Linux kernel driver for the USB touchpad found on post -February 2005 Apple Alu Powerbooks. +February 2005 and October 2005 Apple Aluminium Powerbooks. This driver is derived from Johannes Berg's appletrackpad driver[1], but it has been improved in some areas: @@ -13,7 +13,8 @@ been improved in some areas: Credits go to Johannes Berg for reverse-engineering the touchpad protocol, Frank Arnold for further improvements, and Alex Harper for some additional -information about the inner workings of the touchpad sensors. +information about the inner workings of the touchpad sensors. Michael +Hanselmann added support for the October 2005 models. Usage: ------ diff --git a/Documentation/kdump/kdump.txt b/Documentation/kdump/kdump.txt index 5f08f9ce60464b..212cf3c21abf88 100644 --- a/Documentation/kdump/kdump.txt +++ b/Documentation/kdump/kdump.txt @@ -4,10 +4,10 @@ Documentation for kdump - the kexec-based crash dumping solution DESIGN ====== -Kdump uses kexec to reboot to a second kernel whenever a dump needs to be taken. -This second kernel is booted with very little memory. The first kernel reserves -the section of memory that the second kernel uses. This ensures that on-going -DMA from the first kernel does not corrupt the second kernel. +Kdump uses kexec to reboot to a second kernel whenever a dump needs to be +taken. This second kernel is booted with very little memory. The first kernel +reserves the section of memory that the second kernel uses. This ensures that +on-going DMA from the first kernel does not corrupt the second kernel. All the necessary information about Core image is encoded in ELF format and stored in reserved area of memory before crash. Physical address of start of @@ -35,77 +35,82 @@ In the second kernel, "old memory" can be accessed in two ways. SETUP ===== -1) Download http://www.xmission.com/~ebiederm/files/kexec/kexec-tools-1.101.tar.gz - and apply http://lse.sourceforge.net/kdump/patches/kexec-tools-1.101-kdump.patch - and after that build the source. +1) Download the upstream kexec-tools userspace package from + http://www.xmission.com/~ebiederm/files/kexec/kexec-tools-1.101.tar.gz. -2) Download and build the appropriate (2.6.13-rc1 onwards) vanilla kernel. + Apply the latest consolidated kdump patch on top of kexec-tools-1.101 + from http://lse.sourceforge.net/kdump/. This arrangment has been made + till all the userspace patches supporting kdump are integrated with + upstream kexec-tools userspace. +2) Download and build the appropriate (2.6.13-rc1 onwards) vanilla kernels. Two kernels need to be built in order to get this feature working. + Following are the steps to properly configure the two kernels specific + to kexec and kdump features: - A) First kernel: + A) First kernel or regular kernel: + ---------------------------------- a) Enable "kexec system call" feature (in Processor type and features). - CONFIG_KEXEC=y - b) This kernel's physical load address should be the default value of - 0x100000 (0x100000, 1 MB) (in Processor type and features). - CONFIG_PHYSICAL_START=0x100000 - c) Enable "sysfs file system support" (in Pseudo filesystems). - CONFIG_SYSFS=y + CONFIG_KEXEC=y + b) Enable "sysfs file system support" (in Pseudo filesystems). + CONFIG_SYSFS=y + c) make d) Boot into first kernel with the command line parameter "crashkernel=Y@X". Use appropriate values for X and Y. Y denotes how much memory to reserve - for the second kernel, and X denotes at what physical address the reserved - memory section starts. For example: "crashkernel=64M@16M". - - B) Second kernel: - a) Enable "kernel crash dumps" feature (in Processor type and features). - CONFIG_CRASH_DUMP=y - b) Specify a suitable value for "Physical address where the kernel is - loaded" (in Processor type and features). Typically this value - should be same as X (See option d) above, e.g., 16 MB or 0x1000000. - CONFIG_PHYSICAL_START=0x1000000 - c) Enable "/proc/vmcore support" (Optional, in Pseudo filesystems). - CONFIG_PROC_VMCORE=y - d) Disable SMP support and build a UP kernel (Until it is fixed). - CONFIG_SMP=n - e) Enable "Local APIC support on uniprocessors". - CONFIG_X86_UP_APIC=y - f) Enable "IO-APIC support on uniprocessors" - CONFIG_X86_UP_IOAPIC=y - - Note: i) Options a) and b) depend upon "Configure standard kernel features - (for small systems)" (under General setup). - ii) Option a) also depends on CONFIG_HIGHMEM (under Processor - type and features). - iii) Both option a) and b) are under "Processor type and features". - -3) Boot into the first kernel. You are now ready to try out kexec-based crash - dumps. - -4) Load the second kernel to be booted using: + for the second kernel, and X denotes at what physical address the + reserved memory section starts. For example: "crashkernel=64M@16M". + + + B) Second kernel or dump capture kernel: + --------------------------------------- + a) For i386 architecture enable Highmem support + CONFIG_HIGHMEM=y + b) Enable "kernel crash dumps" feature (under "Processor type and features") + CONFIG_CRASH_DUMP=y + c) Make sure a suitable value for "Physical address where the kernel is + loaded" (under "Processor type and features"). By default this value + is 0x1000000 (16MB) and it should be same as X (See option d above), + e.g., 16 MB or 0x1000000. + CONFIG_PHYSICAL_START=0x1000000 + d) Enable "/proc/vmcore support" (Optional, under "Pseudo filesystems"). + CONFIG_PROC_VMCORE=y + +3) After booting to regular kernel or first kernel, load the second kernel + using the following command: kexec -p <second-kernel> --args-linux --elf32-core-headers - --append="root=<root-dev> init 1 irqpoll" - - Note: i) <second-kernel> has to be a vmlinux image. bzImage will not work, - as of now. - ii) By default ELF headers are stored in ELF64 format. Option - --elf32-core-headers forces generation of ELF32 headers. gdb can - not open ELF64 headers on 32 bit systems. So creating ELF32 - headers can come handy for users who have got non-PAE systems and - hence have memory less than 4GB. - iii) Specify "irqpoll" as command line parameter. This reduces driver - initialization failures in second kernel due to shared interrupts. - iv) <root-dev> needs to be specified in a format corresponding to - the root device name in the output of mount command. - v) If you have built the drivers required to mount root file - system as modules in <second-kernel>, then, specify - --initrd=<initrd-for-second-kernel>. - -5) System reboots into the second kernel when a panic occurs. A module can be - written to force the panic or "ALT-SysRq-c" can be used initiate a crash - dump for testing purposes. - -6) Write out the dump file using + --append="root=<root-dev> init 1 irqpoll maxcpus=1" + + Notes: + ====== + i) <second-kernel> has to be a vmlinux image ie uncompressed elf image. + bzImage will not work, as of now. + ii) --args-linux has to be speicfied as if kexec it loading an elf image, + it needs to know that the arguments supplied are of linux type. + iii) By default ELF headers are stored in ELF64 format to support systems + with more than 4GB memory. Option --elf32-core-headers forces generation + of ELF32 headers. The reason for this option being, as of now