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* atomic: use <linux/atomic.h>Arun Sharma2011-07-261-1/+1
| | | | | | | | | | | | | | This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'x86-vdso-for-linus' of ↵Linus Torvalds2011-07-222-12/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-64, vdso: Do not allocate memory for the vDSO clocksource: Change __ARCH_HAS_CLOCKSOURCE_DATA to a CONFIG option x86, vdso: Drop now wrong comment Document the vDSO and add a reference parser ia64: Replace clocksource.fsys_mmio with generic arch data x86-64: Move vread_tsc and vread_hpet into the vDSO clocksource: Replace vread with generic arch data x86-64: Add --no-undefined to vDSO build x86-64: Allow alternative patching in the vDSO x86: Make alternative instruction pointers relative x86-64: Improve vsyscall emulation CS and RIP handling x86-64: Emulate legacy vsyscalls x86-64: Fill unused parts of the vsyscall page with 0xcc x86-64: Remove vsyscall number 3 (venosys) x86-64: Map the HPET NX x86-64: Remove kernel.vsyscall64 sysctl x86-64: Give vvars their own page x86-64: Document some of entry_64.S x86-64: Fix alignment of jiffies variable
| * x86: Make alternative instruction pointers relativeAndy Lutomirski2011-07-132-12/+8
| | | | | | | | | | | | | | | | | | This save a few bytes on x86-64 and means that future patches can apply alternatives to unrelocated code. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/ff64a6b9a1a3860ca4a7b8b6dc7b4754f9491cd7.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2011-07-226-208/+125
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Fix write lock scalability 64-bit issue x86: Unify rwsem assembly implementation x86: Unify rwlock assembly implementation x86, asm: Fix binutils 2.16 issue with __USER32_CS x86, asm: Cleanup thunk_64.S x86, asm: Flip RESTORE_ARGS arguments logic x86, asm: Flip SAVE_ARGS arguments logic x86, asm: Thin down SAVE/RESTORE_* asm macros
| * | x86: Fix write lock scalability 64-bit issueJan Beulich2011-07-212-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the write lock path simply subtracting RW_LOCK_BIAS there is, on large systems, the theoretical possibility of overflowing the 32-bit value that was used so far (namely if 128 or more CPUs manage to do the subtraction, but don't get to do the inverse addition in the failure path quickly enough). A first measure is to modify RW_LOCK_BIAS itself - with the new value chosen, it is good for up to 2048 CPUs each allowed to nest over 2048 times on the read path without causing an issue. Quite possibly it would even be sufficient to adjust the bias a little further, assuming that allowing for significantly less nesting would suffice. However, as the original value chosen allowed for even more nesting levels, to support more than 2048 CPUs (possible currently only for 64-bit kernels) the lock itself gets widened to 64 bits. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4E258E0D020000780004E3F0@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86: Unify rwsem assembly implementationJan Beulich2011-07-213-98/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than having two functionally identical implementations for 32- and 64-bit configurations, use the previously extended assembly abstractions to fold the rwsem two implementations into a shared one. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4E258DF3020000780004E3ED@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86: Unify rwlock assembly implementationJan Beulich2011-07-214-84/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than having two functionally identical implementations for 32- and 64-bit configurations, extend the existing assembly abstractions enough to fold the two rwlock implementations into a shared one. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4E258DD7020000780004E3EA@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86, asm: Cleanup thunk_64.SBorislav Petkov2011-06-031-27/+19
| |/ | | | | | | | | | | | | | | | | | | Drop thunk_ra macro in favor of an additional argument to the thunk macro since their bodies are almost identical. Do a whitespace scrubbing and use CFI-aware macros for full annotation. Signed-off-by: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/1306873314-32523-5-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86, perf: Make copy_from_user_nmi() a library functionRobert Richter2011-07-212-1/+44
