€•¨g      Œsphinx.addnodes”Œdocument”“”)”}”(Œ	rawsource”Œ ”Œchildren”]”(Œtranslations”ŒLanguagesNode”“”)”}”(hhh]”(h Œpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ
attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ	refdomain”Œstd”Œreftype”Œdoc”Œ	reftarget”Œ)/translations/zh_CN/arch/x86/orc-unwinder”Œmodname”NŒ	classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ)/translations/zh_TW/arch/x86/orc-unwinder”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ)/translations/it_IT/arch/x86/orc-unwinder”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ)/translations/ja_JP/arch/x86/orc-unwinder”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ)/translations/ko_KR/arch/x86/orc-unwinder”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ)/translations/sp_SP/arch/x86/orc-unwinder”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h
hhŒ	_document”hŒsource”NŒline”NubhŒcomment”“”)”}”(hŒ SPDX-License-Identifier: GPL-2.0”h]”hŒ SPDX-License-Identifier: GPL-2.0”…””}”hh£sbah}”(h]”h ]”h"]”h$]”h&]”Œ	xml:space”Œpreserve”uh1h¡hhhžhhŸŒC/var/lib/git/docbuild/linux/Documentation/arch/x86/orc-unwinder.rst”h KubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒORC unwinder”h]”hŒORC unwinder”…””}”(hh»hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hh¶hžhhŸh³h Kubhµ)”}”(hhh]”(hº)”}”(hŒOverview”h]”hŒOverview”…””}”(hhÌhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hhÉhžhhŸh³h KubhŒ	paragraph”“”)”}”(hX  The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is
similar in concept to a DWARF unwinder.  The difference is that the
format of the ORC data is much simpler than DWARF, which in turn allows
the ORC unwinder to be much simpler and faster.”h]”hX  The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is
similar in concept to a DWARF unwinder.  The difference is that the
format of the ORC data is much simpler than DWARF, which in turn allows
the ORC unwinder to be much simpler and faster.”…””}”(hhÜhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K
hhÉhžhubhÛ)”}”(hXÙ  The ORC data consists of unwind tables which are generated by objtool.
They contain out-of-band data which is used by the in-kernel ORC
unwinder.  Objtool generates the ORC data by first doing compile-time
stack metadata validation (CONFIG_STACK_VALIDATION).  After analyzing
all the code paths of a .o file, it determines information about the
stack state at each instruction address in the file and outputs that
information to the .orc_unwind and .orc_unwind_ip sections.”h]”hXÙ  The ORC data consists of unwind tables which are generated by objtool.
They contain out-of-band data which is used by the in-kernel ORC
unwinder.  Objtool generates the ORC data by first doing compile-time
stack metadata validation (CONFIG_STACK_VALIDATION).  After analyzing
all the code paths of a .o file, it determines information about the
stack state at each instruction address in the file and outputs that
information to the .orc_unwind and .orc_unwind_ip sections.”…””}”(hhêhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h KhhÉhžhubhÛ)”}”(hŒÓThe per-object ORC sections are combined at link time and are sorted and
post-processed at boot time.  The unwinder uses the resulting data to
correlate instruction addresses with their stack states at run time.”h]”hŒÓThe per-object ORC sections are combined at link time and are sorted and
post-processed at boot time.  The unwinder uses the resulting data to
correlate instruction addresses with their stack states at run time.”…””}”(hhøhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h KhhÉhžhubeh}”(h]”Œoverview”ah ]”h"]”Œoverview”ah$]”h&]”uh1h´hh¶hžhhŸh³h Kubhµ)”}”(hhh]”(hº)”}”(hŒORC vs frame pointers”h]”hŒORC vs frame pointers”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hj  hžhhŸh³h KubhÛ)”}”(hX  With frame pointers enabled, GCC adds instrumentation code to every
function in the kernel.  The kernel's .text size increases by about
3.2%, resulting in a broad kernel-wide slowdown.  Measurements by Mel
Gorman [1]_ have shown a slowdown of 5-10% for some workloads.”h]”(hŒ×With frame pointers enabled, GCC adds instrumentation code to every
function in the kernel.  The kernelâ€™s .text size increases by about
3.2%, resulting in a broad kernel-wide slowdown.  Measurements by Mel
Gorman ”…””}”(hj  hžhhŸNh NubhŒfootnote_reference”“”)”}”(hŒ[1]_”h]”hŒ1”…””}”(hj)  hžhhŸNh Nubah}”(h]”Œid1”ah ]”h"]”h$]”h&]”Œrefid”Œid4”Œdocname”Œarch/x86/orc-unwinder”uh1j'  hj  Œresolved”KubhŒ3 have shown a slowdown of 5-10% for some workloads.”…””}”(hj  hžhhŸNh Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h Khj  hžhubhÛ)”}”(hX  In contrast, the ORC unwinder has no effect on text size or runtime
performance, because the debuginfo is out of band.  So if you disable
frame pointers and enable the ORC unwinder, you get a nice performance
improvement across the board, and still have reliable stack traces.”h]”hX  In contrast, the ORC unwinder has no effect on text size or runtime
performance, because the debuginfo is out of band.  So if you disable
frame pointers and enable the ORC unwinder, you get a nice performance
improvement across the board, and still have reliable stack traces.”…””}”(hjG  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K$hj  hžhubhÛ)”}”(hŒIngo Molnar says:”h]”hŒIngo Molnar says:”…””}”(hjU  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K)hj  hžhubhŒblock_quote”“”)”}”(hX(  "Note that it's not just a performance improvement, but also an
instruction cache locality improvement: 3.2% .text savings almost
directly transform into a similarly sized reduction in cache
footprint. That can transform to even higher speedups for workloads
whose cache locality is borderline."