gdb can + not open vmcore file with ELF64 headers on a 32 bit systems. So ELF32 + headers can be used if one has non-PAE systems and hence memory less + than 4GB. + iv) Specify "irqpoll" as command line parameter. This reduces driver + initialization failures in second kernel due to shared interrupts. + v) <root-dev> needs to be specified in a format corresponding to the root + device name in the output of mount command. + vi) If you have built the drivers required to mount root file system as + modules in <second-kernel>, then, specify + --initrd=<initrd-for-second-kernel>. + vii) Specify maxcpus=1 as, if during first kernel run, if panic happens on + non-boot cpus, second kernel doesn't seem to be boot up all the cpus. + The other option is to always built the second kernel without SMP + support ie CONFIG_SMP=n + +4) After successfully loading the second kernel as above, if a panic occurs + system reboots into the second kernel. A module can be written to force + the panic or "ALT-SysRq-c" can be used initiate a crash dump for testing + purposes. + +5) Once the second kernel has booted, write out the dump file using cp /proc/vmcore <dump-file> @@ -119,9 +124,9 @@ SETUP Entire memory: dd if=/dev/oldmem of=oldmem.001 + ANALYSIS ======== - Limited analysis can be done using gdb on the dump file copied out of /proc/vmcore. Use vmlinux built with -g and run @@ -132,15 +137,19 @@ work fine. Note: gdb cannot analyse core files generated in ELF64 format for i386. +Latest "crash" (crash-4.0-2.18) as available on Dave Anderson's site +http://people.redhat.com/~anderson/ works well with kdump format. + + TODO ==== - 1) Provide a kernel pages filtering mechanism so that core file size is not insane on systems having huge memory banks. -2) Modify "crash" tool to make it recognize this dump. +2) Relocatable kernel can help in maintaining multiple kernels for crashdump + and same kernel as the first kernel can be used to capture the dump. + CONTACT ======= - Vivek Goyal (vgoyal@in.ibm.com) Maneesh Soni (maneesh@in.ibm.com) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 61a56b100c62d2..dd0bfc291a682e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -475,10 +475,11 @@ running once the system is up. See Documentation/block/as-iosched.txt and Documentation/block/deadline-iosched.txt for details. - elfcorehdr= [IA-32] + elfcorehdr= [IA-32, X86_64] Specifies physical address of start of kernel core - image elf header. - See Documentation/kdump.txt for details. + image elf header. Generally kexec loader will + pass this option to capture kernel. + See Documentation/kdump/kdump.txt for details. enforcing [SELINUX] Set initial enforcing status. Format: {"0" | "1"} @@ -832,7 +833,7 @@ running once the system is up. mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel memory. - memmap=exactmap [KNL,IA-32] Enable setting of an exact + memmap=exactmap [KNL,IA-32,X86_64] Enable setting of an exact E820 memory map, as specified by the user. Such memmap=exactmap lines can be constructed based on BIOS output or other requirements. See the memmap=nn@ss @@ -910,6 +911,14 @@ running once the system is up. nfsroot= [NFS] nfs root filesystem for disk-less boxes. See Documentation/nfsroot.txt. + nfs.callback_tcpport= + [NFS] set the TCP port on which the NFSv4 callback + channel should listen. + + nfs.idmap_cache_timeout= + [NFS] set the maximum lifetime for idmapper cache + entries. + nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels no387 [BUGS=IA-32] Tells the kernel to use the 387 maths @@ -990,6 +999,8 @@ running once the system is up. nowb [ARM] + nr_uarts= [SERIAL] maximum number of UARTs to be registered. + opl3= [HW,OSS] Format: <io> @@ -1168,6 +1179,10 @@ running once the system is up. Limit processor to maximum C-state max_cstate=9 overrides any DMI blacklist limit. + processor.nocst [HW,ACPI] + Ignore the _CST method to determine C-states, + instead using the legacy FADT method + prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk before loading. See Documentation/ramdisk.txt. diff --git a/Documentation/keys-request-key.txt b/Documentation/keys-request-key.txt index 5f2b9c5edbb517..22488d7911681e 100644 --- a/Documentation/keys-request-key.txt +++ b/Documentation/keys-request-key.txt @@ -56,10 +56,12 @@ A request proceeds in the following manner: (4) request_key() then forks and executes /sbin/request-key with a new session keyring that contains a link to auth key V. - (5) /sbin/request-key execs an appropriate program to perform the actual + (5) /sbin/request-key assumes the authority associated with key U. + + (6) /sbin/request-key execs an appropriate program to perform the actual instantiation. - (6) The program may want to access another key from A's context (say a + (7) The program may want to access another key from A's context (say a Kerberos TGT key). It just requests the appropriate key, and the keyring search notes that the session keyring has auth key V in its bottom level. @@ -67,19 +69,19 @@ A request proceeds in the following manner: UID, GID, groups and security info of process A as if it was process A, and come up with key W. - (7) The program then does what it must to get the data with which to + (8) The program then does what it must to get the data with which to instantiate key U, using key W as a reference (perhaps it contacts a Kerberos server using the TGT) and then instantiates key U. - (8) Upon instantiating key U, auth key V is automatically revoked so that it + (9) Upon instantiating key U, auth key V is automatically revoked so that it may not be used again. - (9) The program then exits 0 and request_key() deletes key V and returns key +(10) The program then exits 0 and request_key() deletes key V and returns key U to the caller. -This also extends further. If key W (step 5 above) didn't exist, key W would be -created uninstantiated, another auth key (X) would be created [as per step 3] -and another copy of /sbin/request-key spawned [as per step 4]; but the context +This also extends further. If key W (step 7 above) didn't exist, key W would be +created uninstantiated, another auth key (X) would be created (as per step 3) +and another copy of /sbin/request-key spawned (as per step 4); but the context specified by auth key X will still be process A, as it was in auth key V. This is because process A's keyrings can't simply be attached to @@ -138,8 +140,8 @@ until one succeeds: (3) The process's session keyring is searched. - (4) If the process has a request_key() authorisation key in its session - keyring then: + (4) If the process has assumed the authority associated with a request_key() + authorisation key then: (a) If extant, the calling process's thread keyring is searched. diff --git a/Documentation/keys.txt b/Documentation/keys.txt index 31154882000a59..aaa01b0e3ee942 100644 --- a/Documentation/keys.txt +++ b/Documentation/keys.txt @@ -308,6 +308,8 @@ process making the call: KEY_SPEC_USER_KEYRING -4 UID-specific keyring KEY_SPEC_USER_SESSION_KEYRING -5 UID-session keyring KEY_SPEC_GROUP_KEYRING -6 GID-specific keyring + KEY_SPEC_REQKEY_AUTH_KEY -7 assumed request_key() + authorisation key The main syscalls are: @@ -498,7 +500,11 @@ The keyctl syscall functions are: keyring is full, error ENFILE will result. The link procedure checks the nesting of the keyrings, returning ELOOP if - it appears to deep or EDEADLK if the link would introduce a cycle. + it appears too deep or EDEADLK if the link would introduce a cycle. + + Any links within the keyring to keys that match the new key in terms of + type and description will be discarded from the keyring as the new one is + added. (*) Unlink a key or keyring from another keyring: @@ -628,6 +634,41 @@ The keyctl syscall functions are: there is one, otherwise the user default session keyring. + (*) Set the timeout on a key. + + long keyctl(KEYCTL_SET_TIMEOUT, key_serial_t key, unsigned timeout); + + This sets or clears the timeout on a key. The timeout can be 0 to clear + the timeout or a number of seconds to set the expiry time that far into + the future. + + The process must have attribute modification access on a key to set its + timeout. Timeouts may not be set with this function on negative, revoked + or expired keys. + + + (*) Assume the authority granted to instantiate a key + + long keyctl(KEYCTL_ASSUME_AUTHORITY, key_serial_t key); + + This assumes or divests the authority required to instantiate the + specified key. Authority can only be assumed if the thread has the + authorisation key associated with the specified key in its keyrings + somewhere. + + Once authority is assumed, searches for keys will also search the + requester's keyrings using the requester's security label, UID, GID and + groups. + + If the requested authority is unavailable, error EPERM will be returned, + likewise if the authority has been revoked because the target key is + already instantiated. + + If the specified key is 0, then any assumed authority will be divested. + + The assumed authorititive key is inherited across fork and exec. + + =============== KERNEL SERVICES =============== @@ -860,24 +901,6 @@ The structure has a number of fields, some of which are mandatory: It is safe to sleep in this method. - (*) int (*duplicate)(struct key *key, const struct key *source); - - If this type of key can be duplicated, then this method should be - provided. It is called to copy the payload attached to the source into the - new key. The data length on the new key will have been updated and the - quota adjusted already. - - This method will be called with the source key's semaphore read-locked to - prevent its payload from being changed, thus RCU constraints need not be - applied to the source key. - - This method does not have to lock the destination key in order to attach a - payload. The fact that KEY_FLAG_INSTANTIATED is not set in key->flags - prevents anything else from gaining access to the key. - - It is safe to sleep in this method. - - (*) int (*update)(struct key *key, const void *data, size_t datalen); If this type of key can be updated, then this method should be provided. diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt index 0541fe1de70482..0ea5a0c6e8277f 100644 --- a/Documentation/kprobes.txt +++ b/Documentation/kprobes.txt @@ -411,7 +411,8 @@ int init_module(void) printk("Couldn't find %s to plant kprobe\n", "do_fork"); return -1; } - if ((ret = register_kprobe(&kp) < 0)) { + ret = register_kprobe(&kp); + if (ret < 0) { printk("register_kprobe failed, returned %d\n", ret); return -1; } diff --git a/Documentation/locks.txt b/Documentation/locks.txt index ce1be79edfb8e0..e3b402ef33bd9f 100644 --- a/Documentation/locks.txt +++ b/Documentation/locks.txt @@ -65,20 +65,3 @@ The default is to disallow mandatory locking. The intention is that mandatory locking only be enabled on a local filesystem as the specific need arises. -Until an updated version of mount(8) becomes available you may have to apply -this patch to the mount sources (based on the version distributed with Rick -Faith's util-linux-2.5 package): - -*** mount.c.orig Sat Jun 8 09:14:31 1996 ---- mount.c Sat Jun 8 09:13:02 1996 -*************** -*** 100,105 **** ---- 100,107 ---- - { "noauto", 0, MS_NOAUTO }, /* Can only be mounted explicitly */ - { "user", 0, MS_USER }, /* Allow ordinary user to mount */ - { "nouser", 1, MS_USER }, /* Forbid ordinary user to mount */ -+ { "mand", 0, MS_MANDLOCK }, /* Allow mandatory locks on this FS */ -+ { "nomand", 1, MS_MANDLOCK }, /* Forbid mandatory locks on this FS */ - /* add new options here */ - #ifdef MS_NOSUB - { "sub", 1, MS_NOSUB }, /* allow submounts */ diff --git a/Documentation/md.txt b/Documentation/md.txt index 23e6cce40f9c98..03a13c462cf20e 100644 --- a/Documentation/md.txt +++ b/Documentation/md.txt @@ -51,6 +51,30 @@ superblock can be autodetected and run at boot time. The kernel parameter "raid=partitionable" (or "raid=part") means that all auto-detected arrays are assembled as partitionable. +Boot time assembly of degraded/dirty arrays +------------------------------------------- + +If a raid5 or raid6 array is both dirty and degraded, it could have +undetectable data corruption. This is because the fact that it is +'dirty' means that the parity cannot be trusted, and the fact that it +is degraded means that some datablocks are missing and cannot reliably +be reconstructed (due to no parity). + +For this reason, md will normally refuse to start such an array. This +requires the sysadmin to take action to explicitly start the array +desipite possible corruption. This is normally done with + mdadm --assemble --force .... + +This option is not really available if the array has the root +filesystem on it. In order to support this booting from such an +array, md supports a module parameter "start_dirty_degraded" which, +when set to 1, bypassed the checks and will allows dirty degraded +arrays to be started. + +So, to boot with a root filesystem of a dirty degraded raid[56], use + + md-mod.start_dirty_degraded=1 + Superblock formats ------------------ @@ -141,6 +165,70 @@ All md devices contain: in a fully functional array. If this is not yet known, the file will be empty. If an array is being resized (not currently possible) this will contain the larger of the old and new sizes. + Some raid level (RAID1) allow this value to be set while the + array is active. This will reconfigure the array. Otherwise + it can only be set while assembling an array. + + chunk_size + This is the size if bytes for 'chunks' and is only relevant to + raid levels that involve striping (1,4,5,6,10). The address space + of the array is conceptually divided into chunks and consecutive + chunks are striped onto neighbouring devices. + The size should be atleast PAGE_SIZE (4k) and should be a power + of 2. This can only be set while assembling an array + + component_size + For arrays with data redundancy (i.e. not raid0, linear, faulty, + multipath), all components must be the same size - or at least + there must a size that they all provide space for. This is a key + part or the geometry of the array. It is measured in sectors + and can be read from here. Writing to this value may resize + the array if the personality supports it (raid1, raid5, raid6), + and if the component drives are large enough. + + metadata_version + This indicates the format that is being used