|/ | | | | | | | | | | copy_from_user_nmi() is used in oprofile and perf. Moving it to other library functions like copy_from_user(). As this is x86 code for 32 and 64 bits, create a new file usercopy.c for unified code. Signed-off-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110607172413.GJ20052@erda.amd.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
*-. Merge branches 'x86-apic-for-linus', 'x86-asm-for-linus' and ↵Linus Torvalds2011-05-191-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, apic: Print verbose error interrupt reason on apic=debug * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Demacro CONFIG_PARAVIRT cpu accessors * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Fix mrst sparse complaints x86: Fix spelling error in the memcpy() source code comment x86, mpparse: Remove unnecessary variable
| | * Merge commit 'v2.6.39-rc6' into x86/cleanupsIngo Molnar2011-05-071-4/+10
| | |\ | | |/ | |/| | | | | | | | | | Merge reason: move to a (much) newer upstream base. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * x86: Fix spelling error in the memcpy() source code commentBart Van Assche2011-05-011-1/+1
| | | | | | | | | | | | | | | | | | | | | Signed-off-by: Bart Van Assche <bvanassche@acm.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: http://lkml.kernel.org/r/201105011409.21629.bvanassche@acm.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | x86, 64-bit: Fix copy_[to/from]_user() checks for the userspace address limitJiri Olsa2011-05-181-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As reported in BZ #30352: https://bugzilla.kernel.org/show_bug.cgi?id=30352 there's a kernel bug related to reading the last allowed page on x86_64. The _copy_to_user() and _copy_from_user() functions use the following check for address limit: if (buf + size >= limit) fail(); while it should be more permissive: if (buf + size > limit) fail(); That's because the size represents the number of bytes being read/write from/to buf address AND including the buf address. So the copy function will actually never touch the limit address even if "buf + size == limit". Following program fails to use the last page as buffer due to the wrong limit check: #include <sys/mman.h> #include <sys/socket.h> #include <assert.h> #define PAGE_SIZE (4096) #define LAST_PAGE ((void*)(0x7fffffffe000)) int main() { int fds[2], err; void * ptr = mmap(LAST_PAGE, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); assert(ptr == LAST_PAGE); err = socketpair(AF_LOCAL, SOCK_STREAM, 0, fds); assert(err == 0); err = send(fds[0], ptr, PAGE_SIZE, 0); perror("send"); assert(err == PAGE_SIZE); err = recv(fds[1], ptr, PAGE_SIZE, MSG_WAITALL); perror("recv"); assert(err == PAGE_SIZE); return 0; } The other place checking the addr limit is the access_ok() function, which is working properly. There's just a misleading comment for the __range_not_ok() macro - which this patch fixes as well. The last page of the user-space address range is a guard page and Brian Gerst observed that the guard page itself due to an erratum on K8 cpus (#121 Sequential Execution Across Non-Canonical Boundary Causes Processor Hang). However, the test code is using the last valid page before the guard page. The bug is that the last byte before the guard page can't be read because of the off-by-one error. The guard page is left in place. This bug would normally not show up because the last page is part of the process stack and never accessed via syscalls. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Brian Gerst <brgerst@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/1305210630-7136-1-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | x86, mem: memset_64.S: Optimize memset by enhanced REP MOVSB/STOSBFenghua Yu2011-05-171-12/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support memset() with enhanced rep stosb. On processors supporting enhanced REP MOVSB/STOSB, the alternative memset_c_e function using enhanced rep stosb overrides the fast string alternative memset_c and the original function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-10-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | x86, mem: memmove_64.S: Optimize memmove by enhanced REP MOVSB/STOSBFenghua Yu2011-05-171-1/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support memmove() by enhanced rep movsb. On processors supporting enhanced REP MOVSB/STOSB, the alternative memmove() function using enhanced rep movsb overrides the original function. The patch doesn't change the backward memmove case to use enhanced rep movsb. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-9-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | x86, mem: memcpy_64.S: Optimize memcpy by enhanced REP MOVSB/STOSBFenghua Yu2011-05-171-13/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support memcpy() with enhanced rep movsb. On processors supporting enhanced rep movsb, the alternative memcpy() function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-8-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSBFenghua Yu2011-05-171-10/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | x86, mem: clear_page_64.S: Support clear_page() with enhanced REP MOVSB/STOSBFenghua Yu2011-05-171-9/+24
