From: Hiro Yoshioka Use the x86 cache-bypassing copy instructions for copy_from_user(). Some performance data are Total of GLOBAL_POWER_EVENTS (CPU cycle samples) 2.6.12.4.orig 1921587 2.6.12.4.nt 1599424 1599424/1921587=83.23% (16.77% reduction) BSQ_CACHE_REFERENCE (L3 cache miss) 2.6.12.4.orig 57427 2.6.12.4.nt 20858 20858/57427=36.32% (63.7% reduction) L3 cache miss reduction of __copy_from_user_ll samples % 37408 65.1412 vmlinux __copy_from_user_ll 23 0.1103 vmlinux __copy_user_zeroing_intel_nocache 23/37408=0.061% (99.94% reduction) Top 5 of 2.6.12.4.nt Counted GLOBAL_POWER_EVENTS events (time during which processor is not stopped) with a unit mask of 0x01 (mandatory) count 100000 samples % app name symbol name 128392 8.0274 vmlinux __copy_user_zeroing_intel_nocache 64206 4.0143 vmlinux journal_add_journal_head 59746 3.7355 vmlinux do_get_write_access 47674 2.9807 vmlinux journal_put_journal_head 46021 2.8774 vmlinux journal_dirty_metadata pattern9-0-cpu4-0-09011728/summary.out Counted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x3f (multiple flags) count 3000 samples % app name symbol name 69755 4.2861 vmlinux __copy_user_zeroing_intel_nocache 55685 3.4215 vmlinux journal_add_journal_head 52371 3.2179 vmlinux __find_get_block 45504 2.7960 vmlinux journal_put_journal_head 36005 2.2123 vmlinux journal_stop pattern9-0-cpu4-0-09011744/summary.out Counted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x200 (read 3rd level cache miss) count 3000 samples % app name symbol name 1147 5.4994 vmlinux journal_add_journal_head 881 4.2240 vmlinux journal_dirty_data 872 4.1809 vmlinux blk_rq_map_sg 734 3.5192 vmlinux journal_commit_transaction 617 2.9582 vmlinux radix_tree_delete pattern9-0-cpu4-0-09011731/summary.out iozone results are original 2.6.12.4 CPU time = 207.768 sec cache aware CPU time = 184.783 sec (three times run) 184.783/207.768=88.94% (11.06% reduction) original: pattern9-0-cpu4-0-08191720/iozone.out: CPU Utilization: Wall time 45.997 CPU time 64.527 CPU utilization 140.28 % pattern9-0-cpu4-0-08191741/iozone.out: CPU Utilization: Wall time 46.878 CPU time 71.933 CPU utilization 153.45 % pattern9-0-cpu4-0-08191743/iozone.out: CPU Utilization: Wall time 45.152 CPU time 71.308 CPU utilization 157.93 % cache awre: pattern9-0-cpu4-0-09011728/iozone.out: CPU Utilization: Wall time 44.842 CPU time 62.465 CPU utilization 139.30 % pattern9-0-cpu4-0-09011731/iozone.out: CPU Utilization: Wall time 44.718 CPU time 59.273 CPU utilization 132.55 % pattern9-0-cpu4-0-09011744/iozone.out: CPU Utilization: Wall time 44.367 CPU time 63.045 CPU utilization 142.10 % Signed-off-by: Andrew Morton --- arch/i386/lib/usercopy.c | 119 ++++++++++++++++++++++++++++++++++++++++++++- include/asm-i386/uaccess.h | 31 +++++++++++ mm/filemap.c | 2 mm/filemap.h | 4 - 4 files changed, 152 insertions(+), 4 deletions(-) diff -puN arch/i386/lib/usercopy.c~x86-cache-pollution-aware-__copy_from_user_ll arch/i386/lib/usercopy.c --- devel/arch/i386/lib/usercopy.c~x86-cache-pollution-aware-__copy_from_user_ll 2005-09-07 20:10:32.000000000 -0700 +++ devel-akpm/arch/i386/lib/usercopy.c 2005-09-07 20:10:32.000000000 -0700 @@ -425,6 +425,107 @@ __copy_user_zeroing_intel(void *to, cons : "eax", "edx", "memory"); return