”h]”hÛ)”}”(hX'  "Note that it's not just a performance improvement, but also an
instruction cache locality improvement: 3.2% .text savings almost
directly transform into a similarly sized reduction in cache
footprint. That can transform to even higher speedups for workloads
whose cache locality is borderline."”h]”hX-  â€œNote that itâ€™s not just a performance improvement, but also an
instruction cache locality improvement: 3.2% .text savings almost
directly transform into a similarly sized reduction in cache
footprint. That can transform to even higher speedups for workloads
whose cache locality is borderline.â€”…””}”(hji  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K+hje  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jc  hŸh³h K+hj  hžhubhÛ)”}”(hX   Another benefit of ORC compared to frame pointers is that it can
reliably unwind across interrupts and exceptions.  Frame pointer based
unwinds can sometimes skip the caller of the interrupted function, if it
was a leaf function or if the interrupt hit before the frame pointer was
saved.”h]”hX   Another benefit of ORC compared to frame pointers is that it can
reliably unwind across interrupts and exceptions.  Frame pointer based
unwinds can sometimes skip the caller of the interrupted function, if it
was a leaf function or if the interrupt hit before the frame pointer was
saved.”…””}”(hj}  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K1hj  hžhubhÛ)”}”(hŒ¯The main disadvantage of the ORC unwinder compared to frame pointers is
that it needs more memory to store the ORC unwind tables: roughly 2-4MB
depending on the kernel config.”h]”hŒ¯The main disadvantage of the ORC unwinder compared to frame pointers is
that it needs more memory to store the ORC unwind tables: roughly 2-4MB
depending on the kernel config.”…””}”(hj‹  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K7hj  hžhubeh}”(h]”Œorc-vs-frame-pointers”ah ]”h"]”Œorc vs frame pointers”ah$]”h&]”uh1h´hh¶hžhhŸh³h Kubhµ)”}”(hhh]”(hº)”}”(hŒORC vs DWARF”h]”hŒORC vs DWARF”…””}”(hj¤  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hj¡  hžhhŸh³h K=ubhÛ)”}”(hX5  ORC debuginfo's advantage over DWARF itself is that it's much simpler.
It gets rid of the complex DWARF CFI state machine and also gets rid of
the tracking of unnecessary registers.  This allows the unwinder to be
much simpler, meaning fewer bugs, which is especially important for
mission critical oops code.”h]”hX9  ORC debuginfoâ€™s advantage over DWARF itself is that itâ€™s much simpler.