to record metadata + about the array. It can be 0.90 (traditional format), 1.0, 1.1, + 1.2 (newer format in varying locations) or "none" indicating that + the kernel isn't managing metadata at all. + + level + The raid 'level' for this array. The name will often (but not + always) be the same as the name of the module that implements the + level. To be auto-loaded the module must have an alias + md-$LEVEL e.g. md-raid5 + This can be written only while the array is being assembled, not + after it is started. + + new_dev + This file can be written but not read. The value written should + be a block device number as major:minor. e.g. 8:0 + This will cause that device to be attached to the array, if it is + available. It will then appear at md/dev-XXX (depending on the + name of the device) and further configuration is then possible. + + sync_speed_min + sync_speed_max + This are similar to /proc/sys/dev/raid/speed_limit_{min,max} + however they only apply to the particular array. + If no value has been written to these, of if the word 'system' + is written, then the system-wide value is used. If a value, + in kibibytes-per-second is written, then it is used. + When the files are read, they show the currently active value + followed by "(local)" or "(system)" depending on whether it is + a locally set or system-wide value. + + sync_completed + This shows the number of sectors that have been completed of + whatever the current sync_action is, followed by the number of + sectors in total that could need to be processed. The two + numbers are separated by a '/' thus effectively showing one + value, a fraction of the process that is complete. + + sync_speed + This shows the current actual speed, in K/sec, of the current + sync_action. It is averaged over the last 30 seconds. + As component devices are added to an md array, they appear in the 'md' directory as new directories named @@ -167,6 +255,38 @@ Each directory contains: of being recoverred to This list make grow in future. + errors + An approximate count of read errors that have been detected on + this device but have not caused the device to be evicted from + the array (either because they were corrected or because they + happened while the array was read-only). When using version-1 + metadata, this value persists across restarts of the array. + + This value can be written while assembling an array thus + providing an ongoing count for arrays with metadata managed by + userspace. + + slot + This gives the role that the device has in the array. It will + either be 'none' if the device is not active in the array + (i.e. is a spare or has failed) or an integer less than the + 'raid_disks' number for the array indicating which possition + it currently fills. This can only be set while assembling an + array. A device for which this is set is assumed to be working. + + offset + This gives the location in the device (in sectors from the + start) where data from the array will be stored. Any part of + the device before this offset us not touched, unless it is + used for storing metadata (Formats 1.1 and 1.2). + + size + The amount of the device, after the offset, that can be used + for storage of data. This will normally be the same as the + component_size. This can be written while assembling an + array. If a value less than the current component_size is + written, component_size will be reduced to this value. + An active md device will also contain and entry for each active device in the array. These are named diff --git a/Documentation/mutex-design.txt b/Documentation/mutex-design.txt new file mode 100644 index 00000000000000..cbf79881a41c8d --- /dev/null +++ b/Documentation/mutex-design.txt @@ -0,0 +1,135 @@ +Generic Mutex Subsystem + +started by Ingo Molnar <mingo@redhat.com> + + "Why on earth do we need a new mutex subsystem, and what's wrong + with semaphores?" + +firstly, there's nothing wrong with semaphores. But if the simpler +mutex semantics are sufficient for your code, then there are a couple +of advantages of mutexes: + + - 'struct mutex' is smaller on most architectures: .e.g on x86, + 'struct semaphore' is 20 bytes, 'struct mutex' is 16 bytes. + A smaller structure size means less RAM footprint, and better + CPU-cache utilization. + + - tighter code. On x86 i get the following .text sizes when + switching all mutex-alike semaphores in the kernel to the mutex + subsystem: + + text data bss dec hex filename + 3280380 868188 396860 4545428 455b94 vmlinux-semaphore + 3255329 865296 396732 4517357 44eded vmlinux-mutex + + that's 25051 bytes of code saved, or a 0.76% win - off the hottest + codepaths of the kernel. (The .data savings are 2892 bytes, or 0.33%) + Smaller code means better icache footprint, which is one of the + major optimization goals in the Linux kernel currently. + + - the mutex subsystem is slightly faster and has better scalability for + contended workloads. On an 8-way x86 system, running a mutex-based + kernel and testing creat+unlink+close (of separate, per-task files) + in /tmp with 16 parallel tasks, the average number of ops/sec is: + + Semaphores: Mutexes: + + $ ./test-mutex V 16 10 $ ./test-mutex V 16 10 + 8 CPUs, running 16 tasks. 8 CPUs, running 16 tasks. + checking VFS performance. checking VFS performance. + avg loops/sec: 34713 avg loops/sec: 84153 + CPU utilization: 63% CPU utilization: 22% + + i.e. in this workload, the mutex based kernel was 2.4 times faster + than the semaphore based kernel, _and_ it also had 2.8 times less CPU + utilization. (In terms of 'ops per CPU cycle', the semaphore kernel + performed 551 ops/sec per 1% of CPU time used, while the mutex kernel + performed 3825 ops/sec per 1% of CPU time used - it was 6.9 times + more efficient.) + + the scalability difference is visible even on a 2-way P4 HT box: + + Semaphores: Mutexes: + + $ ./test-mutex V 16 10 $ ./test-mutex V 16 10 + 4 CPUs, running 16 tasks. 8 CPUs, running 16 tasks. + checking VFS performance. checking VFS performance. + avg loops/sec: 127659 avg loops/sec: 181082 + CPU utilization: 100% CPU utilization: 34% + + (the straight performance advantage of mutexes is 41%, the per-cycle + efficiency of mutexes is 4.1 times better.) + + - there are no fastpath tradeoffs, the mutex fastpath is just as tight + as the semaphore fastpath. On x86, the locking fastpath is 2 + instructions: + + c0377ccb <mutex_lock>: + c0377ccb: f0 ff 08 lock decl (%eax) + c0377cce: 78 0e js c0377cde <.text.lock.mutex> + c0377cd0: c3 ret + + the unlocking fastpath is equally tight: + + c0377cd1 <mutex_unlock>: + c0377cd1: f0 ff 00 lock incl (%eax) + c0377cd4: 7e 0f jle c0377ce5 <.text.lock.mutex+0x7> + c0377cd6: c3 ret + + - 'struct mutex' semantics are well-defined and are enforced if + CONFIG_DEBUG_MUTEXES is turned on. Semaphores on the other hand have + virtually no debugging code or instrumentation. The mutex subsystem + checks and enforces the following rules: + + * - only one task can hold the mutex at a time + * - only the owner can unlock the mutex + * - multiple unlocks are not permitted + * - recursive locking is not permitted + * - a mutex object must be initialized via the API + * - a mutex object must not be initialized