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel processors are adding enhancements to REP MOVSB/STOSB and the use of REP MOVSB/STOSB for optimal memcpy/memset or similar functions is recommended. Enhancement availability is indicated by CPUID.7.0.EBX[9] (Enhanced REP MOVSB/ STOSB). Support clear_page() with rep stosb for processor supporting enhanced REP MOVSB /STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative clear_page_c_e function using enhanced REP STOSB overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-6-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | percpu: Omit segment prefix in the UP case for cmpxchg_doubleChristoph Lameter2011-03-271-4/+10
|/ | | | | | | | Omit the segment prefix in the UP case. GS is not used then and we will generate segfaults if cmpxchg16b is used otherwise. Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds2011-03-183-123/+123
|\ | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Flush TLB if PGD entry is changed in i386 PAE mode x86, dumpstack: Correct stack dump info when frame pointer is available x86: Clean up csum-copy_64.S a bit x86: Fix common misspellings x86: Fix misspelling and align params x86: Use PentiumPro-optimized partial_csum() on VIA C7
| * x86: Clean up csum-copy_64.S a bitIngo Molnar2011-03-181-120/+120
| | | | | | | | | | | | | | | | | | The many stray whitespaces and other uncleanlinesses made this code almost unreadable to me - so fix those. No changes to the code. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: Fix common misspellingsLucas De Marchi2011-03-183-4/+4
| | | | | | | | | | | | | | | | | | They were generated by 'codespell' and then manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: trivial@kernel.org LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'for-2.6.39' of ↵Linus Torvalds2011-03-162-0/+60
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: percpu, x86: Add arch-specific this_cpu_cmpxchg_double() support percpu: Generic support for this_cpu_cmpxchg_double() alpha: use L1_CACHE_BYTES for cacheline size in the linker script percpu: align percpu readmostly subsection to cacheline Fix up trivial conflict in arch/x86/kernel/vmlinux.lds.S due to the percpu alignment having changed ("x86: Reduce back the alignment of the per-CPU data section")
| * percpu, x86: Add arch-specific this_cpu_cmpxchg_double() supportChristoph Lameter2011-02-282-0/+60
| | | | | | | | | | | | | | | | | | | | | | Support this_cpu_cmpxchg_double() using the cmpxchg16b and cmpxchg8b instructions. -tj: s/percpu_cmpxchg16b/percpu_cmpxchg16b_double/ for consistency and other cosmetic changes. Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | Merge branch 'x86-mem-for-linus' of ↵Linus Torvalds2011-03-152-192/+197
|\ \ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-64, mem: Convert memmove() to assembly file and fix return value bug
| * | x86-64, mem: Convert memmove() to assembly file and fix return value bugFenghua Yu2011-01-252-192/+197
| |/ | | | | | | | | | | | | | | | | | | | | | | | | memmove_64.c only implements memmove() function which is completely written in inline assembly code. Therefore it doesn't make sense to keep the assembly code in .c file. Currently memmove() doesn't store return value to rax. This may cause issue if caller uses the return value. The patch fixes this issue. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> LKML-Reference: <1295314755-6625-1-git-send-email-fenghua.yu@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86: Fix a bogus unwind annotation in lib/semaphore_32.SJan Beulich2011-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | 'simple' would have required specifying current frame address and return address location manually, but that's obviously not the case (and not necessary) here. Signed-off-by: Jan Beulich <jbeulich@novell.com> LKML-Reference: <4D6D1082020000780003454C@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: Remove unused bits from lib/thunk_*.SJan Beulich2011-02-282-45/+0