It gets rid of the complex DWARF CFI state machine and also gets rid of
the tracking of unnecessary registers.  This allows the unwinder to be
much simpler, meaning fewer bugs, which is especially important for
mission critical oops code.”…””}”(hj²  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K?hj¡  hžhubhÛ)”}”(hX’  The simpler debuginfo format also enables the unwinder to be much faster
than DWARF, which is important for perf and lockdep.  In a basic
performance test by Jiri Slaby [2]_, the ORC unwinder was about 20x
faster than an out-of-tree DWARF unwinder.  (Note: That measurement was
taken before some performance tweaks were added, which doubled
performance, so the speedup over DWARF may be closer to 40x.)”h]”(hŒ©The simpler debuginfo format also enables the unwinder to be much faster
than DWARF, which is important for perf and lockdep.  In a basic
performance test by Jiri Slaby ”…””}”(hjÀ  hžhhŸNh Nubj(  )”}”(hŒ[2]_”h]”hŒ2”…””}”(hjÈ  hžhhŸNh Nubah}”(h]”Œid2”ah ]”h"]”h$]”h&]”j8  Œid5”j:  j;  uh1j'  hjÀ  j<  KubhŒå, the ORC unwinder was about 20x
faster than an out-of-tree DWARF unwinder.  (Note: That measurement was
taken before some performance tweaks were added, which doubled
performance, so the speedup over DWARF may be closer to 40x.)”…””}”(hjÀ  hžhhŸNh Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h KEhj¡  hžhubhÛ)”}”(hŒ¯The ORC data format does have a few downsides compared to DWARF.  ORC
unwind tables take up ~50% more RAM (+1.3MB on an x86 defconfig kernel)
than DWARF-based eh_frame tables.”h]”hŒ¯The ORC data format does have a few downsides compared to DWARF.  ORC
unwind tables take up ~50% more RAM (+1.3MB on an x86 defconfig kernel)
than DWARF-based eh_frame tables.”…””}”(hjâ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h KLhj¡  hžhubhÛ)”}”(hX2  Another potential downside is that, as GCC evolves, it's conceivable
that the ORC data may end up being *too* simple to describe the state of
the stack for certain optimizations.  But IMO this is unlikely because
GCC saves the frame pointer for any unusual stack adjustments it does,
so I suspect we'll really only ever need to keep track of the stack
pointer and the frame pointer between call frames.  But even if we do
end up having to track all the registers DWARF tracks, at least we will
still be able to control the format, e.g. no complex state machines.”h]”(hŒjAnother potential downside is that, as GCC evolves, itâ€™s conceivable
that the ORC data may end up being ”…””}”(hjð  hžhhŸNh NubhŒemphasis”“”)”}”(hŒ*too*”h]”hŒtoo”…””}”(hjú  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jø  hjð  ubhXÇ   simple to describe the state of
the stack for certain optimizations.  But IMO this is unlikely because
GCC saves the frame pointer for any unusual stack adjustments it does,
so I suspect weâ€™ll really only ever need to keep track of the stack
pointer and the frame pointer between call frames.  But even if we do
end up having to track all the registers DWARF tracks, at least we will
still be able to control the format, e.g. no complex state machines.”…””}”(hjð  hžhhŸNh Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h KPhj¡  hžhubeh}”(h]”Œorc-vs-dwarf”ah ]”h"]”Œorc vs dwarf”ah$]”h&]”uh1h´hh¶hžhhŸh³h K=ubhµ)”}”(hhh]”(hº)”}”(hŒORC unwind table generation”h]”hŒORC unwind table generation”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hj  hžhhŸh³h K[ubhÛ)”}”(hX;  The ORC data is generated by objtool.  With the existing compile-time
stack metadata validation feature, objtool already follows all code
paths, and so it already has all the information it needs to be able to
generate ORC data from scratch.  So it's an easy step to go from stack
validation to ORC data generation.”h]”hX=  The ORC data is generated by objtool.  With the existing compile-time
stack metadata validation feature, objtool already follows all code
paths, and so it already has all the information it needs to be able to
generate ORC data from scratch.  So itâ€™s an easy step to go from stack
validation to ORC data generation.”…””}”(hj+  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K]hj  hžhubhÛ)”}”(hŒûIt should be possible to instead generate the ORC data with a simple
tool which converts DWARF to ORC data.  However, such a solution would
be incomplete due to the kernel's extensive use of asm, inline asm, and
special sections like exception tables.”h]”hŒýIt should be possible to instead generate the ORC data with a simple
tool which converts DWARF to ORC data.  However, such a solution would
be incomplete due to the kernelâ€™s extensive use of asm, inline asm, and
special sections like exception tables.”…””}”(hj9  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h Kchj  hžhubhÛ)”}”(hX´  That could be rectified by manually annotating those special code paths
using GNU assembler .cfi annotations in .S files, and homegrown
annotations for inline asm in .c files.  But asm annotations were tried
in the past and were found to be unmaintainable.  They were often
incorrect/incomplete and made the code harder to read and keep updated.