via memset or copying + * - task may not exit with mutex held + * - memory areas where held locks reside must not be freed + * - held mutexes must not be reinitialized + * - mutexes may not be used in irq contexts + + furthermore, there are also convenience features in the debugging + code: + + * - uses symbolic names of mutexes, whenever they are printed in debug output + * - point-of-acquire tracking, symbolic lookup of function names + * - list of all locks held in the system, printout of them + * - owner tracking + * - detects self-recursing locks and prints out all relevant info + * - detects multi-task circular deadlocks and prints out all affected + * locks and tasks (and only those tasks) + +Disadvantages +------------- + +The stricter mutex API means you cannot use mutexes the same way you +can use semaphores: e.g. they cannot be used from an interrupt context, +nor can they be unlocked from a different context that which acquired +it. [ I'm not aware of any other (e.g. performance) disadvantages from +using mutexes at the moment, please let me know if you find any. ] + +Implementation of mutexes +------------------------- + +'struct mutex' is the new mutex type, defined in include/linux/mutex.h +and implemented in kernel/mutex.c. It is a counter-based mutex with a +spinlock and a wait-list. The counter has 3 states: 1 for "unlocked", +0 for "locked" and negative numbers (usually -1) for "locked, potential +waiters queued". + +the APIs of 'struct mutex' have been streamlined: + + DEFINE_MUTEX(name); + + mutex_init(mutex); + + void mutex_lock(struct mutex *lock); + int mutex_lock_interruptible(struct mutex *lock); + int mutex_trylock(struct mutex *lock); + void mutex_unlock(struct mutex *lock); + int mutex_is_locked(struct mutex *lock); + diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index b0fe41da007bf8..8d8b4e5ea184a2 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt @@ -945,7 +945,6 @@ bond0 Link encap:Ethernet HWaddr 00:C0:F0:1F:37:B4 collisions:0 txqueuelen:0 eth0 Link encap:Ethernet HWaddr 00:C0:F0:1F:37:B4 - inet addr:XXX.XXX.XXX.YYY Bcast:XXX.XXX.XXX.255 Mask:255.255.252.0 UP BROADCAST RUNNING SLAVE MULTICAST MTU:1500 Metric:1 RX packets:3573025 errors:0 dropped:0 overruns:0 frame:0 TX packets:1643167 errors:1 dropped:0 overruns:1 carrier:0 @@ -953,7 +952,6 @@ eth0 Link encap:Ethernet HWaddr 00:C0:F0:1F:37:B4 Interrupt:10 Base address:0x1080 eth1 Link encap:Ethernet HWaddr 00:C0:F0:1F:37:B4 - inet addr:XXX.XXX.XXX.YYY Bcast:XXX.XXX.XXX.255 Mask:255.255.252.0 UP BROADCAST RUNNING SLAVE MULTICAST MTU:1500 Metric:1 RX packets:3651769 errors:0 dropped:0 overruns:0 frame:0 TX packets:1643480 errors:0 dropped:0 overruns:0 carrier:0 diff --git a/Documentation/networking/sk98lin.txt b/Documentation/networking/sk98lin.txt index 851fc97bb22f26..f9d979ee95268e 100644 --- a/Documentation/networking/sk98lin.txt +++ b/Documentation/networking/sk98lin.txt @@ -245,7 +245,7 @@ Default: Both This parameters is only relevant if auto-negotiation for this port is not set to "Sense". If auto-negotiation is set to "On", all three values are possible. If it is set to "Off", only "Full" and "Half" are allowed. -This parameter is usefull if your link partner does not support all +This parameter is useful if your link partner does not support all possible combinations. Flow Control diff --git a/Documentation/pci-error-recovery.txt b/Documentation/pci-error-recovery.txt new file mode 100644 index 00000000000000..d089967e4948b7 --- /dev/null +++ b/Documentation/pci-error-recovery.txt @@ -0,0 +1,246 @@ + + PCI Error Recovery + ------------------ + May 31, 2005 + + Current document maintainer: + Linas Vepstas <linas@austin.ibm.com> + + +Some PCI bus controllers are able to detect certain "hard" PCI errors +on the bus, such as parity errors on the data and address busses, as +well as SERR and PERR errors. These chipsets are then able to disable +I/O to/from the affected device, so that, for example, a bad DMA +address doesn't end up corrupting system memory. These same chipsets +are also able to reset the affected PCI device, and return it to +working condition. This document describes a generic API form +performing error recovery. + +The core idea is that after a PCI error has been detected, there must +be a way for the kernel to coordinate with all affected device drivers +so that the pci card can be made operational again, possibly after +performing a full electrical #RST of the PCI card. The API below +provides a generic API for device drivers to be notified of PCI +errors, and to be notified of, and respond to, a reset sequence. + +Preliminary sketch of API, cut-n-pasted-n-modified email from +Ben Herrenschmidt, circa 5 april 2005 + +The error recovery API support is exposed to the driver in the form of +a structure of function pointers pointed to by a new field in struct +pci_driver. The absence of this pointer in pci_driver denotes an +"non-aware" driver, behaviour on these is platform dependant. +Platforms like ppc64 can try to simulate pci hotplug remove/add. + +The definition of "pci_error_token" is not covered here. It is based on +Seto's work on the synchronous error detection. We still need to define +functions for extracting infos out of an opaque error token. This is +separate from this API. + +This structure has the form: + +struct pci_error_handlers +{ + int (*error_detected)(struct pci_dev *dev, pci_error_token error); + int (*mmio_enabled)(struct pci_dev *dev); + int (*resume)(struct pci_dev *dev); + int (*link_reset)(struct pci_dev *dev); + int (*slot_reset)(struct pci_dev *dev); +}; + +A driver doesn't have to implement all of these callbacks. The +only mandatory one is error_detected(). If a callback is not +implemented, the corresponding feature is considered unsupported. +For example, if mmio_enabled() and resume() aren't there, then the +driver is assumed as not doing any direct recovery and requires +a reset. If link_reset() is not implemented, the card is assumed as +not caring about link resets, in which case, if recover is supported, +the core can try recover (but not slot_reset() unless it really did +reset the slot). If slot_reset() is not supported, link_reset() can +be called instead on a slot reset. + +At first, the call will always be : + + 1) error_detected() + + Error detected. This is sent once after an error has been detected. At +this point, the device might not be accessible anymore depending on the +platform (the slot will be isolated on ppc64). The driver may already +have "noticed" the error because of a failing IO, but this is the proper +"synchronisation point", that is, it gives a chance to the driver to +cleanup, waiting for pending stuff (timers, whatever, etc...) to +complete; it can take semaphores, schedule, etc... everything but touch +the device. Within this function and after it returns, the driver +shouldn't do any new IOs. Called in task context. This is sort of a +"quiesce" point. See note about interrupts at the end of this doc. + + Result codes: + - PCIERR_RESULT_CAN_RECOVER: + Driever returns this if it thinks it might be able to recover + the HW by just banging IOs or if it wants to be given + a chance