| | | | | | | | | | | | | | | | | | Some of the items removed were apparently never used, others simply didn't get removed with their last user. Signed-off-by: Jan Beulich <jbeulich@novell.com> LKML-Reference: <4D6BD3A002000078000341F1@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: Use {push,pop}_cfi in more placesJan Beulich2011-02-284-74/+37
| | | | | | | | | | | | | | | | | | Cleaning up and shortening code... Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Alexander van Heukelum <heukelum@fastmail.fm> LKML-Reference: <4D6BD35002000078000341DA@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86-64: Add CFI annotations to lib/rwsem_64.SJan Beulich2011-02-281-22/+34
|/ | | | | | | | | These weren't part of the initial commit of this code. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Alexander van Heukelum <heukelum@fastmail.fm> LKML-Reference: <4D6BCDFF02000078000341B0@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: udelay: Use this_cpu_read to avoid address calculationChristoph Lameter2011-01-041-1/+1
| | | | | | | | | The code will use a segment prefix instead of doing the lookup and calculation. Signed-off-by: Christoph Lameter <cl@linux.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* x86, mem: Optimize memmove for small size and unaligned casesMa Ling2010-09-242-76/+362
| | | | | | | | | | | | | | | movs instruction will combine data to accelerate moving data, however we need to concern two cases about it. 1. movs instruction need long lantency to startup, so here we use general mov instruction to copy data. 2. movs instruction is not good for unaligned case, even if src offset is 0x10, dest offset is 0x0, we avoid and handle the case by general mov instruction. Signed-off-by: Ma Ling <ling.ma@intel.com> LKML-Reference: <1284664360-6138-1-git-send-email-ling.ma@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, mem: Optimize memcpy by avoiding memory false dependeceMa Ling2010-08-232-59/+105
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All read operations after allocation stage can run speculatively, all write operation will run in program order, and if addresses are different read may run before older write operation, otherwise wait until write commit. However CPU don't check each address bit, so read could fail to recognize different address even they are in different page.For example if rsi is 0xf004, rdi is 0xe008, in following operation there will generate big performance latency. 1. movq (%rsi), %rax 2. movq %rax, (%rdi) 3. movq 8(%rsi), %rax 4. movq %rax, 8(%rdi) If %rsi and rdi were in really the same meory page, there are TRUE read-after-write dependence because instruction 2 write 0x008 and instruction 3 read 0x00c, the two address are overlap partially. Actually there are in different page and no any issues, but without checking each address bit CPU could think they are in the same page, and instruction 3 have to wait for instruction 2 to write data into cache from write buffer, then load data from cache, the cost time read spent is equal to mfence instruction. We may avoid it by tuning operation sequence as follow. 1. movq 8(%rsi), %rax 2. movq %rax, 8(%rdi) 3. movq (%rsi), %rax 4. movq %rax, (%rdi) Instruction 3 read 0x004, instruction 2 write address 0x010, no any dependence. At last on Core2 we gain 1.83x speedup compared with original instruction sequence. In this patch we first handle small size(less 20bytes), then jump to different copy mode. Based on our micro-benchmark small bytes from 1 to 127 bytes, we got up to 2X improvement, and up to 1.5X improvement for 1024 bytes on Corei7. (We use our micro-benchmark, and will do further test according to your requirment) Signed-off-by: Ma Ling <ling.ma@intel.com> LKML-Reference: <1277753065-18610-1-git-send-email-ling.ma@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, mem: Don't implement forward memmove() as memcpy()Ma, Ling2010-08-232-16/+68
| | | | | | | | | | | memmove() allow source and destination address to be overlap, but there is no such limitation for memcpy(). Therefore, explicitly implement memmove() in both the forwards and backward directions, to give us the ability to optimize memcpy(). Signed-off-by: Ma Ling <ling.ma@intel.com> LKML-Reference: <C10D3FB0CD45994C8A51FEC1227CE22F0E483AD86A@shsmsx502.ccr.corp.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* Merge branch 'x86/urgent' of ↵Linus Torvalds2010-08-131-108/+130
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, asm: Use a lower case name for the end macro in atomic64_386_32.S x86, asm: Refactor atomic64_386_32.S to support old binutils and be cleaner x86: Document __phys_reloc_hide() usage in __pa_symbol() x86, apic: Map the local apic when parsing the MP table.
