* [PATCH 0/4] x86-32: improve atomic64_t functions (v3, for tip/x86/asm)
@ 2010-02-24 9:54 Luca Barbieri
2010-02-24 9:54 ` [PATCH 1/4] x86: add support for lock prefix in alternatives (v2) Luca Barbieri
` (3 more replies)
0 siblings, 4 replies; 11+ messages in thread
From: Luca Barbieri @ 2010-02-24 9:54 UTC (permalink / raw)
To: hpa; +Cc: mingo, a.p.zijlstra, akpm, linux-kernel, Luca Barbieri
Changes in v3:
- Dropped alternatives CALL patch because tip/x86/asm already had that
functionality
- Patch atomic64_32.h instead of atomic_32.h
Changes in v2:
- 386/486 is supported with a custom assembly implementation, the generic
implementation is no longer used/modified
- dropped SSE code
- changed CALL alternative code to use a custom alternative type:
insn parser no longer used
- several implementation improvements
- several formatting/style improvements
- merged 386 support into main patch
This patchset improves the atomic64_t functions on x86-32.
It also includes a testsuite that has been used to test this functionality
and can test any atomic64_t implementation.
It offers the following improvements:
1. Better code due to hand-written assembly (e.g. use of the ZF flag)
2. All atomic64 functions implemented
3. Support for 386/486 due to the ability to alternatively use either
the cmpxchg8b assembly implementation or the 386 cli/popf assembly one
The first patch adds functionality to the alternatives system to support
the new atomic64_t code.
A patch that improves cmpxchg64() using that functionality is also included.
To test this code, enable CONFIG_ATOMIC64_SELFTEST, compile for 386 and
boot normally and with "clearcpuid=8".
You should receive a message stating that the atomic64 test passed,
along with the selected configuration.
386/486 SMP is not supported, following existing practice, but the code
is structured to allow to very easily add such support.
Signed-off-by: Luca Barbieri <luca@luca-barbieri.com>
^ permalink raw reply [flat|nested] 11+ messages in thread* [PATCH 1/4] x86: add support for lock prefix in alternatives (v2) 2010-02-24 9:54 [PATCH 0/4] x86-32: improve atomic64_t functions (v3, for tip/x86/asm) Luca Barbieri @ 2010-02-24 9:54 ` Luca Barbieri 2010-02-26 5:12 ` [tip:x86/atomic] x86: Add support for lock prefix in alternatives tip-bot for Luca Barbieri 2010-04-29 23:24 ` [tip:x86/atomic] x86: Fix LOCK_PREFIX_HERE for uniprocessor build tip-bot for H. Peter Anvin 2010-02-24 9:54 ` [PATCH 2/4] x86-32: allow UP/SMP lock replacement in cmpxchg64 (v2) Luca Barbieri ` (2 subsequent siblings) 3 siblings, 2 replies; 11+ messages in thread From: Luca Barbieri @ 2010-02-24 9:54 UTC (permalink / raw) To: hpa; +Cc: mingo, a.p.zijlstra, akpm, linux-kernel, Luca Barbieri Changes in v2: - Naming change - Change label to not conflict with alternatives The current lock prefix UP/SMP alternative code doesn't allow LOCK_PREFIX to be used in alternatives code. This patch solves the problem by adding a new LOCK_PREFIX_ALTERNATIVE_PATCH macro that only records the lock prefix location but does not emit the prefix. The user of this macro can then start any alternative sequence with "lock" and have it UP/SMP patched. To make this work, the UP/SMP alternative code is changed to do the lock/DS prefix switching only if the byte actually contains a lock or DS prefix. Thus, if an alternative without the "lock" is selected, it will now do nothing instead of clobbering the code. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> --- arch/x86/include/asm/alternative.h | 8 +++++--- arch/x86/kernel/alternative.c | 6 ++++-- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 3b5b828..55fee12 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -28,12 +28,14 @@ */ #ifdef CONFIG_SMP -#define LOCK_PREFIX \ +#define LOCK_PREFIX_HERE \ ".section .smp_locks,\"a\"\n" \ _ASM_ALIGN "\n" \ - _ASM_PTR "661f\n" /* address */ \ + _ASM_PTR "671f\n" /* address */ \ ".previous\n" \ - "661:\n\tlock; " + "671:" + +#define LOCK_PREFIX LOCK_PREFIX_HERE "\n\tlock; " #else /* ! CONFIG_SMP */ #define LOCK_PREFIX "" diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 2589ea4..80b222e 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -244,7 +244,8 @@ static void alternatives_smp_lock(u8 **start, u8 **end, u8 *text, u8 *text_end) if (*ptr > text_end) continue; /* turn DS segment override prefix into lock prefix */ - text_poke(*ptr, ((unsigned char []){0xf0}), 1); + if (**ptr == 0x3e) + text_poke(*ptr, ((unsigned char []){0xf0}), 1); }; mutex_unlock(&text_mutex); } @@ -263,7 +264,8 @@ static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end if (*ptr > text_end) continue; /* turn lock prefix into DS segment override prefix */ - text_poke(*ptr, ((unsigned char []){0x3E}), 1); + if (**ptr == 0xf0) + text_poke(*ptr, ((unsigned char []){0x3E}), 1); }; mutex_unlock(&text_mutex); } -- 1.6.6.1.476.g01ddb ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [tip:x86/atomic] x86: Add support for lock prefix in alternatives 2010-02-24 9:54 ` [PATCH 1/4] x86: add support for lock prefix in alternatives (v2) Luca Barbieri @ 2010-02-26 5:12 ` tip-bot for Luca Barbieri 2010-04-29 23:24 ` [tip:x86/atomic] x86: Fix LOCK_PREFIX_HERE for uniprocessor build tip-bot for H. Peter Anvin 1 sibling, 0 replies; 11+ messages in thread From: tip-bot for Luca Barbieri @ 2010-02-26 5:12 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, luca, tglx Commit-ID: b3ac891b67bd4b1fc728d1c784cad1212dea433d Gitweb: http://git.kernel.org/tip/b3ac891b67bd4b1fc728d1c784cad1212dea433d Author: Luca Barbieri <luca@luca-barbieri.com> AuthorDate: Wed, 24 Feb 2010 10:54:22 +0100 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Thu, 25 Feb 2010 20:46:23 -0800 x86: Add support for lock prefix in alternatives The current lock prefix UP/SMP alternative code doesn't allow LOCK_PREFIX to be used in alternatives code. This patch solves the problem by adding a new LOCK_PREFIX_ALTERNATIVE_PATCH macro that only records the lock prefix location but does not emit the prefix. The user of this macro can then start any alternative sequence with "lock" and have it UP/SMP patched. To make this work, the UP/SMP alternative code is changed to do the lock/DS prefix switching only if the byte actually contains a lock or DS prefix. Thus, if an alternative without the "lock" is selected, it will now do nothing instead of clobbering the code. Changes in v2: - Naming change - Change label to not conflict with alternatives Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267005265-27958-2-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> --- arch/x86/include/asm/alternative.h | 8 +++++--- arch/x86/kernel/alternative.c | 6 ++++-- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 3b5b828..55fee12 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -28,12 +28,14 @@ */ #ifdef CONFIG_SMP -#define LOCK_PREFIX \ +#define LOCK_PREFIX_HERE \ ".section .smp_locks,\"a\"\n" \ _ASM_ALIGN "\n" \ - _ASM_PTR "661f\n" /* address */ \ + _ASM_PTR "671f\n" /* address */ \ ".previous\n" \ - "661:\n\tlock; " + "671:" + +#define LOCK_PREFIX LOCK_PREFIX_HERE "\n\tlock; " #else /* ! CONFIG_SMP */ #define LOCK_PREFIX "" diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 2589ea4..80b222e 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -244,7 +244,8 @@ static void alternatives_smp_lock(u8 **start, u8 **end, u8 *text, u8 *text_end) if (*ptr > text_end) continue; /* turn DS segment override prefix into lock prefix */ - text_poke(*ptr, ((unsigned char []){0xf0}), 1); + if (**ptr == 0x3e) + text_poke(*ptr, ((unsigned char []){0xf0}), 1); }; mutex_unlock(&text_mutex); } @@ -263,7 +264,8 @@ static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end if (*ptr > text_end) continue; /* turn lock prefix into DS segment override prefix */ - text_poke(*ptr, ((unsigned char []){0x3E}), 1); + if (**ptr == 0xf0) + text_poke(*ptr, ((unsigned char []){0x3E}), 1); }; mutex_unlock(&text_mutex); } ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [tip:x86/atomic] x86: Fix LOCK_PREFIX_HERE for uniprocessor build 2010-02-24 9:54 ` [PATCH 1/4] x86: add support for lock prefix in alternatives (v2) Luca Barbieri 2010-02-26 5:12 ` [tip:x86/atomic] x86: Add support for lock prefix in alternatives tip-bot for Luca Barbieri @ 2010-04-29 23:24 ` tip-bot for H. Peter Anvin 1 sibling, 0 replies; 11+ messages in thread From: tip-bot for H. Peter Anvin @ 2010-04-29 23:24 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, luca, tglx Commit-ID: b701a47ba48b698976fb2fe05fb285b0edc1d26a Gitweb: http://git.kernel.org/tip/b701a47ba48b698976fb2fe05fb285b0edc1d26a Author: H. Peter Anvin <hpa@zytor.com> AuthorDate: Thu, 29 Apr 2010 16:03:57 -0700 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Thu, 29 Apr 2010 16:08:54 -0700 x86: Fix LOCK_PREFIX_HERE for uniprocessor build Checkin b3ac891b67bd4b1fc728d1c784cad1212dea433d: x86: Add support for lock prefix in alternatives ... did not define LOCK_PREFIX_HERE in the case of a uniprocessor build. As a result, it would cause any of the usages of this macro to fail on a uniprocessor build. Fix this by defining LOCK_PREFIX_HERE as a null string. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267005265-27958-2-git-send-email-luca@luca-barbieri.com> --- arch/x86/include/asm/alternative.h | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 55fee12..e29a6c9 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -38,6 +38,7 @@ #define LOCK_PREFIX LOCK_PREFIX_HERE "\n\tlock; " #else /* ! CONFIG_SMP */ +#define LOCK_PREFIX_HERE "" #define LOCK_PREFIX "" #endif ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH 2/4] x86-32: allow UP/SMP lock replacement in cmpxchg64 (v2) 2010-02-24 9:54 [PATCH 0/4] x86-32: improve atomic64_t functions (v3, for tip/x86/asm) Luca Barbieri 2010-02-24 9:54 ` [PATCH 1/4] x86: add support for lock prefix in alternatives (v2) Luca Barbieri @ 2010-02-24 9:54 ` Luca Barbieri 2010-02-26 5:12 ` [tip:x86/atomic] x86-32: Allow UP/SMP lock replacement in cmpxchg64 tip-bot for Luca Barbieri 2010-02-24 9:54 ` [PATCH 3/4] lib: add self-test for atomic64_t Luca Barbieri 2010-02-24 9:54 ` [PATCH 4/4] x86-32: rewrite 32-bit atomic64 functions in assembly (v3) Luca Barbieri 3 siblings, 1 reply; 11+ messages in thread From: Luca Barbieri @ 2010-02-24 9:54 UTC (permalink / raw) To: hpa; +Cc: mingo, a.p.zijlstra, akpm, linux-kernel, Luca Barbieri Changes in v2: - Naming change Use the functionality just introduced in the previous patch. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> --- arch/x86/include/asm/cmpxchg_32.h | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h index ffb9bb6..8859e12 100644 --- a/arch/x86/include/asm/cmpxchg_32.h +++ b/arch/x86/include/asm/cmpxchg_32.h @@ -271,7 +271,8 @@ extern unsigned long long cmpxchg_486_u64(volatile void *, u64, u64); __typeof__(*(ptr)) __ret; \ __typeof__(*(ptr)) __old = (o); \ __typeof__(*(ptr)) __new = (n); \ - alternative_io("call cmpxchg8b_emu", \ + alternative_io(LOCK_PREFIX_HERE \ + "call cmpxchg8b_emu", \ "lock; cmpxchg8b (%%esi)" , \ X86_FEATURE_CX8, \ "=A" (__ret), \ -- 1.6.6.1.476.g01ddb ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [tip:x86/atomic] x86-32: Allow UP/SMP lock replacement in cmpxchg64 2010-02-24 9:54 ` [PATCH 2/4] x86-32: allow UP/SMP lock replacement in cmpxchg64 (v2) Luca Barbieri @ 2010-02-26 5:12 ` tip-bot for Luca Barbieri 0 siblings, 0 replies; 11+ messages in thread From: tip-bot for Luca Barbieri @ 2010-02-26 5:12 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, luca, tglx Commit-ID: 9c76b38476b18c45f97098a10b0176b321eba3ea Gitweb: http://git.kernel.org/tip/9c76b38476b18c45f97098a10b0176b321eba3ea Author: Luca Barbieri <luca@luca-barbieri.com> AuthorDate: Wed, 24 Feb 2010 10:54:23 +0100 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Thu, 25 Feb 2010 20:47:03 -0800 x86-32: Allow UP/SMP lock replacement in cmpxchg64 Use the functionality just introduced in the previous patch: mark the lock prefixes in cmpxchg64 alternatives for UP removal. Changes in v2: - Naming change Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267005265-27958-3-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> --- arch/x86/include/asm/cmpxchg_32.h | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h index ffb9bb6..8859e12 100644 --- a/arch/x86/include/asm/cmpxchg_32.h +++ b/arch/x86/include/asm/cmpxchg_32.h @@ -271,7 +271,8 @@ extern unsigned long long cmpxchg_486_u64(volatile void *, u64, u64); __typeof__(*(ptr)) __ret; \ __typeof__(*(ptr)) __old = (o); \ __typeof__(*(ptr)) __new = (n); \ - alternative_io("call cmpxchg8b_emu", \ + alternative_io(LOCK_PREFIX_HERE \ + "call cmpxchg8b_emu", \ "lock; cmpxchg8b (%%esi)" , \ X86_FEATURE_CX8, \ "=A" (__ret), \ ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH 3/4] lib: add self-test for atomic64_t 2010-02-24 9:54 [PATCH 0/4] x86-32: improve atomic64_t functions (v3, for tip/x86/asm) Luca Barbieri 2010-02-24 9:54 ` [PATCH 1/4] x86: add support for lock prefix in alternatives (v2) Luca Barbieri 2010-02-24 9:54 ` [PATCH 2/4] x86-32: allow UP/SMP lock replacement in cmpxchg64 (v2) Luca Barbieri @ 2010-02-24 9:54 ` Luca Barbieri 2010-02-26 5:13 ` [tip:x86/atomic] lib: Add " tip-bot for Luca Barbieri 2010-03-01 19:59 ` [tip:x86/atomic] x86, atomic64: In selftest, distinguish x86-64 from 586+ tip-bot for H. Peter Anvin 2010-02-24 9:54 ` [PATCH 4/4] x86-32: rewrite 32-bit atomic64 functions in assembly (v3) Luca Barbieri 3 siblings, 2 replies; 11+ messages in thread From: Luca Barbieri @ 2010-02-24 9:54 UTC (permalink / raw) To: hpa; +Cc: mingo, a.p.zijlstra, akpm, linux-kernel, Luca Barbieri [-- Warning: decoded text below may be mangled, UTF-8 assumed --] [-- Attachment #1: Type: text/plain, Size: 4798 bytes --] This patch adds self-test on boot code for atomic64_t. This has been used to test the later changes in this patchset. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> --- lib/Kconfig.debug | 7 ++ lib/Makefile | 2 + lib/atomic64_test.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 167 insertions(+), 0 deletions(-) create mode 100644 lib/atomic64_test.c diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 25c3ed5..3676c51 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1054,6 +1054,13 @@ config DMA_API_DEBUG This option causes a performance degredation. Use only if you want to debug device drivers. If unsure, say N. +config ATOMIC64_SELFTEST + bool "Perform an atomic64_t self-test at boot" + help + Enable this option to test the atomic64_t functions at boot. + + If unsure, say N. + source "samples/Kconfig" source "lib/Kconfig.kgdb" diff --git a/lib/Makefile b/lib/Makefile index 347ad8d..4af4786 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -99,6 +99,8 @@ obj-$(CONFIG_GENERIC_CSUM) += checksum.o obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o +obj-$(CONFIG_ATOMIC64_SELFTEST) += atomic64_test.o + hostprogs-y := gen_crc32table clean-files := crc32table.h diff --git a/lib/atomic64_test.c b/lib/atomic64_test.c new file mode 100644 index 0000000..4ff649e --- /dev/null +++ b/lib/atomic64_test.c @@ -0,0 +1,158 @@ +/* + * Testsuite for atomic64_t functions + * + * Copyright © 2010 Luca Barbieri + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ +#include <linux/init.h> +#include <asm/atomic.h> + +#define INIT(c) do { atomic64_set(&v, c); r = c; } while (0) +static __init int test_atomic64(void) +{ + long long v0 = 0xaaa31337c001d00dLL; + long long v1 = 0xdeadbeefdeafcafeLL; + long long v2 = 0xfaceabadf00df001LL; + long long onestwos = 0x1111111122222222LL; + long long one = 1LL; + + atomic64_t v = ATOMIC64_INIT(v0); + long long r = v0; + BUG_ON(v.counter != r); + + atomic64_set(&v, v1); + r = v1; + BUG_ON(v.counter != r); + BUG_ON(atomic64_read(&v) != r); + + INIT(v0); + atomic64_add(onestwos, &v); + r += onestwos; + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_add(-one, &v); + r += -one; + BUG_ON(v.counter != r); + + INIT(v0); + r += onestwos; + BUG_ON(atomic64_add_return(onestwos, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + r += -one; + BUG_ON(atomic64_add_return(-one, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_sub(onestwos, &v); + r -= onestwos; + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_sub(-one, &v); + r -= -one; + BUG_ON(v.counter != r); + + INIT(v0); + r -= onestwos; + BUG_ON(atomic64_sub_return(onestwos, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + r -= -one; + BUG_ON(atomic64_sub_return(-one, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_inc(&v); + r += one; + BUG_ON(v.counter != r); + + INIT(v0); + r += one; + BUG_ON(atomic64_inc_return(&v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_dec(&v); + r -= one; + BUG_ON(v.counter != r); + + INIT(v0); + r -= one; + BUG_ON(atomic64_dec_return(&v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_xchg(&v, v1) != v0); + r = v1; + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_cmpxchg(&v, v0, v1) != v0); + r = v1; + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_cmpxchg(&v, v2, v1) != v0); + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(!atomic64_add_unless(&v, one, v0)); + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_add_unless(&v, one, v1)); + r += one; + BUG_ON(v.counter != r); + + INIT(onestwos); + BUG_ON(atomic64_dec_if_positive(&v) != (onestwos - 1)); + r -= one; + BUG_ON(v.counter != r); + + INIT(0); + BUG_ON(atomic64_dec_if_positive(&v) != -one); + BUG_ON(v.counter != r); + + INIT(-one); + BUG_ON(atomic64_dec_if_positive(&v) != (-one - one)); + BUG_ON(v.counter != r); + + INIT(onestwos); + BUG_ON(atomic64_inc_not_zero(&v)); + r += one; + BUG_ON(v.counter != r); + + INIT(0); + BUG_ON(!atomic64_inc_not_zero(&v)); + BUG_ON(v.counter != r); + + INIT(-one); + BUG_ON(atomic64_inc_not_zero(&v)); + r += one; + BUG_ON(v.counter != r); + +#ifdef CONFIG_X86 + printk(KERN_INFO "atomic64 test passed for %s+ platform %s CX8 and %s SSE\n", +#ifdef CONFIG_X86_CMPXCHG64 + "586", +#else + "386", +#endif + boot_cpu_has(X86_FEATURE_CX8) ? "with" : "without", + boot_cpu_has(X86_FEATURE_XMM) ? "with" : "without"); +#else + printk(KERN_INFO "atomic64 test passed\n"); +#endif + + return 0; +} + +core_initcall(test_atomic64); -- 1.6.6.1.476.g01ddb ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [tip:x86/atomic] lib: Add self-test for atomic64_t 2010-02-24 9:54 ` [PATCH 3/4] lib: add self-test for atomic64_t Luca Barbieri @ 2010-02-26 5:13 ` tip-bot for Luca Barbieri 2010-03-01 19:59 ` [tip:x86/atomic] x86, atomic64: In selftest, distinguish x86-64 from 586+ tip-bot for H. Peter Anvin 1 sibling, 0 replies; 11+ messages in thread From: tip-bot for Luca Barbieri @ 2010-02-26 5:13 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, luca, tglx Commit-ID: 86a8938078a8bb518c5376de493e348c7490d506 Gitweb: http://git.kernel.org/tip/86a8938078a8bb518c5376de493e348c7490d506 Author: Luca Barbieri <luca@luca-barbieri.com> AuthorDate: Wed, 24 Feb 2010 10:54:24 +0100 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Thu, 25 Feb 2010 20:47:12 -0800 lib: Add self-test for atomic64_t This patch adds self-test on boot code for atomic64_t. This has been used to test the later changes in this patchset. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267005265-27958-4-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> --- lib/Kconfig.debug | 7 ++ lib/Makefile | 2 + lib/atomic64_test.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 167 insertions(+), 0 deletions(-) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 25c3ed5..3676c51 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1054,6 +1054,13 @@ config DMA_API_DEBUG This option causes a performance degredation. Use only if you want to debug device drivers. If unsure, say N. +config ATOMIC64_SELFTEST + bool "Perform an atomic64_t self-test at boot" + help + Enable this option to test the atomic64_t functions at boot. + + If unsure, say N. + source "samples/Kconfig" source "lib/Kconfig.kgdb" diff --git a/lib/Makefile b/lib/Makefile index 347ad8d..4af4786 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -99,6 +99,8 @@ obj-$(CONFIG_GENERIC_CSUM) += checksum.o obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o +obj-$(CONFIG_ATOMIC64_SELFTEST) += atomic64_test.o + hostprogs-y := gen_crc32table clean-files := crc32table.h diff --git a/lib/atomic64_test.c b/lib/atomic64_test.c new file mode 100644 index 0000000..4ff649e --- /dev/null +++ b/lib/atomic64_test.c @@ -0,0 +1,158 @@ +/* + * Testsuite for atomic64_t functions + * + * Copyright © 2010 Luca Barbieri + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ +#include <linux/init.h> +#include <asm/atomic.h> + +#define INIT(c) do { atomic64_set(&v, c); r = c; } while (0) +static __init int test_atomic64(void) +{ + long long v0 = 0xaaa31337c001d00dLL; + long long v1 = 0xdeadbeefdeafcafeLL; + long long v2 = 0xfaceabadf00df001LL; + long long onestwos = 0x1111111122222222LL; + long long one = 1LL; + + atomic64_t v = ATOMIC64_INIT(v0); + long long r = v0; + BUG_ON(v.counter != r); + + atomic64_set(&v, v1); + r = v1; + BUG_ON(v.counter != r); + BUG_ON(atomic64_read(&v) != r); + + INIT(v0); + atomic64_add(onestwos, &v); + r += onestwos; + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_add(-one, &v); + r += -one; + BUG_ON(v.counter != r); + + INIT(v0); + r += onestwos; + BUG_ON(atomic64_add_return(onestwos, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + r += -one; + BUG_ON(atomic64_add_return(-one, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_sub(onestwos, &v); + r -= onestwos; + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_sub(-one, &v); + r -= -one; + BUG_ON(v.counter != r); + + INIT(v0); + r -= onestwos; + BUG_ON(atomic64_sub_return(onestwos, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + r -= -one; + BUG_ON(atomic64_sub_return(-one, &v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_inc(&v); + r += one; + BUG_ON(v.counter != r); + + INIT(v0); + r += one; + BUG_ON(atomic64_inc_return(&v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + atomic64_dec(&v); + r -= one; + BUG_ON(v.counter != r); + + INIT(v0); + r -= one; + BUG_ON(atomic64_dec_return(&v) != r); + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_xchg(&v, v1) != v0); + r = v1; + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_cmpxchg(&v, v0, v1) != v0); + r = v1; + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_cmpxchg(&v, v2, v1) != v0); + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(!atomic64_add_unless(&v, one, v0)); + BUG_ON(v.counter != r); + + INIT(v0); + BUG_ON(atomic64_add_unless(&v, one, v1)); + r += one; + BUG_ON(v.counter != r); + + INIT(onestwos); + BUG_ON(atomic64_dec_if_positive(&v) != (onestwos - 1)); + r -= one; + BUG_ON(v.counter != r); + + INIT(0); + BUG_ON(atomic64_dec_if_positive(&v) != -one); + BUG_ON(v.counter != r); + + INIT(-one); + BUG_ON(atomic64_dec_if_positive(&v) != (-one - one)); + BUG_ON(v.counter != r); + + INIT(onestwos); + BUG_ON(atomic64_inc_not_zero(&v)); + r += one; + BUG_ON(v.counter != r); + + INIT(0); + BUG_ON(!atomic64_inc_not_zero(&v)); + BUG_ON(v.counter != r); + + INIT(-one); + BUG_ON(atomic64_inc_not_zero(&v)); + r += one; + BUG_ON(v.counter != r); + +#ifdef CONFIG_X86 + printk(KERN_INFO "atomic64 test passed for %s+ platform %s CX8 and %s SSE\n", +#ifdef CONFIG_X86_CMPXCHG64 + "586", +#else + "386", +#endif + boot_cpu_has(X86_FEATURE_CX8) ? "with" : "without", + boot_cpu_has(X86_FEATURE_XMM) ? "with" : "without"); +#else + printk(KERN_INFO "atomic64 test passed\n"); +#endif + + return 0; +} + +core_initcall(test_atomic64); ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [tip:x86/atomic] x86, atomic64: In selftest, distinguish x86-64 from 586+ 2010-02-24 9:54 ` [PATCH 3/4] lib: add self-test for atomic64_t Luca Barbieri 2010-02-26 5:13 ` [tip:x86/atomic] lib: Add " tip-bot for Luca Barbieri @ 2010-03-01 19:59 ` tip-bot for H. Peter Anvin 1 sibling, 0 replies; 11+ messages in thread From: tip-bot for H. Peter Anvin @ 2010-03-01 19:59 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, luca, tglx Commit-ID: a5c9161f27c3e1ae6c0094d262f03a7e98262181 Gitweb: http://git.kernel.org/tip/a5c9161f27c3e1ae6c0094d262f03a7e98262181 Author: H. Peter Anvin <hpa@zytor.com> AuthorDate: Mon, 1 Mar 2010 11:49:23 -0800 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Mon, 1 Mar 2010 11:51:56 -0800 x86, atomic64: In selftest, distinguish x86-64 from 586+ The x86-64 implementation of the atomics is totally different from the i586+ implementation, which makes it quite confusing to call it "586+". Also fix indentation, and add "i" for "i386" and "i586" as used elsewhere in the kernel. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267005265-27958-4-git-send-email-luca@luca-barbieri.com> --- lib/atomic64_test.c | 14 ++++++++------ 1 files changed, 8 insertions(+), 6 deletions(-) diff --git a/lib/atomic64_test.c b/lib/atomic64_test.c index f7bb706..65e482c 100644 --- a/lib/atomic64_test.c +++ b/lib/atomic64_test.c @@ -144,14 +144,16 @@ static __init int test_atomic64(void) BUG_ON(v.counter != r); #ifdef CONFIG_X86 - printk(KERN_INFO "atomic64 test passed for %s+ platform %s CX8 and %s SSE\n", -#ifdef CONFIG_X86_CMPXCHG64 - "586", + printk(KERN_INFO "atomic64 test passed for %s platform %s CX8 and %s SSE\n", +#ifdef CONFIG_X86_64 + "x86-64", +#elif defined(CONFIG_X86_CMPXCHG64) + "i586+", #else - "386", + "i386+", #endif - boot_cpu_has(X86_FEATURE_CX8) ? "with" : "without", - boot_cpu_has(X86_FEATURE_XMM) ? "with" : "without"); + boot_cpu_has(X86_FEATURE_CX8) ? "with" : "without", + boot_cpu_has(X86_FEATURE_XMM) ? "with" : "without"); #else printk(KERN_INFO "atomic64 test passed\n"); #endif ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH 4/4] x86-32: rewrite 32-bit atomic64 functions in assembly (v3) 2010-02-24 9:54 [PATCH 0/4] x86-32: improve atomic64_t functions (v3, for tip/x86/asm) Luca Barbieri ` (2 preceding siblings ...) 