size; } + +/* Non Temporal Hint version of __copy_user_zeroing_intel */ +/* It is cache aware. */ +/* hyoshiok@miraclelinux.com */ +static unsigned long +__copy_user_zeroing_intel_nocache(void *to, const void __user *from, unsigned long size) +{ + int d0, d1; + + __asm__ __volatile__( + " .align 2,0x90\n" + "0: movl 32(%4), %%eax\n" + " cmpl $67, %0\n" + " jbe 2f\n" + "1: movl 64(%4), %%eax\n" + " .align 2,0x90\n" + "2: movl 0(%4), %%eax\n" + "21: movl 4(%4), %%edx\n" + " movnti %%eax, 0(%3)\n" + " movnti %%edx, 4(%3)\n" + "3: movl 8(%4), %%eax\n" + "31: movl 12(%4),%%edx\n" + " movnti %%eax, 8(%3)\n" + " movnti %%edx, 12(%3)\n" + "4: movl 16(%4), %%eax\n" + "41: movl 20(%4), %%edx\n" + " movnti %%eax, 16(%3)\n" + " movnti %%edx, 20(%3)\n" + "10: movl 24(%4), %%eax\n" + "51: movl 28(%4), %%edx\n" + " movnti %%eax, 24(%3)\n" + " movnti %%edx, 28(%3)\n" + "11: movl 32(%4), %%eax\n" + "61: movl 36(%4), %%edx\n" + " movnti %%eax, 32(%3)\n" + " movnti %%edx, 36(%3)\n" + "12: movl 40(%4), %%eax\n" + "71: movl 44(%4), %%edx\n" + " movnti %%eax, 40(%3)\n" + " movnti %%edx, 44(%3)\n" + "13: movl 48(%4), %%eax\n" + "81: movl 52(%4), %%edx\n" + " movnti %%eax, 48(%3)\n" + " movnti %%edx, 52(%3)\n" + "14: movl 56(%4), %%eax\n" + "91: movl 60(%4), %%edx\n" + " movnti %%eax, 56(%3)\n" + " movnti %%edx, 60(%3)\n" + " addl $-64, %0\n" + " addl $64, %4\n" + " addl $64, %3\n" + " cmpl $63, %0\n" + " ja 0b\n" + " sfence \n" + "5: movl %0, %%eax\n" + " shrl $2, %0\n" + " andl $3, %%eax\n" + " cld\n" + "6: rep; movsl\n" + " movl %%eax,%0\n" + "7: rep; movsb\n" + "8:\n" + ".section .fixup,\"ax\"\n" + "9: lea 0(%%eax,%0,4),%0\n" + "16: pushl %0\n" + " pushl %%eax\n" + " xorl %%eax,%%eax\n" + " rep; stosb\n" + " popl %%eax\n" + " popl %0\n" + " jmp 8b\n" + ".previous\n" + ".section __ex_table,\"a\"\n" + " .align 4\n" + " .long 0b,16b\n" + " .long 1b,16b\n" + " .long 2b,16b\n" + " .long 21b,16b\n" + " .long 3b,16b\n" + " .long 31b,16b\n" + " .long 4b,16b\n" + " .long 41b,16b\n" + " .long 10b,16b\n" + " .long 51b,16b\n" + " .long 11b,16b\n" + " .long 61b,16b\n" + " .long 12b,16b\n" + " .long 71b,16b\n" + " .long 13b,16b\n" + " .long 81b,16b\n" + " .long 14b,16b\n" + " .long 91b,16b\n" + " .long 6b,9b\n" + " .long 7b,16b\n" + ".previous" + : "=&c"(size), "=&D" (d0), "=&S" (d1) + : "1"(to), "2"(from), "0"(size) + : "eax", "edx", "memory"); + return size; +} + #else /* * Leave these declared but undefined. They should not be any references to @@ -434,6 +535,8 @@ unsigned long __copy_user_zeroing_intel(void *to, const void __user *from, unsigned long size); unsigned long __copy_user_intel(void __user *to, const void *from, unsigned long size); +unsigned long +__copy_user_zeroing_intel_nocache(void *to, const void __user *from, unsigned long size); #endif /* CONFIG_X86_INTEL_USERCOPY */ /* Generic arbitrary sized copy. */ @@ -515,7 +618,6 @@ do { \ : "memory"); \ } while (0) - unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned long n) { BUG_ON((long) n < 0); @@ -588,6 +690,21 @@ __copy_from_user_ll(void *to, const void } EXPORT_SYMBOL(__copy_from_user_ll); +unsigned long +__copy_from_user_ll_nocache(void *to, const void __user *from, unsigned long n) +{ + BUG_ON((long)n < 0); +#ifdef CONFIG_X86_INTEL_USERCOPY + if ( n > 64 && cpu_has_xmm2) + n = __copy_user_zeroing_intel_nocache(to, from, n); + else + __copy_user_zeroing(to, from, n); +#else + __copy_user_zeroing(to, from, n); +#endif + return n; +} + /** * copy_to_user: - Copy a block of data into user space. * @to: Destination address, in user space. diff -puN include/asm-i386/uaccess.h~x86-cache-pollution-aware-__copy_from_user_ll include/asm-i386/uaccess.h --- devel/include/asm-i386/uaccess.h~x86-cache-pollution-aware-__copy_from_user_ll 2005-09-07 20:10:32.000000000 -0700 +++ devel-akpm/include/asm-i386/uaccess.h 2005-09-07 20:10:32.000000000 -0700 @@ -389,6 +389,8 @@ unsigned long __must_check __copy_to_use const void *from, unsigned long n); unsigned long __must_check __copy_from_user_ll(void *to, const void __user *from, unsigned long n); +unsigned long __must_check __copy_from_user_ll_nocache(void *to, + const void __user *from, unsigned long n); /* * Here we special-case 1, 2 and 4-byte copy_*_user invocations. On a fault @@ -478,11 +480,40 @@ __copy_from_user_inatomic(void *to, cons } static inline unsigned long +__copy_from_user_inatomic_nocache(void *to, const void __user *from, unsigned long n) +{ + if (__builtin_constant_p(n)) { + unsigned long ret; + + switch (n) { + case 1: + __get_user_size(*(u8 *)to, from, 1, ret, 1); + return ret; + case 2: + __get_user_size(*(u16 *)to, from, 2, ret, 2); + return ret; + case 4: + __get_user_size(*(u32 *)to, from, 4, ret, 4); + return ret; + } + } + return __copy_from_user_ll_nocache(to, from, n); +} + +static inline unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n) { might_sleep(); return __copy_from_user_inatomic(to, from, n); } + +static inline unsigned long +__copy_from_user_nocache(void *to, const void __user *from, unsigned long n) +{ + might_sleep(); + return __copy_from_user_inatomic_nocache(to, from, n); +} + unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n); unsigned long __must_check copy_from_user(void *to, diff -puN mm/filemap.c~x86-cache-pollution-aware-__copy_from_user_ll mm/filemap.c --- devel/mm/filemap.c~x86-cache-pollution-aware-__copy_from_user_ll 2005-09-07 20:10:32.000000000 -0700 +++ devel-akpm/mm/filemap.c 2005-09-07 20:10:32.000000000 -0700 @@ -1732,7 +1732,7 @@ __filemap_copy_from_user_iovec(char *vad int copy = min(bytes, iov->iov_len - base); base = 0; - left = __copy_from_user_inatomic(vaddr, buf, copy); + left = __copy_from_user_inatomic_nocache(vaddr, buf, copy); copied += copy; bytes -= copy; vaddr += copy; diff -puN mm/filemap.h~x86-cache-pollution-aware-__copy_from_user_ll mm/filemap.h --- devel/mm/filemap.h~x86-cache-pollution-aware-__copy_from_user_ll 2005-09-07 20:10:32.000000000 -0700 +++ devel-akpm/mm/filemap.h 2005-09-07 20:10:32.000000000 -0700 @@ -34,13 +34,13 @@ filemap_copy_from_user(struct page *page int left; kaddr = kmap_atomic(page, KM_USER0); - left = __copy_from_user_inatomic(kaddr + offset, buf, bytes); + left = __copy_from_user_inatomic_nocache(kaddr + offset, buf, bytes); kunmap_atomic(kaddr, KM_USER0); if (left != 0) { /* Do it the slow way */ kaddr = kmap(page); - left = __copy_from_user(kaddr + offset, buf, bytes); + left = __copy_from_user_nocache(kaddr + offset, buf, bytes); kunmap(page); } return bytes - left; _