| * x86, asm: Use a lower case name for the end macro in atomic64_386_32.SLuca Barbieri2010-08-121-18/+20
| | | | | | | | | | | | | | | | | | Use a lowercase name for the end macro, which somehow fixes a binutils 2.16 problem. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <tip-30246557a06bb20618bed906a06d1e1e0faa8bb4@git.kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * x86, asm: Refactor atomic64_386_32.S to support old binutils and be cleanerLuca Barbieri2010-08-111-108/+128
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The old code didn't work on binutils 2.12 because setting a symbol to a register apparently requires a fairly recent version. This commit refactors the code to use the C preprocessor instead, and in the process makes the whole code a bit easier to understand. The object code produced is unchanged as expected. This fixes kernel bugzilla 16506. Reported-by: Dieter Stussy <kd6lvw+software@kd6lvw.ampr.org> Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@kernel.org> 2.6.35 LKML-Reference: <tip-*@git.kernel.org>
* | Merge branch 'x86-alternatives-for-linus' of ↵Linus Torvalds2010-08-065-5/+5
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-alternatives-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, alternatives: BUG on encountering an invalid CPU feature number x86, alternatives: Fix one more open-coded 8-bit alternative number x86, alternatives: Use 16-bit numbers for cpufeature index
| * | x86, alternatives: Fix one more open-coded 8-bit alternative numberH. Peter Anvin2010-07-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a missing case of an 8-bit alternative number, buried inside an assembly macro. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Reported-by: Yinghai Lu <yinhai@kernel.org> Cc: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <4C3BDDA3.2060900@kernel.org>
| * | x86, alternatives: Use 16-bit numbers for cpufeature indexH. Peter Anvin2010-07-074-4/+4
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | We already have cpufeature indicies above 255, so use a 16-bit number for the alternatives index. This consumes a padding field and so doesn't add any size, but it means that abusing the padding field to create assembly errors on overflow no longer works. We can retain the test simply by redirecting it to the .discard section, however. [ v3: updated to include open-coded locations ] Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> LKML-Reference: <tip-f88731e3068f9d1392ba71cc9f50f035d26a0d4f@git.kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | x86, asm: Merge cmpxchg_486_u64() and cmpxchg8b_emu()H. Peter Anvin2010-07-281-18/+0
| | | | | | | | | | | | | | | | | | | | | | We have two functions for doing exactly the same thing -- emulating cmpxchg8b on 486 and older hardware -- with different calling conventions, and yet doing the same thing. Drop the C version and use the assembly version, via alternatives, for both the local and non-local versions of cmpxchg8b. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> LKML-Reference: <AANLkTikAmaDPji-TVDarmG1yD=fwbffcsmEU=YEuP+8r@mail.gmail.com>
* | x86, asm: Move cmpxchg emulation code to arch/x86/libH. Peter Anvin2010-07-282-0/+73
|/ | | | | | | | | Move cmpxchg emulation code from arch/x86/kernel/cpu (which is otherwise CPU identification) to arch/x86/lib, where other emulation code lives already. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> LKML-Reference: <AANLkTikAmaDPji-TVDarmG1yD=fwbffcsmEU=YEuP+8r@mail.gmail.com>
* Merge branch 'x86-atomic-for-linus' of ↵Linus Torvalds2010-05-184-223/+451
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-atomic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Fix LOCK_PREFIX_HERE for uniprocessor build x86, atomic64: In selftest, distinguish x86-64 from 586+ x86-32: Fix atomic64_inc_not_zero return value convention lib: Fix atomic64_inc_not_zero test lib: Fix atomic64_add_unless return value convention x86-32: Fix atomic64_add_unless return value convention lib: Fix atomic64_add_unless test x86: Implement atomic[64]_dec_if_positive() lib: Only test atomic64_dec_if_positive on archs having it x86-32: Rewrite 32-bit atomic64 functions in assembly lib: Add self-test for atomic64_t x86-32: Allow UP/SMP lock replacement in cmpxchg64 x86: Add support for lock prefix in alternatives
