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* x86, bitops: Correct the assembly constraints to testing bitopsH. Peter Anvin2013-12-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | In checkin: 0c44c2d0f459 x86: Use asm goto to implement better modify_and_test() functions the various functions which do modify and test were unified and optimized using "asm goto". However, this change missed the detail that the bitops require an "Ir" constraint rather than an "er" constraint ("I" = integer constant from 0-31, "e" = signed 32-bit integer constant). This would cause code to miscompile if these functions were used on constant bit positions 32-255 and the build to fail if used on constant bit positions above 255. Add the constraints as a parameter to the GEN_BINARY_RMWcc() macro to avoid this problem. Reported-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/529E8719.4070202@zytor.com
* x86: Use asm goto to implement better modify_and_test() functionsPeter Zijlstra2013-09-251-24/+5
| | | | | | | | | | | | | | | | | | Linus suggested using asm goto to get rid of the typical SETcc + TEST instruction pair -- which also clobbers an extra register -- for our typical modify_and_test() functions. Because asm goto doesn't allow output fields it has to include an unconditinal memory clobber when it changes a memory variable to force a reload. Luckily all atomic ops already imply a compiler barrier to go along with their memory barrier semantics. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-0mtn9siwbeo1d33bap1422se@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86, 386 removal: Remove CONFIG_XADDH. Peter Anvin2012-11-291-16/+0
| | | | | | | | All 486+ CPUs support XADD, so remove the fallback 386 support code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1354132230-21854-4-git-send-email-hpa@linux.intel.com
* atomic: implement generic atomic_dec_if_positive()Shaohua Li2012-10-091-24/+0
| | | | | | | | | | | | | | | | | | | | | The x86 implementation of atomic_dec_if_positive is quite generic, so make it available to all architectures. This is needed for "swap: add a simple detector for inappropriate swapin readahead". [akpm@linux-foundation.org: do the "#define foo foo" trick in the conventional manner] Signed-off-by: Shaohua Li <shli@fusionio.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Simek <monstr@monstr.eu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* UAPI: (Scripted) Convert #include "..." to #include <path/...> in kernel ↵David Howells2012-10-021-2/+2
| | | | | | | | | | | | system headers Convert #include "..." to #include <path/...> in kernel system headers. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
* x86: Use xadd helper more widelyJeremy Fitzhardinge2011-08-291-6/+2
| | | | | | | | This covers the trivial cases from open-coded xadd to the xadd macros. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Link: http://lkml.kernel.org/r/4E5BCC40.3030501@goop.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* atomic: cleanup asm-generic atomic*.h inclusionArun Sharma2011-07-261-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | After changing all consumers of atomics to include <linux/atomic.h>, we ran into some compile time errors due to this dependency chain: linux/atomic.h -> asm/atomic.h -> asm-generic/atomic-long.h where atomic-long.h could use funcs defined later in linux/atomic.h without a prototype. This patches moves the code that includes asm-generic/atomic*.h to linux/atomic.h. Archs that need <asm-generic/atomic64.h> need to select CONFIG_GENERIC_ATOMIC64 from now on (some of them used to include it unconditionally). Compile tested on i386 and x86_64 with allnoconfig. Signed-off-by: Arun Sharma <asharma@fb.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> 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>
* atomic: move atomic_add_unless to generic codeArun Sharma2011-07-261-4/+4
| | | | | | | | | | | | | | This is in preparation for more generic atomic primitives based on __atomic_add_unless. Signed-off-by: Arun Sharma <asharma@fb.com> Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> 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>
* atomic: use <linux/atomic.h>Arun Sharma2011-07-261-1/+0
| | | | | | | | | | | | | | 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-atomic-for-linus' of ↵Linus Torvalds2010-05-181-0/+23
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * x86: Implement atomic[64]_dec_if_positive()Luca Barbieri2010-03-011-0/+23
| | | | | | | | | | | | | | | | | | | | | | Add support for atomic_dec_if_positive(), and atomic64_dec_if_positive() for x86-64. atomic64_dec_if_positive() for x86-32 was already implemented in a previous patch. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267183361-20775-2-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | atomic_t: Cast to volatile when accessing atomic variablesAnton Blanchard2010-05-171-1/+1
|/ | | | | | | | In preparation for removing volatile from the atomic_t definition, this patch adds a volatile cast to all the atomic read functions. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: Mark atomic irq ops raw for 32bit legacyIngo Molnar2010-02-161-2/+2
| | | | | | | | | | The atomic ops emulation for 32bit legacy CPUs floods the tracer with irq off/on entries. The irq disabled regions are short and therefor not interesting when chasing long irq disabled latencies. Mark them raw and keep them out of the trace. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: Merge asm/atomic_{32,64}.hBrian Gerst2010-01-071-2/+297
| | | | | | | | | Merge the now identical code from asm/atomic_32.h and asm/atomic_64.h into asm/atomic.h. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1262883215-4034-4-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: ... and asm-x86 moveAl Viro2008-10-221-0/+5
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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