to extract some diagnostic informations (see + below). + - PCIERR_RESULT_NEED_RESET: + Driver returns this if it thinks it can't recover unless the + slot is reset. + - PCIERR_RESULT_DISCONNECT: + Return this if driver thinks it won't recover at all, + (this will detach the driver ? or just leave it + dangling ? to be decided) + +So at this point, we have called error_detected() for all drivers +on the segment that had the error. On ppc64, the slot is isolated. What +happens now typically depends on the result from the drivers. If all +drivers on the segment/slot return PCIERR_RESULT_CAN_RECOVER, we would +re-enable IOs on the slot (or do nothing special if the platform doesn't +isolate slots) and call 2). If not and we can reset slots, we go to 4), +if neither, we have a dead slot. If it's an hotplug slot, we might +"simulate" reset by triggering HW unplug/replug though. + +>>> Current ppc64 implementation assumes that a device driver will +>>> *not* schedule or semaphore in this routine; the current ppc64 +>>> implementation uses one kernel thread to notify all devices; +>>> thus, of one device sleeps/schedules, all devices are affected. +>>> Doing better requires complex multi-threaded logic in the error +>>> recovery implementation (e.g. waiting for all notification threads +>>> to "join" before proceeding with recovery.) This seems excessively +>>> complex and not worth implementing. + +>>> The current ppc64 implementation doesn't much care if the device +>>> attempts i/o at this point, or not. I/O's will fail, returning +>>> a value of 0xff on read, and writes will be dropped. If the device +>>> driver attempts more than 10K I/O's to a frozen adapter, it will +>>> assume that the device driver has gone into an infinite loop, and +>>> it will panic the the kernel. + + 2) mmio_enabled() + + This is the "early recovery" call. IOs are allowed again, but DMA is +not (hrm... to be discussed, I prefer not), with some restrictions. This +is NOT a callback for the driver to start operations again, only to +peek/poke at the device, extract diagnostic information, if any, and +eventually do things like trigger a device local reset or some such, +but not restart operations. This is sent if all drivers on a segment +agree that they can try to recover and no automatic link reset was +performed by the HW. If the platform can't just re-enable IOs without +a slot reset or a link reset, it doesn't call this callback and goes +directly to 3) or 4). All IOs should be done _synchronously_ from +within this callback, errors triggered by them will be returned via +the normal pci_check_whatever() api, no new error_detected() callback +will be issued due to an error happening here. However, such an error +might cause IOs to be re-blocked for the whole segment, and thus +invalidate the recovery that other devices on the same segment might +have done, forcing the whole segment into one of the next states, +that is link reset or slot reset. + + Result codes: + - PCIERR_RESULT_RECOVERED + Driver returns this if it thinks the device is fully + functionnal and thinks it is ready to start + normal driver operations again. There is no + guarantee that the driver will actually be + allowed to proceed, as another driver on the + same segment might have failed and thus triggered a + slot reset on platforms that support it. + + - PCIERR_RESULT_NEED_RESET + Driver returns this if it thinks the device is not + recoverable in it's current state and it needs a slot + reset to proceed. + + - PCIERR_RESULT_DISCONNECT + Same as above. Total failure, no recovery even after + reset driver dead. (To be defined more precisely) + +>>> The current ppc64 implementation does not implement this callback. + + 3) link_reset() + + This is called after the link has been reset. This is typically +a PCI Express specific state at this point and is done whenever a +non-fatal error has been detected that can be "solved" by resetting +the link. This call informs the driver of the reset and the driver +should check if the device appears to be in working condition. +This function acts a bit like 2) mmio_enabled(), in that the driver +is not supposed to restart normal driver I/O operations right away. +Instead, it should just "probe" the device to check it's recoverability +status. If all is right, then the core will call resume() once all +drivers have ack'd link_reset(). + + Result codes: + (identical to mmio_enabled) + +>>> The current ppc64 implementation does not implement this callback. + + 4) slot_reset() + + This is called after the slot has been soft or hard reset by the +platform. A soft reset consists of asserting the adapter #RST line +and then restoring the PCI BARs and PCI configuration header. If the +platform supports PCI hotplug, then it might instead perform a hard +reset by toggling power on the slot off/on. This call gives drivers +the chance to re-initialize the hardware (re-download firmware, etc.), +but drivers shouldn't restart normal I/O processing operations at +this point. (See note about interrupts; interrupts aren't guaranteed +to be delivered until the resume() callback has been called). If all +device drivers report success on this callback, the patform will call +resume() to complete the error handling and let the driver restart +normal I/O processing. + +A driver can still return a critical failure for this function if +it can't get the device operational after reset. If the platform +previously tried a soft reset, it migh now try a hard reset (power +cycle) and then call slot_reset() again. It the device still can't +be recovered, there is nothing more that can be done; the platform +will typically report a "permanent failure" in such a case. The +device will be considered "dead" in this case. + + Result codes: + - PCIERR_RESULT_DISCONNECT + Same as above. + +>>> The current ppc64 implementation does not try a power-cycle reset +>>> if the driver returned PCIERR_RESULT_DISCONNECT. However, it should. + + 5) resume() + + This is called if all drivers on the segment have returned +PCIERR_RESULT_RECOVERED from one of the 3 prevous callbacks. +That basically tells the driver to restart activity, tht everything +is back and running. No result code is taken into account here. If +a new error happens, it will restart a new error handling process. + +That's it. I think this covers all the possibilities. The way those +callbacks are called is platform policy. A platform with no slot reset +capability for example may want to just "ignore" drivers that can't +recover (disconnect them) and try to let other cards on the same segment +recover. Keep in mind that in most real life cases, though, there will +be only one driver per segment. + +Now, there is a note about interrupts. If you get an interrupt and your +device is dead or has been isolated, there is a problem :) + +After much thinking, I decided to leave that to the platform. That is, +the recovery API only precies that: + + - There is no guarantee that interrupt delivery can proceed from any +device on the segment starting from the error detection and until the +restart callback is sent, at which point interrupts are expected to be +fully