2010-02-24 9:54 ` [PATCH 3/4] lib: add self-test for atomic64_t Luca Barbieri @ 2010-02-24 9:54 ` Luca Barbieri 2010-02-26 5:13 ` [tip:x86/atomic] x86-32: Rewrite 32-bit atomic64 functions in assembly tip-bot for Luca Barbieri 3 siblings, 1 reply; 11+ messages in thread From: Luca Barbieri @ 2010-02-24 9:54 UTC (permalink / raw) To: hpa; +Cc: mingo, a.p.zijlstra, akpm, linux-kernel, Luca Barbieri [-- Warning: decoded text below may be mangled, UTF-8 assumed --] [-- Attachment #1: Type: text/plain, Size: 27245 bytes --] 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 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 Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> --- arch/x86/include/asm/atomic64_32.h | 278 +++++++++++++++++++++++++++--------- arch/x86/lib/Makefile | 3 +- arch/x86/lib/atomic64_32.c | 273 +++++++---------------------------- arch/x86/lib/atomic64_386_32.S | 175 ++++++++++++++++++++++ arch/x86/lib/atomic64_cx8_32.S | 225 +++++++++++++++++++++++++++++ 5 files changed, 664 insertions(+), 290 deletions(-) create mode 100644 arch/x86/lib/atomic64_386_32.S create mode 100644 arch/x86/lib/atomic64_cx8_32.S diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h index 03027bf..2a934aa 100644 --- a/arch/x86/include/asm/atomic64_32.h +++ b/arch/x86/include/asm/atomic64_32.h @@ -14,109 +14,193 @@ typedef struct { #define ATOMIC64_INIT(val) { (val) } -extern u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val); +#ifdef CONFIG_X86_CMPXCHG64 +#define ATOMIC64_ALTERNATIVE_(f, g) "call atomic64_" #g "_cx8" +#else +#define ATOMIC64_ALTERNATIVE_(f, g) ALTERNATIVE("call atomic64_" #f "_386", "call atomic64_" #g "_cx8", X86_FEATURE_CX8) +#endif + +#define ATOMIC64_ALTERNATIVE(f) ATOMIC64_ALTERNATIVE_(f, f) + +/** + * atomic64_cmpxchg - cmpxchg atomic64 variable + * @p: pointer to type atomic64_t + * @o: expected value + * @n: new value + * + * Atomically sets @v to @n if it was equal to @o and returns + * the old value. + */ + +static inline long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n) +{ + return cmpxchg64(&v->counter, o, n); +} /** * atomic64_xchg - xchg atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign + * @v: pointer to type atomic64_t + * @n: value to assign * - * Atomically xchgs the value of @ptr to @new_val and returns + * Atomically xchgs the value of @v to @n and returns * the old value. */ -extern u64 atomic64_xchg(atomic64_t *ptr, u64 new_val); +static inline long long atomic64_xchg(atomic64_t *v, long long n) +{ + long long o; + unsigned high = (unsigned)(n >> 32); + unsigned low = (unsigned)n; + asm volatile(ATOMIC64_ALTERNATIVE(xchg) + : "=A" (o), "+b" (low), "+c" (high) + : "S" (v) + : "memory" + ); + return o; +} /** * atomic64_set - set atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign + * @v: pointer to type atomic64_t + * @n: value to assign * - * Atomically sets the value of @ptr to @new_val. + * Atomically sets the value of @v to @n. */ -extern void atomic64_set(atomic64_t *ptr, u64 new_val); +static inline void atomic64_set(atomic64_t *v, long long i) +{ + unsigned high = (unsigned)(i >> 32); + unsigned low = (unsigned)i; + asm volatile(ATOMIC64_ALTERNATIVE(set) + : "+b" (low), "+c" (high) + : "S" (v) + : "eax", "edx", "memory" + ); +} /** * atomic64_read - read atomic64 variable - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically reads the value of @ptr and returns it. + * Atomically reads the value of @v and returns it. */ -static inline u64 atomic64_read(atomic64_t *ptr) +static inline long long atomic64_read(atomic64_t *v) { - u64 res; - - /* - * Note, we inline this atomic64_t primitive because - * it only clobbers EAX/EDX and leaves the others - * untouched. We also (somewhat subtly) rely on the - * fact that cmpxchg8b returns the current 64-bit value - * of the memory location we are touching: - */ - asm volatile( - "mov %%ebx, %%eax\n\t" - "mov %%ecx, %%edx\n\t" - LOCK_PREFIX "cmpxchg8b %1\n" - : "=&A" (res) - : "m" (*ptr) - ); - - return res; -} - -extern u64 atomic64_read(atomic64_t *ptr); + long long r; + asm volatile(ATOMIC64_ALTERNATIVE(read) + : "=A" (r), "+c" (v) + : : "memory" + ); + return r; + } /** * atomic64_add_return - add and return - * @delta: integer value to add - * @ptr: pointer to type atomic64_t + * @i: integer value to add + * @v: pointer to type atomic64_t * - * Atomically adds @delta to @ptr and returns @delta + *@ptr + * Atomically adds @i to @v and returns @i + *@v */ -extern u64 atomic64_add_return(u64 delta, atomic64_t *ptr); +static inline long long atomic64_add_return(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE(add_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} /* * Other variants with different arithmetic operators: */ -extern u64 atomic64_sub_return(u64 delta, atomic64_t *ptr); -extern u64 atomic64_inc_return(atomic64_t *ptr); -extern u64 atomic64_dec_return(atomic64_t *ptr); +static inline long long atomic64_sub_return(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE(sub_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} + +static inline long long atomic64_inc_return(atomic64_t *v) +{ + long long a; + asm volatile(ATOMIC64_ALTERNATIVE(inc_return) + : "=A" (a) + : "S" (v) + : "memory", "ecx" + ); + return a; +} + +static inline long long atomic64_dec_return(atomic64_t *v) +{ + long long a; + asm volatile(ATOMIC64_ALTERNATIVE(dec_return) + : "=A" (a) + : "S" (v) + : "memory", "ecx" + ); + return a; +} /** * atomic64_add - add integer to atomic64 variable - * @delta: integer value to add - * @ptr: pointer to type atomic64_t + * @i: integer value to add + * @v: pointer to type atomic64_t * - * Atomically adds @delta to @ptr. + * Atomically adds @i to @v. */ -extern void atomic64_add(u64 delta, atomic64_t *ptr); +static inline long long atomic64_add(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(add, add_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} /** * atomic64_sub - subtract the atomic64 variable - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t + * @i: integer value to subtract + * @v: pointer to type atomic64_t * - * Atomically subtracts @delta from @ptr. + * Atomically subtracts @i from @v. */ -extern void atomic64_sub(u64 delta, atomic64_t *ptr); +static inline long long atomic64_sub(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(sub, sub_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} /** * atomic64_sub_and_test - subtract value from variable and test result - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t - * - * Atomically subtracts @delta from @ptr and returns + * @i: integer value to subtract + * @v: pointer to type atomic64_t + * + * Atomically subtracts @i from @v and returns * true if the result is zero, or false for all * other cases. */ -extern int atomic64_sub_and_test(u64 delta, atomic64_t *ptr); +static inline int atomic64_sub_and_test(long long i, atomic64_t *v) +{ + return atomic64_sub_return(i, v) == 0; +} /** * atomic64_inc - increment atomic64 variable - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically increments @ptr by 1. + * Atomically increments @v by 1. */ -extern void atomic64_inc(atomic64_t *ptr); +static inline void atomic64_inc(atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(inc, inc_return) + : : "S" (v) + : "memory", "eax", "ecx", "edx" + ); +} /** * atomic64_dec - decrement atomic64 variable @@ -124,37 +208,97 @@ extern void atomic64_inc(atomic64_t *ptr); * * Atomically decrements @ptr by 1. */ -extern void atomic64_dec(atomic64_t *ptr); +static inline void atomic64_dec(atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(dec, dec_return) + : : "S" (v) + : "memory", "eax", "ecx", "edx" + ); +} /** * atomic64_dec_and_test - decrement and test - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically decrements @ptr by 1 and + * Atomically decrements @v by 1 and * returns true if the result is 0, or false for all other * cases. */ -extern int atomic64_dec_and_test(atomic64_t *ptr); +static inline int atomic64_dec_and_test(atomic64_t *v) +{ + return atomic64_dec_return(v) == 0; +} /** * atomic64_inc_and_test - increment and test - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically increments @ptr by 1 + * Atomically increments @v by 1 * and returns true if the result is zero, or false for all * other cases. */ -extern int atomic64_inc_and_test(atomic64_t *ptr); +static inline int atomic64_inc_and_test(atomic64_t *v) +{ + return atomic64_inc_return(v) == 0; +} /** * atomic64_add_negative - add and test if negative - * @delta: integer value to add - * @ptr: pointer to type atomic64_t + * @i: integer value to add + * @v: pointer to type atomic64_t * - * Atomically adds @delta to @ptr and returns true + * Atomically adds @i to @v and returns