And based on looking at glibc code, annotating inline asm in .c files
might be even worse.”h]”hX´  That could be rectified by manually annotating those special code paths
using GNU assembler .cfi annotations in .S files, and homegrown
annotations for inline asm in .c files.  But asm annotations were tried
in the past and were found to be unmaintainable.  They were often
incorrect/incomplete and made the code harder to read and keep updated.
And based on looking at glibc code, annotating inline asm in .c files
might be even worse.”…””}”(hjG  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h Khhj  hžhubhÛ)”}”(hŒúObjtool still needs a few annotations, but only in code which does
unusual things to the stack like entry code.  And even then, far fewer
annotations are needed than what DWARF would need, so they're much more
maintainable than DWARF CFI annotations.”h]”hŒüObjtool still needs a few annotations, but only in code which does
unusual things to the stack like entry code.  And even then, far fewer
annotations are needed than what DWARF would need, so theyâ€™re much more
maintainable than DWARF CFI annotations.”…””}”(hjU  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h Kphj  hžhubhÛ)”}”(hX;  So the advantages of using objtool to generate ORC data are that it
gives more accurate debuginfo, with very few annotations.  It also
insulates the kernel from toolchain bugs which can be very painful to
deal with in the kernel since we often have to workaround issues in
older versions of the toolchain for years.”h]”hX;  So the advantages of using objtool to generate ORC data are that it
gives more accurate debuginfo, with very few annotations.  It also
insulates the kernel from toolchain bugs which can be very painful to
deal with in the kernel since we often have to workaround issues in
older versions of the toolchain for years.”…””}”(hjc  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h Kuhj  hžhubhÛ)”}”(hXd  The downside is that the unwinder now becomes dependent on objtool's
ability to reverse engineer GCC code flow.  If GCC optimizations become
too complicated for objtool to follow, the ORC data generation might
stop working or become incomplete.  (It's worth noting that livepatch
already has such a dependency on objtool's ability to follow GCC code
flow.)”h]”hXj  The downside is that the unwinder now becomes dependent on objtoolâ€™s
ability to reverse engineer GCC code flow.  If GCC optimizations become
too complicated for objtool to follow, the ORC data generation might
stop working or become incomplete.  (Itâ€™s worth noting that livepatch
already has such a dependency on objtoolâ€™s ability to follow GCC code
flow.)”…””}”(hjq  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K{hj  hžhubhÛ)”}”(hX|  If newer versions of GCC come up with some optimizations which break
objtool, we may need to revisit the current implementation.  Some
possible solutions would be asking GCC to make the optimizations more
palatable, or having objtool use DWARF as an additional input, or
creating a GCC plugin to assist objtool with its analysis.  But for now,
objtool follows GCC code quite well.”h]”hX|  If newer versions of GCC come up with some optimizations which break
objtool, we may need to revisit the current implementation.  Some
possible solutions would be asking GCC to make the optimizations more
palatable, or having objtool use DWARF as an additional input, or
creating a GCC plugin to assist objtool with its analysis.  But for now,
objtool follows GCC code quite well.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K‚hj  hžhubeh}”(h]”Œorc-unwind-table-generation”ah ]”h"]”Œorc unwind table generation”ah$]”h&]”uh1h´hh¶hžhhŸh³h K[ubhµ)”}”(hhh]”(hº)”}”(hŒUnwinder implementation details”h]”hŒUnwinder implementation details”…””}”(hj˜  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hj•  hžhhŸh³h K‹ubhÛ)”}”(hX¥  Objtool generates the ORC data by integrating with the compile-time