operational. + + - There is no guarantee that interrupt delivery is stopped, that is, ad +river that gets an interrupts after detecting an error, or that detects +and error within the interrupt handler such that it prevents proper +ack'ing of the interrupt (and thus removal of the source) should just +return IRQ_NOTHANDLED. It's up to the platform to deal with taht +condition, typically by masking the irq source during the duration of +the error handling. It is expected that the platform "knows" which +interrupts are routed to error-management capable slots and can deal +with temporarily disabling that irq number during error processing (this +isn't terribly complex). That means some IRQ latency for other devices +sharing the interrupt, but there is simply no other way. High end +platforms aren't supposed to share interrupts between many devices +anyway :) + + +Revised: 31 May 2005 Linas Vepstas <linas@austin.ibm.com> diff --git a/Documentation/pm.txt b/Documentation/pm.txt index 2ea1149bf6b044..79c0f32a760e98 100644 --- a/Documentation/pm.txt +++ b/Documentation/pm.txt @@ -218,7 +218,7 @@ proceed in the opposite direction. Q: Who do I contact for additional information about enabling power management for my specific driver/device? -ACPI Development mailing list: acpi-devel@lists.sourceforge.net +ACPI Development mailing list: linux-acpi@vger.kernel.org System Interface -- OBSOLETE, DO NOT USE! ----------------************************* diff --git a/Documentation/power/interface.txt b/Documentation/power/interface.txt index f5ebda5f4276ad..bd4ffb5bd49a1d 100644 --- a/Documentation/power/interface.txt +++ b/Documentation/power/interface.txt @@ -41,3 +41,14 @@ to. Writing to this file will accept one of It will only change to 'firmware' or 'platform' if the system supports it. +/sys/power/image_size controls the size of the image created by +the suspend-to-disk mechanism. It can be written a string +representing a non-negative integer that will be used as an upper +limit of the image size, in megabytes. The suspend-to-disk mechanism will +do its best to ensure the image size will not exceed that number. However, +if this turns out to be impossible, it will try to suspend anyway using the +smallest image possible. In particular, if "0" is written to this file, the +suspend image will be as small as possible. + +Reading from this file will display the current image size limit, which +is set to 500 MB by default. diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index b0d50840788ebf..08c79d4dc54036 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt @@ -27,6 +27,11 @@ echo shutdown > /sys/power/disk; echo disk > /sys/power/state echo platform > /sys/power/disk; echo disk > /sys/power/state +If you want to limit the suspend image size to N megabytes, do + +echo N > /sys/power/image_size + +before suspend (it is limited to 500 MB by default). Encrypted suspend image: ------------------------ @@ -207,7 +212,7 @@ A: Try running cat `cat /proc/[0-9]*/maps | grep / | sed 's:.* /:/:' | sort -u` > /dev/null -after resume. swapoff -a; swapon -a may also be usefull. +after resume. swapoff -a; swapon -a may also be useful. Q: What happens to devices during swsusp? They seem to be resumed during system suspend? @@ -318,7 +323,7 @@ to be useless to try to suspend to disk while that app is running? A: No, it should work okay, as long as your app does not mlock() it. Just prepare big enough swap partition. -Q: What information is usefull for debugging suspend-to-disk problems? +Q: What information is useful for debugging suspend-to-disk problems? A: Well, last messages on the screen are always useful. If something is broken, it is usually some kernel driver, therefore trying with as diff --git a/Documentation/powerpc/00-INDEX b/Documentation/powerpc/00-INDEX index e7bea0a407b4d5..d6d65b9bcfe325 100644 --- a/Documentation/powerpc/00-INDEX +++ b/Documentation/powerpc/00-INDEX @@ -8,12 +8,18 @@ please mail me. cpu_features.txt - info on how we support a variety of CPUs with minimal compile-time options. +eeh-pci-error-recovery.txt + - info on PCI Bus EEH Error Recovery +hvcs.txt + - IBM "Hypervisor Virtual Console Server" Installation Guide +mpc52xx.txt + - Linux 2.6.x on MPC52xx family ppc_htab.txt - info about the Linux/PPC /proc/ppc_htab entry -smp.txt - - use and state info about Linux/PPC on MP machines SBC8260_memory_mapping.txt - EST SBC8260 board info +smp.txt + - use and state info about Linux/PPC on MP machines sound.txt - info on sound support under Linux/PPC zImage_layout.txt diff --git a/Documentation/stable_kernel_rules.txt b/Documentation/stable_kernel_rules.txt index 2c81305090dffa..e409e5d0748601 100644 --- a/Documentation/stable_kernel_rules.txt +++ b/Documentation/stable_kernel_rules.txt @@ -1,58 +1,56 @@ Everything you ever wanted to know about Linux 2.6 -stable releases. -Rules on what kind of patches are accepted, and what ones are not, into -the "-stable" tree: +Rules on what kind of patches are accepted, and which ones are not, into the +"-stable" tree: - It must be obviously correct and tested. - - It can not bigger than 100 lines, with context. + - It can not be bigger than 100 lines, with context. - It must fix only one thing. - It must fix a real bug that bothers people (not a, "This could be a - problem..." type thing.) + problem..." type thing). - It must fix a problem that causes a build error (but not for things marked CONFIG_BROKEN), an oops, a hang, data corruption, a real - security issue, or some "oh, that's not good" issue. In short, - something critical. - - No "theoretical race condition" issues, unless an explanation of how - the race can be exploited. + security issue, or some "oh, that's not good" issue. In short, something + critical. + - No "theoretical race condition" issues, unless an explanation of how the + race can be exploited is also provided. - It can not contain any "trivial" fixes in it (spelling changes, - whitespace cleanups, etc.) + whitespace cleanups, etc). - It must be accepted by the relevant subsystem maintainer. - - It must follow Documentation/SubmittingPatches rules. + - It must follow the Documentation/SubmittingPatches rules. Procedure for submitting patches to the -stable tree: - Send the patch, after verifying that it follows the above rules, to stable@kernel.org. - - The sender will receive an ack when the patch has been accepted into - the queue, or a nak if the patch is rejected. This response might - take a few days, according to the developer's schedules. - - If accepted, the patch will be added to the -stable queue, for review - by other developers. + - The sender will receive an ACK when the patch has been accepted into the + queue, or a NAK if the patch is rejected. This response might take a few + days, according to the developer's schedules. + - If accepted, the patch will be added to the -stable queue, for review by + other developers. - Security patches should not be sent to this alias, but instead to the - documented security@kernel.org. + documented security@kernel.org address. Review cycle: - - When the -stable maintainers decide for a review cycle, the patches - will be sent to the review committee, and