true * if the result is negative, or false when * result is greater than or equal to zero. */ -extern int atomic64_add_negative(u64 delta, atomic64_t *ptr); +static inline int atomic64_add_negative(long long i, atomic64_t *v) +{ + return atomic64_add_return(i, v) < 0; +} + +/** + * atomic64_add_unless - add unless the number is a given value + * @v: pointer of type atomic64_t + * @a: the amount to add to v... + * @u: ...unless v is equal to u. + * + * Atomically adds @a to @v, so long as it was not @u. + * Returns non-zero if @v was not @u, and zero otherwise. + */ +static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u) +{ + unsigned low = (unsigned)u; + unsigned high = (unsigned)(u >> 32); + asm volatile(ATOMIC64_ALTERNATIVE(add_unless) "\n\t" + : "+A" (a), "+c" (v), "+S" (low), "+D" (high) + : : "memory"); + return (int)a; +} + + +static inline int atomic64_inc_not_zero(atomic64_t *v) +{ + int r; + asm volatile(ATOMIC64_ALTERNATIVE(inc_not_zero) + : "=a" (r) + : "S" (v) + : "ecx", "edx", "memory" + ); + return r; +} + +static inline long long atomic64_dec_if_positive(atomic64_t *v) +{ + long long r; + asm volatile(ATOMIC64_ALTERNATIVE(dec_if_positive) + : "=A" (r) + : "S" (v) + : "ecx", "memory" + ); + return r; +} + +#undef ATOMIC64_ALTERNATIVE +#undef ATOMIC64_ALTERNATIVE_ #endif /* _ASM_X86_ATOMIC64_32_H */ diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index cffd754..05d686b 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -26,11 +26,12 @@ obj-y += msr.o msr-reg.o msr-reg-export.o ifeq ($(CONFIG_X86_32),y) obj-y += atomic64_32.o + lib-y += atomic64_cx8_32.o lib-y += checksum_32.o lib-y += strstr_32.o lib-y += semaphore_32.o string_32.o ifneq ($(CONFIG_X86_CMPXCHG64),y) - lib-y += cmpxchg8b_emu.o + lib-y += cmpxchg8b_emu.o atomic64_386_32.o endif lib-$(CONFIG_X86_USE_3DNOW) += mmx_32.o else diff --git a/arch/x86/lib/atomic64_32.c b/arch/x86/lib/atomic64_32.c index 824fa0b..540179e 100644 --- a/arch/x86/lib/atomic64_32.c +++ b/arch/x86/lib/atomic64_32.c @@ -6,225 +6,54 @@ #include <asm/cmpxchg.h> #include <asm/atomic.h> -static noinline u64 cmpxchg8b(u64 *ptr, u64 old, u64 new) -{ - u32 low = new; - u32 high = new >> 32; - - asm volatile( - LOCK_PREFIX "cmpxchg8b %1\n" - : "+A" (old), "+m" (*ptr) - : "b" (low), "c" (high) - ); - return old; -} - -u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val) -{ - return cmpxchg8b(&ptr->counter, old_val, new_val); -} -EXPORT_SYMBOL(atomic64_cmpxchg); - -/** - * atomic64_xchg - xchg atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign - * - * Atomically xchgs the value of @ptr to @new_val and returns - * the old value. - */ -u64 atomic64_xchg(atomic64_t *ptr, u64 new_val) -{ - /* - * Try first with a (possibly incorrect) assumption about - * what we have there. We'll do two loops most likely, - * but we'll get an ownership MESI transaction straight away - * instead of a read transaction followed by a - * flush-for-ownership transaction: - */ - u64 old_val, real_val = 0; - - do { - old_val = real_val; - - real_val = atomic64_cmpxchg(ptr, old_val, new_val); - - } while (real_val != old_val); - - return old_val; -} -EXPORT_SYMBOL(atomic64_xchg); - -/** - * atomic64_set - set atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign - * - * Atomically sets the value of @ptr to @new_val. - */ -void atomic64_set(atomic64_t *ptr, u64 new_val) -{ - atomic64_xchg(ptr, new_val); -} -EXPORT_SYMBOL(atomic64_set); - -/** -EXPORT_SYMBOL(atomic64_read); - * atomic64_add_return - add and return - * @delta: integer value to add - * @ptr: pointer to type atomic64_t - * - * Atomically adds @delta to @ptr and returns @delta + *@ptr - */ -noinline u64 atomic64_add_return(u64 delta, atomic64_t *ptr) -{ - /* - * Try first with a (possibly incorrect) assumption about - * what we have there. We'll do two loops most likely, - * but we'll get an ownership MESI transaction straight away - * instead of a read transaction followed by a - * flush-for-ownership transaction: - */ - u64 old_val, new_val, real_val = 0; - - do { - old_val = real_val; - new_val = old_val + delta; - - real_val = atomic64_cmpxchg(ptr, old_val, new_val); - - } while (real_val != old_val); - - return new_val; -} -EXPORT_SYMBOL(atomic64_add_return); - -u64 atomic64_sub_return(u64 delta, atomic64_t *ptr) -{ - return atomic64_add_return(-delta, ptr); -} -EXPORT_SYMBOL(atomic64_sub_return); - -u64 atomic64_inc_return(atomic64_t *ptr) -{ - return atomic64_add_return(1, ptr); -} -EXPORT_SYMBOL(atomic64_inc_return); - -u64 atomic64_dec_return(atomic64_t *ptr) -{ - return atomic64_sub_return(1, ptr); -} -EXPORT_SYMBOL(atomic64_dec_return); - -/** - * atomic64_add - add integer to atomic64 variable - * @delta: integer value to add - * @ptr: pointer to type atomic64_t - * - * Atomically adds @delta to @ptr. - */ -void atomic64_add(u64 delta, atomic64_t *ptr) -{ - atomic64_add_return(delta, ptr); -} -EXPORT_SYMBOL(atomic64_add); - -/** - * atomic64_sub - subtract the atomic64 variable - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t - * - * Atomically subtracts @delta from @ptr. - */ -void atomic64_sub(u64 delta, atomic64_t *ptr) -{ - atomic64_add(-delta, ptr); -} -EXPORT_SYMBOL(atomic64_sub); - -/** - * atomic64_sub_and_test - subtract value from variable and test result - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t - * - * Atomically subtracts @delta from @ptr and returns - * true if the result is zero, or false for all - * other cases. - */ -int atomic64_sub_and_test(u64 delta, atomic64_t *ptr) -{ - u64 new_val = atomic64_sub_return(delta, ptr); - - return new_val == 0; -} -EXPORT_SYMBOL(atomic64_sub_and_test); - -/** - * atomic64_inc - increment atomic64 variable - * @ptr: pointer to type atomic64_t - * - * Atomically increments @ptr by 1. - */ -void atomic64_inc(atomic64_t *ptr) -{ - atomic64_add(1, ptr); -} -EXPORT_SYMBOL(atomic64_inc); - -/** - * atomic64_dec - decrement atomic64 variable - * @ptr: pointer to type atomic64_t - * - * Atomically decrements @ptr by 1. - */ -void atomic64_dec(atomic64_t *ptr) -{ - atomic64_sub(1, ptr); -} -EXPORT_SYMBOL(atomic64_dec); - -/** - * atomic64_dec_and_test - decrement and test - * @ptr: pointer to type atomic64_t - * - * Atomically decrements @ptr by 1 and - * returns true if the result is 0, or false for all other - * cases. - */ -int atomic64_dec_and_test(atomic64_t *ptr) -{ - return atomic64_sub_and_test(1, ptr); -} -EXPORT_SYMBOL(atomic64_dec_and_test); - -/** - * atomic64_inc_and_test - increment and test - * @ptr: pointer to type atomic64_t - * - * Atomically increments @ptr by 1 - * and returns true if the result is zero, or false for all - * other cases. - */ -int atomic64_inc_and_test(atomic64_t *ptr) -{ - return atomic64_sub_and_test(-1, ptr); -} -EXPORT_SYMBOL(atomic64_inc_and_test); - -/** - * atomic64_add_negative - add and test if negative - * @delta: integer value to add - * @ptr: pointer to type atomic64_t - * - * Atomically adds @delta to @ptr and returns true - * if the result is negative, or false when - * result is greater than or equal to zero. - */ -int atomic64_add_negative(u64 delta, atomic64_t *ptr) -{ - s64 new_val = atomic64_add_return(delta, ptr); - - return new_val < 0; -} -EXPORT_SYMBOL(atomic64_add_negative); +long long atomic64_read_cx8(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_read_cx8); +long long atomic64_set_cx8(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_set_cx8); +long long atomic64_xchg_cx8(long long, unsigned high); +EXPORT_SYMBOL(atomic64_xchg_cx8); +long long atomic64_add_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_add_return_cx8); +long long atomic64_sub_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_sub_return_cx8); +long long atomic64_inc_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_return_cx8); +long long atomic64_dec_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_return_cx8); +long long atomic64_dec_if_positive_cx8(atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_if_positive_cx8); +int atomic64_inc_not_zero_cx8(atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_not_zero_cx8); +int atomic64_add_unless_cx8(atomic64_t *v, long long a, long long u); +EXPORT_SYMBOL(atomic64_add_unless_cx8); + +#ifndef CONFIG_X86_CMPXCHG64 +long long atomic64_read_386(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_read_386); +long long atomic64_set_386(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_set_386); +long long atomic64_xchg_386(long long, unsigned high); +EXPORT_SYMBOL(atomic64_xchg_386); +long long atomic64_add_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_add_return_386); +long long