stack metadata validation feature, which is described in detail in
tools/objtool/Documentation/objtool.txt.  After analyzing all
the code paths of a .o file, it creates an array of orc_entry structs,
and a parallel array of instruction addresses associated with those
structs, and writes them to the .orc_unwind and .orc_unwind_ip sections
respectively.”h]”hX¥  Objtool generates the ORC data by integrating with the compile-time
stack metadata validation feature, which is described in detail in
tools/objtool/Documentation/objtool.txt.  After analyzing all
the code paths of a .o file, it creates an array of orc_entry structs,
and a parallel array of instruction addresses associated with those
structs, and writes them to the .orc_unwind and .orc_unwind_ip sections
respectively.”…””}”(hj¦  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h Khj•  hžhubhÛ)”}”(hŒºThe ORC data is split into the two arrays for performance reasons, to
make the searchable part of the data (.orc_unwind_ip) more compact.  The
arrays are sorted in parallel at boot time.”h]”hŒºThe ORC data is split into the two arrays for performance reasons, to
make the searchable part of the data (.orc_unwind_ip) more compact.  The
arrays are sorted in parallel at boot time.”…””}”(hj´  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K•hj•  hžhubhÛ)”}”(hX  Performance is further improved by the use of a fast lookup table which
is created at runtime.  The fast lookup table associates a given address
with a range of indices for the .orc_unwind table, so that only a small
subset of the table needs to be searched.”h]”hX  Performance is further improved by the use of a fast lookup table which
is created at runtime.  The fast lookup table associates a given address
with a range of indices for the .orc_unwind table, so that only a small
subset of the table needs to be searched.”…””}”(hjÂ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K™hj•  hžhubeh}”(h]”Œunwinder-implementation-details”ah ]”h"]”Œunwinder implementation details”ah$]”h&]”uh1h´hh¶hžhhŸh³h K‹ubhµ)”}”(hhh]”(hº)”}”(hŒ	Etymology”h]”hŒ	Etymology”…””}”(hjÛ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hjØ  hžhhŸh³h K ubhÛ)”}”(hŒ°Orcs, fearsome creatures of medieval folklore, are the Dwarves' natural
enemies.  Similarly, the ORC unwinder was created in opposition to the
complexity and slowness of DWARF.”h]”hŒ²Orcs, fearsome creatures of medieval folklore, are the Dwarvesâ€™ natural
enemies.  Similarly, the ORC unwinder was created in opposition to the
complexity and slowness of DWARF.”…””}”(hjé  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K¢hjØ  hžhubhÛ)”}”(hX}  "Although Orcs rarely consider multiple solutions to a problem, they do
excel at getting things done because they are creatures of action, not
thought." [3]_  Similarly, unlike the esoteric DWARF unwinder, the
veracious ORC unwinder wastes no time or siloconic effort decoding
variable-length zero-extended unsigned-integer byte-coded
state-machine-based debug information entries.”h]”(hŒâ€œAlthough Orcs rarely consider multiple solutions to a problem, they do
excel at getting things done because they are creatures of action, not
thought.â€ ”…””}”(hj÷  hžhhŸNh Nubj(  )”}”(hŒ[3]_”h]”hŒ3”…””}”(hjÿ  hžhhŸNh Nubah}”(h]”Œid3”ah ]”h"]”h$]”h&]”j8  Œid6”j:  j;  uh1j'  hj÷  j<  KubhŒà  Similarly, unlike the esoteric DWARF unwinder, the
veracious ORC unwinder wastes no time or siloconic effort decoding
variable-length zero-extended unsigned-integer byte-coded
state-machine-based debug information entries.”…””}”(hj÷  hžhhŸNh Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K¦hjØ  hžhubhÛ)”}”(hŒ§Similar to how Orcs frequently unravel the well-intentioned plans of
their adversaries, the ORC unwinder frequently unravels stacks with
brutal, unyielding efficiency.”h]”hŒ§Similar to how Orcs frequently unravel the well-intentioned plans of