the maintainer of the - affected area of the patch (unless the submitter is the maintainer of - the area) and CC: to the linux-kernel mailing list. - - The review committee has 48 hours in which to ack or nak the patch. + - When the -stable maintainers decide for a review cycle, the patches will be + sent to the review committee, and the maintainer of the affected area of + the patch (unless the submitter is the maintainer of the area) and CC: to + the linux-kernel mailing list. + - The review committee has 48 hours in which to ACK or NAK the patch. - If the patch is rejected by a member of the committee, or linux-kernel - members object to the patch, bringing up issues that the maintainers - and members did not realize, the patch will be dropped from the - queue. - - At the end of the review cycle, the acked patches will be added to - the latest -stable release, and a new -stable release will happen. - - Security patches will be accepted into the -stable tree directly from - the security kernel team, and not go through the normal review cycle. + members object to the patch, bringing up issues that the maintainers and + members did not realize, the patch will be dropped from the queue. + - At the end of the review cycle, the ACKed patches will be added to the + latest -stable release, and a new -stable release will happen. + - Security patches will be accepted into the -stable tree directly from the + security kernel team, and not go through the normal review cycle. Contact the kernel security team for more details on this procedure. Review committe: - - This will be made up of a number of kernel developers who have - volunteered for this task, and a few that haven't. - + - This is made up of a number of kernel developers who have volunteered for + this task, and a few that haven't. diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 2f1aae32a5d9df..6910c0136f8d7e 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -26,12 +26,13 @@ Currently, these files are in /proc/sys/vm: - min_free_kbytes - laptop_mode - block_dump +- drop-caches ============================================================== dirty_ratio, dirty_background_ratio, dirty_expire_centisecs, dirty_writeback_centisecs, vfs_cache_pressure, laptop_mode, -block_dump, swap_token_timeout: +block_dump, swap_token_timeout, drop-caches: See Documentation/filesystems/proc.txt @@ -102,3 +103,20 @@ This is used to force the Linux VM to keep a minimum number of kilobytes free. The VM uses this number to compute a pages_min value for each lowmem zone in the system. Each lowmem zone gets a number of reserved free pages based proportionally on its size. + +============================================================== + +percpu_pagelist_fraction + +This is the fraction of pages at most (high mark pcp->high) in each zone that +are allocated for each per cpu page list. The min value for this is 8. It +means that we don't allow more than 1/8th of pages in each zone to be +allocated in any single per_cpu_pagelist. This entry only changes the value +of hot per cpu pagelists. User can specify a number like 100 to allocate +1/100th of each zone to each per cpu page list. + +The batch value of each per cpu pagelist is also updated as a result. It is +set to pcp->high/4. The upper limit of batch is (PAGE_SHIFT * 8) + +The initial value is zero. Kernel does not use this value at boot time to set +the high water marks for each per cpu page list. diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index 330246ac80f80f..74fb085e178b9d 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv @@ -141,3 +141,4 @@ 140 -> Osprey 440 [0070:ff07] 141 -> Asound Skyeye PCTV 142 -> Sabrent TV-FM (bttv version) +143 -> Hauppauge ImpactVCB (bt878) [0070:13eb] diff --git a/Documentation/video4linux/CARDLIST.cx88 b/Documentation/video4linux/CARDLIST.cx88 index a1017d1a85d4b8..34b6e59f296824 100644 --- a/Documentation/video4linux/CARDLIST.cx88 +++ b/Documentation/video4linux/CARDLIST.cx88 @@ -16,7 +16,7 @@ 15 -> DViCO FusionHDTV DVB-T1 [18ac:db00] 16 -> KWorld LTV883RF 17 -> DViCO FusionHDTV 3 Gold-Q [18ac:d810] - 18 -> Hauppauge Nova-T DVB-T [0070:9002] + 18 -> Hauppauge Nova-T DVB-T [0070:9002,0070:9001] 19 -> Conexant DVB-T reference design [14f1:0187] 20 -> Provideo PV259 [1540:2580] 21 -> DViCO FusionHDTV DVB-T Plus [18ac:db10] @@ -35,3 +35,11 @@ 34 -> ATI HDTV Wonder [1002:a101] 35 -> WinFast DTV1000-T [107d:665f] 36 -> AVerTV 303 (M126) [1461:000a] + 37 -> Hauppauge Nova-S-Plus DVB-S [0070:9201,0070:9202] + 38 -> Hauppauge Nova-SE2 DVB-S [0070:9200] + 39 -> KWorld DVB-S 100 [17de:08b2] + 40 -> Hauppauge WinTV-HVR1100 DVB-T/Hybrid [0070:9400,0070:9402] + 41 -> Hauppauge WinTV-HVR1100 DVB-T/Hybrid (Low Profile) [0070:9800,0070:9802] + 42 -> digitalnow DNTV Live! DVB-T Pro [1822:0025] + 43 -> KWorld/VStream XPert DVB-T with cx22702 [17de:08a1] + 44 -> DViCO FusionHDTV DVB-T Dual Digital [18ac:db50] diff --git a/Documentation/video4linux/CARDLIST.saa7134 b/Documentation/video4linux/CARDLIST.saa7134 index efb708ec116ace..cb3a59bbeb172b 100644 --- a/Documentation/video4linux/CARDLIST.saa7134 +++ b/Documentation/video4linux/CARDLIST.saa7134 @@ -56,7 +56,7 @@ 55 -> LifeView FlyDVB-T DUO [5168:0502,5168:0306] 56 -> Avermedia AVerTV 307 [1461:a70a] 57 -> Avermedia AVerTV GO 007 FM [1461:f31f] - 58 -> ADS Tech Instant TV (saa7135) [1421:0350,1421:0370,1421:1370] + 58 -> ADS Tech Instant TV (saa7135) [1421:0350,1421:0351,1421:0370,1421:1370] 59 -> Kworld/Tevion V-Stream Xpert TV PVR7134 60 -> Typhoon DVB-T Duo Digital/Analog Cardbus [4e42:0502] 61 -> Philips TOUGH DVB-T reference design [1131:2004] @@ -81,4 +81,5 @@ 80 -> ASUS Digimatrix TV [1043:0210] 81 -> Philips Tiger reference design [1131:2018] 82 -> MSI TV@Anywhere plus [1462:6231] - + 83 -> Terratec Cinergy 250 PCI TV [153b:1160] + 84 -> LifeView FlyDVB Trio [5168:0319] diff --git a/Documentation/video4linux/CARDLIST.tuner b/Documentation/video4linux/CARDLIST.tuner index 9d6544ea9f4188..0bf3d5bf9ef8c2 100644 --- a/Documentation/video4linux/CARDLIST.tuner +++ b/Documentation/video4linux/CARDLIST.tuner @@ -40,7 +40,7 @@ tuner=38 - Philips PAL/SECAM multi (FM1216ME MK3) tuner=39 - LG NTSC (newer TAPC series) tuner=40 - HITACHI V7-J180AT tuner=41 - Philips PAL_MK (FI1216 MK) -tuner=42 - Philips 1236D ATSC/NTSC daul in +tuner=42 - Philips 1236D ATSC/NTSC dual in tuner=43 - Philips NTSC MK3 (FM1236MK3 or FM1236/F) tuner=44 - Philips 4 in 1 (ATI TV Wonder Pro/Conexant) tuner=45 - Microtune 4049 FM5 @@ -50,7 +50,7 @@ tuner=48 - Tenna TNF 8831 BGFF) tuner=49 - Microtune 4042 FI5 ATSC/NTSC dual in tuner=50 - TCL 2002N tuner=51 - Philips PAL/SECAM_D (FM 1256 I-H3) -tuner=52 - Thomson DDT 7610 (ATSC/NTSC) +tuner=52 - Thomson DTT 7610 (ATSC/NTSC) tuner=53 - Philips FQ1286 tuner=54 - tda8290+75 tuner=55 - TCL 2002MB @@ -58,7 +58,7 @@ tuner=56 - Philips PAL/SECAM multi (FQ1216AME MK4) tuner=57 - Philips FQ1236A MK4 tuner=58 - Ymec TVision TVF-8531MF/8831MF/8731MF tuner=59 - Ymec TVision TVF-5533MF -tuner=60 - Thomson DDT 7611 (ATSC/NTSC) +tuner=60 - Thomson DTT 761X (ATSC/NTSC) tuner=61 - Tena TNF9533-D/IF/TNF9533-B/DF tuner=62 - Philips TEA5767HN FM Radio tuner=63 - Philips FMD1216ME MK3 Hybrid Tuner |