atomic64_sub_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_sub_return_386); +long long atomic64_inc_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_return_386); +long long atomic64_dec_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_return_386); +long long atomic64_add_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_add_386); +long long atomic64_sub_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_sub_386); +long long atomic64_inc_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_386); +long long atomic64_dec_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_386); +long long atomic64_dec_if_positive_386(atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_if_positive_386); +int atomic64_inc_not_zero_386(atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_not_zero_386); +int atomic64_add_unless_386(atomic64_t *v, long long a, long long u); +EXPORT_SYMBOL(atomic64_add_unless_386); +#endif diff --git a/arch/x86/lib/atomic64_386_32.S b/arch/x86/lib/atomic64_386_32.S new file mode 100644 index 0000000..5db07fe --- /dev/null +++ b/arch/x86/lib/atomic64_386_32.S @@ -0,0 +1,175 @@ +/* + * atomic64_t for 386/486 + * + * Copyright © 2010 Luca Barbieri + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/linkage.h> +#include <asm/alternative-asm.h> +#include <asm/dwarf2.h> + +/* if you want SMP support, implement these with real spinlocks */ +.macro LOCK reg + pushfl + CFI_ADJUST_CFA_OFFSET 4 + cli +.endm + +.macro UNLOCK reg + popfl + CFI_ADJUST_CFA_OFFSET -4 +.endm + +.macro BEGIN func reg +$v = \reg + +ENTRY(atomic64_\func\()_386) + CFI_STARTPROC + LOCK $v + +.macro RETURN + UNLOCK $v + ret +.endm + +.macro END_ + CFI_ENDPROC +ENDPROC(atomic64_\func\()_386) +.purgem RETURN +.purgem END_ +.purgem END +.endm + +.macro END +RETURN +END_ +.endm +.endm + +BEGIN read %ecx + movl ($v), %eax + movl 4($v), %edx +END + +BEGIN set %esi + movl %ebx, ($v) + movl %ecx, 4($v) +END + +BEGIN xchg %esi + movl ($v), %eax + movl 4($v), %edx + movl %ebx, ($v) + movl %ecx, 4($v) +END + +BEGIN add %ecx + addl %eax, ($v) + adcl %edx, 4($v) +END + +BEGIN add_return %ecx + addl ($v), %eax + adcl 4($v), %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN sub %ecx + subl %eax, ($v) + sbbl %edx, 4($v) +END + +BEGIN sub_return %ecx + negl %edx + negl %eax + sbbl $0, %edx + addl ($v), %eax + adcl 4($v), %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN inc %esi + addl $1, ($v) + adcl $0, 4($v) +END + +BEGIN inc_return %esi + movl ($v), %eax + movl 4($v), %edx + addl $1, %eax + adcl $0, %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN dec %esi + subl $1, ($v) + sbbl $0, 4($v) +END + +BEGIN dec_return %esi + movl ($v), %eax + movl 4($v), %edx + subl $1, %eax + sbbl $0, %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN add_unless %ecx + addl %eax, %esi + adcl %edx, %edi + addl ($v), %eax + adcl 4($v), %edx + cmpl %eax, %esi + je 3f +1: + movl %eax, ($v) + movl %edx, 4($v) + xorl %eax, %eax +2: +RETURN +3: + cmpl %edx, %edi + jne 1b + movl $1, %eax + jmp 2b +END_ + +BEGIN inc_not_zero %esi + movl ($v), %eax + movl 4($v), %edx + testl %eax, %eax + je 3f +1: + addl $1, %eax + adcl $0, %edx + movl %eax, ($v) + movl %edx, 4($v) + xorl %eax, %eax +2: +RETURN +3: + testl %edx, %edx + jne 1b + movl $1, %eax + jmp 2b +END_ + +BEGIN dec_if_positive %esi + movl ($v), %eax + movl 4($v), %edx + subl $1, %eax + sbbl $0, %edx + js 1f + movl %eax, ($v) + movl %edx, 4($v) +1: +END diff --git a/arch/x86/lib/atomic64_cx8_32.S b/arch/x86/lib/atomic64_cx8_32.S new file mode 100644 index 0000000..e49c4eb --- /dev/null +++ b/arch/x86/lib/atomic64_cx8_32.S @@ -0,0 +1,225 @@ +/* + * atomic64_t for 586+ + * + * Copyright © 2010 Luca Barbieri + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/linkage.h> +#include <asm/alternative-asm.h> +#include <asm/dwarf2.h> + +.macro SAVE reg + pushl %\reg + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET \reg, 0 +.endm + +.macro RESTORE reg + popl %\reg + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE \reg +.endm + +.macro read64 reg + movl %ebx, %eax + movl %ecx, %edx +/* we need LOCK_PREFIX since otherwise cmpxchg8b always does the write */ + LOCK_PREFIX + cmpxchg8b (\reg) +.endm + +ENTRY(atomic64_read_cx8) + CFI_STARTPROC + + read64 %ecx + ret + CFI_ENDPROC +ENDPROC(atomic64_read_cx8) + +ENTRY(atomic64_set_cx8) + CFI_STARTPROC + +1: +/* we don't need LOCK_PREFIX since aligned 64-bit writes + * are atomic on 586 and newer */ + cmpxchg8b (%esi) + jne 1b + + ret + CFI_ENDPROC +ENDPROC(atomic64_set_cx8) + +ENTRY(atomic64_xchg_cx8) + CFI_STARTPROC + + movl %ebx, %eax + movl %ecx, %edx +1: + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + + ret + CFI_ENDPROC +ENDPROC(atomic64_xchg_cx8) + +.macro addsub_return func ins insc +ENTRY(atomic64_\func\()_return_cx8) + CFI_STARTPROC + SAVE ebp + SAVE ebx + SAVE esi + SAVE edi + + movl %eax, %esi + movl %edx, %edi + movl %ecx, %ebp + + read64 %ebp +1: + movl %eax, %ebx + movl %edx, %ecx + \ins\()l %esi, %ebx + \insc\()l %edi, %ecx + LOCK_PREFIX + cmpxchg8b (%ebp) + jne 1b + +10: + movl %ebx, %eax + movl %ecx, %edx + RESTORE edi + RESTORE esi + RESTORE ebx + RESTORE ebp + ret + CFI_ENDPROC +ENDPROC(atomic64_\func\()_return_cx8) +.endm + +addsub_return add add adc +addsub_return sub sub sbb + +.macro incdec_return func ins insc +ENTRY(atomic64_\func\()_return_cx8) + CFI_STARTPROC + SAVE ebx + + read64 %esi +1: + movl %eax, %ebx + movl %edx, %ecx + \ins\()l $1, %ebx + \insc\()l $0, %ecx + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + +10: + movl %ebx, %eax + movl %ecx, %edx + RESTORE ebx + ret + CFI_ENDPROC +ENDPROC(atomic64_\func\()_return_cx8) +.endm + +incdec_return inc add adc +incdec_return dec sub sbb + +ENTRY(atomic64_dec_if_positive_cx8) + CFI_STARTPROC + SAVE ebx + + read64 %esi +1: + movl %eax, %ebx + movl %edx, %ecx + subl $1, %ebx + sbb $0, %ecx + js 2f + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + +2: + movl %ebx, %eax + movl %ecx, %edx + RESTORE ebx + ret + CFI_ENDPROC +ENDPROC(atomic64_dec_if_positive_cx8) + +ENTRY(atomic64_add_unless_cx8) + CFI_STARTPROC + SAVE ebp + SAVE ebx +/* these just push these two parameters on the stack */ + SAVE edi + SAVE esi + + movl %ecx, %ebp + movl %eax, %esi + movl %edx, %edi + + read64 %ebp +1: + cmpl %eax, 0(%esp) + je 4f +2: + movl %eax, %ebx + movl %edx, %ecx + addl %esi, %ebx + adcl %edi, %ecx + LOCK_PREFIX + cmpxchg8b (%ebp) + jne 1b + + xorl %eax, %eax +3: + addl $8, %esp + CFI_ADJUST_CFA_OFFSET -8 + RESTORE ebx + RESTORE ebp + ret +4: + cmpl %edx, 4(%esp) + jne 2b + movl $1, %eax + jmp 3b + CFI_ENDPROC +ENDPROC(atomic64_add_unless_cx8) + +ENTRY(atomic64_inc_not_zero_cx8) + CFI_STARTPROC + SAVE ebx + + read64 %esi +1: + testl %eax, %eax + je 4f +2: + movl %eax, %ebx + movl %edx, %ecx + addl $1, %ebx + adcl $0, %ecx + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + + xorl %eax, %eax +3: + RESTORE ebx + ret +4: + testl %edx, %edx + jne 2b + movl $1, %eax + jmp 3b + CFI_ENDPROC +ENDPROC(atomic64_inc_not_zero_cx8) -- 1.6.6.1.476.g01ddb ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [tip:x86/atomic] x86-32: Rewrite 32-bit atomic64 functions in assembly 2010-02-24 9:54 ` [PATCH 4/4] x86-32: rewrite 32-bit atomic64 functions in assembly (v3) Luca Barbieri @ 2010-02-26 5:13 ` tip-bot for Luca Barbieri 0 siblings, 0 replies; 11+ messages in thread From: tip-bot for Luca Barbieri @ 2010-02-26 5:13 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, luca, tglx Commit-ID: a7e926abc3adfbd2e5e20d2b46177adb4e313915 Gitweb: http://git.kernel.org/tip/a7e926abc3adfbd2e5e20d2b46177adb4e313915 Author: Luca Barbieri <luca@luca-barbieri.com> AuthorDate: Wed, 24 Feb 2010 10:54:25 +0100 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Thu, 25 Feb 2010 20:47:30 -0800 x86-32: Rewrite 32-bit atomic64 functions in assembly 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> --- arch/x86/include/asm/atomic64_32.h | 278 +++++++++++++++++++++++++++--------- arch/x86/lib/Makefile | 3 +- arch/x86/lib/atomic64_32.c | 273 +++++++---------------------------- arch/x86/lib/atomic64_386_32.S | 175 ++++++++++++++++++++++ arch/x86/lib/atomic64_cx8_32.S | 225 +++++++++++++++++++++++++++++ 5 files changed, 664 insertions(+), 290 deletions(-) diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h index 03027bf..2a934aa 100644 --- a/arch/x86/include/asm/atomic64_32.h +++ b/arch/x86/include/asm/atomic64_32.h @@ -14,109 +14,193 @@ typedef struct { #define ATOMIC64_INIT(val) { (val) } -extern u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val); +#ifdef CONFIG_X86_CMPXCHG64 +#define ATOMIC64_ALTERNATIVE_(f, g) "call atomic64_" #g "_cx8" +#else +#define ATOMIC64_ALTERNATIVE_(f, g) ALTERNATIVE("call