their adversaries, the ORC unwinder frequently unravels stacks with
brutal, unyielding efficiency.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K­hjØ  hžhubhÛ)”}”(hŒ&ORC stands for Oops Rewind Capability.”h]”hŒ&ORC stands for Oops Rewind Capability.”…””}”(hj'  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K±hjØ  hžhubhŒfootnote”“”)”}”(hŒAhttps://lore.kernel.org/r/20170602104048.jkkzssljsompjdwy@suse.de”h]”(hŒlabel”“”)”}”(hŒ1”h]”hŒ1”…””}”(hj=  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j;  hj7  ubhÛ)”}”(hj9  h]”hŒ	reference”“”)”}”(hj9  h]”hŒAhttps://lore.kernel.org/r/20170602104048.jkkzssljsompjdwy@suse.de”…””}”(hjP  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”Œrefuri”j9  uh1jN  hjK  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K´hj7  ubeh}”(h]”j9  ah ]”h"]”Œ1”ah$]”h&]”j3  aj:  j;  uh1j5  hŸh³h K´hjØ  hžhj<  Kubj6  )”}”(hŒFhttps://lore.kernel.org/r/d2ca5435-6386-29b8-db87-7f227c2b713a@suse.cz”h]”(j<  )”}”(hŒ2”h]”hŒ2”…””}”(hjo  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j;  hjk  ubhÛ)”}”(hjm  h]”jO  )”}”(hjm  h]”hŒFhttps://lore.kernel.org/r/d2ca5435-6386-29b8-db87-7f227c2b713a@suse.cz”…””}”(hj€  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”Œrefuri”jm  uh1jN  hj}  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h Kµhjk  ubeh}”(h]”j×  ah ]”h"]”Œ2”ah$]”h&]”jÒ  aj:  j;  uh1j5  hŸh³h KµhjØ  hžhj<  Kubj6  )”}”(hŒ,http://dustin.wikidot.com/half-orcs-and-orcs”h]”(j<  )”}”(hŒ3”h]”hŒ3”…””}”(hjŸ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j;  hj›  ubhÛ)”}”(hj  h]”jO  )”}”(hj  h]”hŒ,http://dustin.wikidot.com/half-orcs-and-orcs”…””}”(hj°  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”Œrefuri”j  uh1jN  hj­  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hÚhŸh³h K¶hj›  ubeh}”(h]”j  ah ]”h"]”Œ3”ah$]”h&]”j	  aj:  j;  uh1j5  hŸh³h K¶hjØ  hžhj<  Kubeh}”(h]”Œ	etymology”ah ]”h"]”Œ	etymology”ah$]”h&]”uh1h´hh¶hžhhŸh³h K ubeh}”(h]”Œorc-unwinder”ah ]”h"]”Œorc unwinder”ah$]”h&]”uh1h´hhhžhhŸh³h Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”h³uh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(h¹NŒ	generator”NŒ	datestamp”NŒsource_link”NŒ
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halt_level”KŒexit_status_level”KŒdebug”NŒwarning_stream”NŒ	traceback”ˆŒinput_encoding”Œ	utf-8-sig”Œinput_encoding_error_handler”Œstrict”Œoutput_encoding”Œutf-8”Œoutput_encoding_error_handler”jþ  Œerror_encoding”Œutf-8”Œerror_encoding_error_handler”Œbackslashreplace”Œlanguage_code”Œen”Œrecord_dependencies”NŒconfig”NŒ	id_prefix”hŒauto_id_prefix”Œid”Œdump_settings”NŒdump_internals”NŒdump_transforms”NŒdump_pseudo_xml”NŒexpose_internals”NŒstrict_visitor”NŒ_disable_config”NŒ_source”h³Œ_destination”NŒ_config_files”]”Œ7/var/lib/git/docbuild/linux/Documentation/docutils.conf”aŒfile_insertion_enabled”ˆŒraw_enabled”KŒline_length_limit”M'Œpep_references”NŒpep_base_url”Œhttps://peps.python.org/”Œpep_file_url_template”Œpep-%04d”Œrfc_references”NŒrfc_base_url”Œ&https://datatracker.ietf.org/doc/html/”Œ	tab_width”KŒtrim_footnote_reference_space”‰Œsyntax_highlight”Œlong”Œsmart_quotes”ˆŒsmartquotes_locales”]”Œcharacter_level_inline_markup”‰Œdoctitle_xform”‰Œdocinfo_xform”KŒsectsubtitle_xform”‰Œimage_loading”Œlink”Œembed_stylesheet”‰Œcloak_email_addresses”ˆŒsection_self_link”‰Œenv”NubŒreporter”NŒindirect_targets”]”Œsubstitution_defs”}”Œsubstitution_names”}”Œrefnames”}”(Œ1”]”j)  aŒ2”]”jÈ  aŒ3”]”jÿ  auŒrefids”}”Œnameids”}”(jØ  jÕ  j  j  jž  j›  j  j  j’  j  jÕ  jÒ  jÐ  jÍ  jh  j9  j˜  j×  jÈ  j  uŒ	nametypes”}”(jØ  ‰j  ‰jž  ‰j  ‰j’  ‰jÕ  ‰jÐ  ‰jh  ˆj˜  ˆjÈ  ˆuh}”(jÕ  h¶j  hÉj›  j  j3  j)  j  j¡  jÒ  jÈ  j  j  jÒ  j•  jÍ  jØ  j	  jÿ  j9  j7  j×  jk  j  j›  uŒfootnote_refs”}”(j>  ]”j)  aj@  ]”jÈ  ajB  ]”jÿ  auŒcitation_refs”}”Œautofootnotes”]”Œautofootnote_refs”]”Œsymbol_footnotes”]”Œsymbol_footnote_refs”]”Œ	footnotes”]”(j7  jk  j›  eŒ	citations”]”Œautofootnote_start”KŒsymbol_footnote_start”K Œ
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