| * Merge branch 'x86/asm' into x86/atomicH. Peter Anvin2010-04-294-27/+103
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge reason: Conflict between LOCK_PREFIX_HERE and relative alternatives pointers Resolved Conflicts: arch/x86/include/asm/alternative.h arch/x86/kernel/alternative.c Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86-32: Fix atomic64_inc_not_zero return value conventionLuca Barbieri2010-03-012-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | atomic64_inc_not_zero must return 1 if it perfomed the add and 0 otherwise. It was doing the opposite thing. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267469749-11878-6-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86-32: Fix atomic64_add_unless return value conventionLuca Barbieri2010-03-012-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | atomic64_add_unless must return 1 if it perfomed the add and 0 otherwise. The implementation did the opposite thing. Reported-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267469749-11878-3-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86-32: Rewrite 32-bit atomic64 functions in assemblyLuca Barbieri2010-02-254-223/+453
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch replaces atomic64_32.c with two assembly implementations, one for 386/486 machines using pushf/cli/popf and one for 586+ machines using cmpxchg8b. The cmpxchg8b implementation provides the following advantages over the current one: 1. Implements atomic64_add_unless, atomic64_dec_if_positive and atomic64_inc_not_zero 2. Uses the ZF flag changed by cmpxchg8b instead of doing a comparison 3. Uses custom register calling conventions that reduce or eliminate register moves to suit cmpxchg8b 4. Reads the initial value instead of using cmpxchg8b to do that. Currently we use lock xaddl and movl, which seems the fastest. 5. Does not use the lock prefix for atomic64_set 64-bit writes are already atomic, so we don't need that. We still need it for atomic64_read to avoid restoring a value changed in the meantime. 6. Allocates registers as well or better than gcc The 386 implementation provides support for 386 and 486 machines. 386/486 SMP is not supported (we dropped it), but such support can be added easily if desired. A pure assembly implementation is required due to the custom calling conventions, and desire to use %ebp in atomic64_add_return (we need 7 registers...), as well as the ability to use pushf/popf in the 386 code without an intermediate pop/push. The parameter names are changed to match the convention in atomic_64.h Changes in v3 (due to rebasing to tip/x86/asm): - Patches atomic64_32.h instead of atomic_32.h - Uses the CALL alternative mechanism from commit 1b1d9258181bae199dc940f4bd0298126b9a73d9 Changes in v2: - Merged 386 and cx8 support in the same patch - 386 support now done in assembly, C code no longer used at all - cmpxchg64 is used for atomic64_cmpxchg - stop using macros, use one-line inline functions instead - miscellanous changes and improvements Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267005265-27958-5-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | | Merge branch 'perf/urgent' into perf/coreIngo Molnar2010-05-071-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | Merge reason: Resolve patch dependency Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | Fix the x86_64 implementation of call_rwsem_wait()David Howells2010-05-041-1/+1
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | The x86_64 call_rwsem_wait() treats the active state counter part of the R/W semaphore state as being 16-bit when it's actually 32-bit (it's half of the 64-bit state). It should do "decl %edx" not "decw %dx". Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | perf, x86: Add INSTRUCTION_DECODER config flagIngo Molnar2010-03-101-1/+1
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PEBS+LBR decoding magic needs the insn_get_length() infrastructure to be able to decode x86 instruction length. So split it out of KPROBES dependency and make it enabled when either KPROBES or PERF_EVENTS is enabled. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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