atomic64_" #f "_386", "call atomic64_" #g "_cx8", X86_FEATURE_CX8) +#endif + +#define ATOMIC64_ALTERNATIVE(f) ATOMIC64_ALTERNATIVE_(f, f) + +/** + * atomic64_cmpxchg - cmpxchg atomic64 variable + * @p: pointer to type atomic64_t + * @o: expected value + * @n: new value + * + * Atomically sets @v to @n if it was equal to @o and returns + * the old value. + */ + +static inline long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n) +{ + return cmpxchg64(&v->counter, o, n); +} /** * atomic64_xchg - xchg atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign + * @v: pointer to type atomic64_t + * @n: value to assign * - * Atomically xchgs the value of @ptr to @new_val and returns + * Atomically xchgs the value of @v to @n and returns * the old value. */ -extern u64 atomic64_xchg(atomic64_t *ptr, u64 new_val); +static inline long long atomic64_xchg(atomic64_t *v, long long n) +{ + long long o; + unsigned high = (unsigned)(n >> 32); + unsigned low = (unsigned)n; + asm volatile(ATOMIC64_ALTERNATIVE(xchg) + : "=A" (o), "+b" (low), "+c" (high) + : "S" (v) + : "memory" + ); + return o; +} /** * atomic64_set - set atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign + * @v: pointer to type atomic64_t + * @n: value to assign * - * Atomically sets the value of @ptr to @new_val. + * Atomically sets the value of @v to @n. */ -extern void atomic64_set(atomic64_t *ptr, u64 new_val); +static inline void atomic64_set(atomic64_t *v, long long i) +{ + unsigned high = (unsigned)(i >> 32); + unsigned low = (unsigned)i; + asm volatile(ATOMIC64_ALTERNATIVE(set) + : "+b" (low), "+c" (high) + : "S" (v) + : "eax", "edx", "memory" + ); +} /** * atomic64_read - read atomic64 variable - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically reads the value of @ptr and returns it. + * Atomically reads the value of @v and returns it. */ -static inline u64 atomic64_read(atomic64_t *ptr) +static inline long long atomic64_read(atomic64_t *v) { - u64 res; - - /* - * Note, we inline this atomic64_t primitive because - * it only clobbers EAX/EDX and leaves the others - * untouched. We also (somewhat subtly) rely on the - * fact that cmpxchg8b returns the current 64-bit value - * of the memory location we are touching: - */ - asm volatile( - "mov %%ebx, %%eax\n\t" - "mov %%ecx, %%edx\n\t" - LOCK_PREFIX "cmpxchg8b %1\n" - : "=&A" (res) - : "m" (*ptr) - ); - - return res; -} - -extern u64 atomic64_read(atomic64_t *ptr); + long long r; + asm volatile(ATOMIC64_ALTERNATIVE(read) + : "=A" (r), "+c" (v) + : : "memory" + ); + return r; + } /** * atomic64_add_return - add and return - * @delta: integer value to add - * @ptr: pointer to type atomic64_t + * @i: integer value to add + * @v: pointer to type atomic64_t * - * Atomically adds @delta to @ptr and returns @delta + *@ptr + * Atomically adds @i to @v and returns @i + *@v */ -extern u64 atomic64_add_return(u64 delta, atomic64_t *ptr); +static inline long long atomic64_add_return(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE(add_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} /* * Other variants with different arithmetic operators: */ -extern u64 atomic64_sub_return(u64 delta, atomic64_t *ptr); -extern u64 atomic64_inc_return(atomic64_t *ptr); -extern u64 atomic64_dec_return(atomic64_t *ptr); +static inline long long atomic64_sub_return(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE(sub_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} + +static inline long long atomic64_inc_return(atomic64_t *v) +{ + long long a; + asm volatile(ATOMIC64_ALTERNATIVE(inc_return) + : "=A" (a) + : "S" (v) + : "memory", "ecx" + ); + return a; +} + +static inline long long atomic64_dec_return(atomic64_t *v) +{ + long long a; + asm volatile(ATOMIC64_ALTERNATIVE(dec_return) + : "=A" (a) + : "S" (v) + : "memory", "ecx" + ); + return a; +} /** * atomic64_add - add integer to atomic64 variable - * @delta: integer value to add - * @ptr: pointer to type atomic64_t + * @i: integer value to add + * @v: pointer to type atomic64_t * - * Atomically adds @delta to @ptr. + * Atomically adds @i to @v. */ -extern void atomic64_add(u64 delta, atomic64_t *ptr); +static inline long long atomic64_add(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(add, add_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} /** * atomic64_sub - subtract the atomic64 variable - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t + * @i: integer value to subtract + * @v: pointer to type atomic64_t * - * Atomically subtracts @delta from @ptr. + * Atomically subtracts @i from @v. */ -extern void atomic64_sub(u64 delta, atomic64_t *ptr); +static inline long long atomic64_sub(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(sub, sub_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} /** * atomic64_sub_and_test - subtract value from variable and test result - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t - * - * Atomically subtracts @delta from @ptr and returns + * @i: integer value to subtract + * @v: pointer to type atomic64_t + * + * Atomically subtracts @i from @v and returns * true if the result is zero, or false for all * other cases. */ -extern int atomic64_sub_and_test(u64 delta, atomic64_t *ptr); +static inline int atomic64_sub_and_test(long long i, atomic64_t *v) +{ + return atomic64_sub_return(i, v) == 0; +} /** * atomic64_inc - increment atomic64 variable - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically increments @ptr by 1. + * Atomically increments @v by 1. */ -extern void atomic64_inc(atomic64_t *ptr); +static inline void atomic64_inc(atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(inc, inc_return) + : : "S" (v) + : "memory", "eax", "ecx", "edx" + ); +} /** * atomic64_dec - decrement atomic64 variable @@ -124,37 +208,97 @@ extern void atomic64_inc(atomic64_t *ptr); * * Atomically decrements @ptr by 1. */ -extern void atomic64_dec(atomic64_t *ptr); +static inline void atomic64_dec(atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(dec, dec_return) + : : "S" (v) + : "memory", "eax", "ecx", "edx" + ); +} /** * atomic64_dec_and_test - decrement and test - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically decrements @ptr by 1 and + * Atomically decrements @v by 1 and * returns true if the result is 0, or false for all other * cases. */ -extern int atomic64_dec_and_test(atomic64_t *ptr); +static inline int atomic64_dec_and_test(atomic64_t *v) +{ + return atomic64_dec_return(v) == 0; +} /** * atomic64_inc_and_test - increment and test - * @ptr: pointer to type atomic64_t + * @v: pointer to type atomic64_t * - * Atomically increments @ptr by 1 + * Atomically increments @v by 1 * and returns true if the result is zero, or false for all * other cases. */ -extern int atomic64_inc_and_test(atomic64_t *ptr); +static inline int atomic64_inc_and_test(atomic64_t *v) +{ + return atomic64_inc_return(v) == 0; +} /** * atomic64_add_negative - add and test if negative - * @delta: integer value to add - * @ptr: pointer to type atomic64_t + * @i: integer value to add + * @v: pointer to type atomic64_t * - * Atomically adds @delta to @ptr and returns true + * Atomically adds @i to @v and returns true * if the result is negative, or false when * result is greater than or equal to zero. */ -extern int atomic64_add_negative(u64 delta, atomic64_t *ptr); +static inline int atomic64_add_negative(long long i, atomic64_t *v) +{ + return atomic64_add_return(i, v) < 0; +} + +/** + * atomic64_add_unless - add unless the number is a given value + * @v: pointer of type atomic64_t + * @a: the amount to add to v... + * @u: ...unless v is equal to u. + * + * Atomically adds @a to @v, so long as it was not @u. + * Returns non-zero if @v was not @u, and zero otherwise. + */ +static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u) +{ + unsigned low = (unsigned)u; + unsigned high = (unsigned)(u >> 32); + asm volatile(ATOMIC64_ALTERNATIVE(add_unless) "\n\t" + : "+A" (a), "+c" (v), "+S" (low), "+D" (high) + : : "memory"); + return (int)a; +} + + +static inline int atomic64_inc_not_zero(atomic64_t *v) +{ + int r; + asm volatile(ATOMIC64_ALTERNATIVE(inc_not_zero) + : "=a" (r) + : "S" (v) + : "ecx", "edx", "memory" + ); + return r; +} + +static inline long long atomic64_dec_if_positive(atomic64_t *v) +{ + long long r; + asm volatile(ATOMIC64_ALTERNATIVE(dec_if_positive) + : "=A" (r) + : "S" (v) + : "ecx", "memory" + ); + return r; +} + +#undef ATOMIC64_ALTERNATIVE +#undef ATOMIC64_ALTERNATIVE_ #endif /* _ASM_X86_ATOMIC64_32_H */ diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index cffd754..05d686b 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -26,11 +26,12 @@ obj-y += msr.o msr-reg.o msr-reg-export.o ifeq ($(CONFIG_X86_32),y) obj-y += atomic64_32.o + lib-y += atomic64_cx8_32.o lib-y += checksum_32.o lib-y += strstr_32.o lib-y += semaphore_32.o string_32.o ifneq ($(CONFIG_X86_CMPXCHG64),y) - lib-y += cmpxchg8b_emu.o + lib-y += cmpxchg8b_emu.o atomic64_386_32.o endif lib-$(CONFIG_X86_USE_3DNOW) += mmx_32.o else diff --git a/arch/x86/lib/atomic64_32.c b/arch/x86/lib/atomic64_32.c index 824fa0b..540179e 100644 --- a/arch/x86/lib/atomic64_32.c +++ b/arch/x86/lib/atomic64_32.c @@ -6,225 +6,54 @@ #include <asm/cmpxchg.h> #include <asm/atomic.h> -static noinline u64 cmpxchg8b(u64 *ptr, u64 old, u64 new) -{ - u32 low = new; - u32 high = new >> 32; - - asm volatile( - LOCK_PREFIX "cmpxchg8b %1\n" - : "+A" (old), "+m" (*ptr) - : "b" (low), "c" (high) - ); - return old; -} - -u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val) -{ - return cmpxchg8b(&ptr->counter, old_val, new_val); -} -EXPORT_SYMBOL(atomic64_cmpxchg); - -/** - * atomic64_xchg - xchg atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign - * - * Atomically xchgs the value of @ptr to @new_val and returns - * the old value. - */ -u64 atomic64_xchg(atomic64_t *ptr, u64 new_val) -{ - /* - * Try first with a (possibly incorrect) assumption about - * what we have there. We'll do two loops most likely, - * but we'll get an ownership MESI transaction straight away - * instead of a read transaction followed by a - * flush-for-ownership transaction: - */ - u64 old_val, real_val = 0; - - do { - old_val = real_val; - - real_val = atomic64_cmpxchg(ptr, old_val, new_val); - - } while (real_val != old_val); - - return old_val; -} -EXPORT_SYMBOL(atomic64_xchg); - -/** - * atomic64_set - set atomic64 variable - * @ptr: pointer to type atomic64_t - * @new_val: value to assign - * - * Atomically sets the value of @ptr to @new_val. - */ -void atomic64_set(atomic64_t *ptr, u64 new_val) -{ - atomic64_xchg(ptr, new_val); -} -EXPORT_SYMBOL(atomic64_set); - -/** -EXPORT_SYMBOL(atomic64_read); - * atomic64_add_return - add and return - * @delta: integer value to add - * @ptr: pointer to type atomic64_t - * - * Atomically adds @delta to @ptr and returns @delta + *@ptr - */ -noinline u64 atomic64_add_return(u64 delta, atomic64_t *ptr) -{ - /* - * Try first with a (possibly incorrect) assumption about - * what we have there. We'll do two loops most likely, - * but we'll get an ownership MESI transaction straight away - * instead of a read transaction followed by a - * flush-for-ownership transaction: - */ - u64 old_val, new_val, real_val = 0; - - do { - old_val = real_val; - new_val = old_val + delta; - - real_val = atomic64_cmpxchg(ptr, old_val, new_val); - - } while (real_val != old_val); - - return new_val; -} -EXPORT_SYMBOL(atomic64_add_return); - -u64 atomic64_sub_return(u64 delta, atomic64_t *ptr) -{ - return atomic64_add_return(-delta, ptr); -} -EXPORT_SYMBOL(atomic64_sub_return); - -u64 atomic64_inc_return(atomic64_t *ptr) -{ - return atomic64_add_return(1, ptr); -} -EXPORT_SYMBOL(atomic64_inc_return); - -u64 atomic64_dec_return(atomic64_t *ptr) -{ - return atomic64_sub_return(1, ptr); -} -EXPORT_SYMBOL(atomic64_dec_return); - -/** - * atomic64_add - add integer to atomic64 variable - * @delta: integer value to add - * @ptr: pointer to type atomic64_t - * - * Atomically adds @delta to @ptr. - */ -void atomic64_add(u64 delta, atomic64_t *ptr) -{ - atomic64_add_return(delta, ptr); -} -EXPORT_SYMBOL(atomic64_add); - -/** - * atomic64_sub - subtract the atomic64 variable - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t - * - * Atomically subtracts @delta from @ptr. - */ -void atomic64_sub(u64 delta, atomic64_t *ptr) -{ - atomic64_add(-delta, ptr); -} -EXPORT_SYMBOL(atomic64_sub); - -/** - * atomic64_sub_and_test - subtract value from variable and test result - * @delta: integer value to subtract - * @ptr: pointer to type atomic64_t - * - * Atomically subtracts @delta from @ptr and returns - * true if the result is zero, or false for all - * other cases. - */ -int atomic64_sub_and_test(u64 delta, atomic64_t *ptr) -{ - u64 new_val = atomic64_sub_return(delta, ptr); - - return new_val == 0; -} -EXPORT_SYMBOL(atomic64_sub_and_test); - -/** - * atomic64_inc - increment atomic64 variable - * @ptr: pointer to type atomic64_t - * - * Atomically increments @ptr by 1. - */ -void atomic64_inc(atomic64_t *ptr) -{ - atomic64_add(1, ptr); -} -EXPORT_SYMBOL(atomic64_inc); - -/** - * atomic64_dec - decrement atomic64 variable - * @ptr: pointer to type atomic64_t - * - * Atomically decrements @ptr by 1. - */ -void atomic64_dec(atomic64_t *ptr) -{ - atomic64_sub(1, ptr); -} -EXPORT_SYMBOL(atomic64_dec); - -/** - * atomic64_dec_and_test - decrement and test - * @ptr: pointer to type atomic64_t - * - * Atomically decrements @ptr by 1 and - * returns true if the result is 0, or false for all other - * cases. - */ -int atomic64_dec_and_test(atomic64_t *ptr) -{ - return atomic64_sub_and_test(1, ptr); -} -EXPORT_SYMBOL(atomic64_dec_and_test); - -/** - * atomic64_inc_and_test - increment and test - * @ptr: pointer to type atomic64_t - * - * Atomically increments @ptr by 1 - * and returns true if the result is zero, or false for all - * other cases. - */ -int atomic64_inc_and_test(atomic64_t *ptr) -{ - return atomic64_sub_and_test(-1, ptr); -} -EXPORT_SYMBOL(atomic64_inc_and_test); - -/** - * atomic64_add_negative - add and test if negative - * @delta: integer value to add - * @ptr: pointer to type atomic64_t - * - * Atomically adds @delta to @ptr and returns true - * if the result is negative, or false when - * result is greater than or equal to zero. - */ -int atomic64_add_negative(u64 delta, atomic64_t *ptr) -{ - s64 new_val = atomic64_add_return(delta, ptr); - - return new_val < 0; -} -EXPORT_SYMBOL(atomic64_add_negative); +long long atomic64_read_cx8(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_read_cx8); +long long atomic64_set_cx8(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_set_cx8); +long long atomic64_xchg_cx8(long long, unsigned high); +EXPORT_SYMBOL(atomic64_xchg_cx8); +long long atomic64_add_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_add_return_cx8); +long long atomic64_sub_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_sub_return_cx8); +long long atomic64_inc_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_return_cx8); +long long atomic64_dec_return_cx8(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_return_cx8); +long long atomic64_dec_if_positive_cx8(atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_if_positive_cx8); +int atomic64_inc_not_zero_cx8(atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_not_zero_cx8); +int atomic64_add_unless_cx8(atomic64_t *v, long long a, long long u); +EXPORT_SYMBOL(atomic64_add_unless_cx8); + +#ifndef CONFIG_X86_CMPXCHG64 +long long atomic64_read_386(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_read_386); +long long atomic64_set_386(long long, const atomic64_t *v); +EXPORT_SYMBOL(atomic64_set_386); +long long atomic64_xchg_386(long long, unsigned high); +EXPORT_SYMBOL(atomic64_xchg_386); +long long atomic64_add_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_add_return_386); +long long atomic64_sub_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_sub_return_386); +long long atomic64_inc_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_return_386); +long long atomic64_dec_return_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_return_386); +long long atomic64_add_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_add_386); +long long atomic64_sub_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_sub_386); +long long atomic64_inc_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_386); +long long atomic64_dec_386(long long a, atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_386); +long long atomic64_dec_if_positive_386(atomic64_t *v); +EXPORT_SYMBOL(atomic64_dec_if_positive_386); +int atomic64_inc_not_zero_386(atomic64_t *v); +EXPORT_SYMBOL(atomic64_inc_not_zero_386); +int atomic64_add_unless_386(atomic64_t *v, long long a, long long u); +EXPORT_SYMBOL(atomic64_add_unless_386); +#endif diff --git a/arch/x86/lib/atomic64_386_32.S b/arch/x86/lib/atomic64_386_32.S new file mode 100644 index 0000000..5db07fe --- /dev/null +++ b/arch/x86/lib/atomic64_386_32.S @@ -0,0 +1,175 @@ +/* + * atomic64_t for 386/486 + * + * Copyright © 2010 Luca Barbieri + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/linkage.h> +#include <asm/alternative-asm.h> +#include <asm/dwarf2.h> + +/* if you want SMP support, implement these with real spinlocks */ +.macro LOCK reg + pushfl + CFI_ADJUST_CFA_OFFSET 4 + cli +.endm + +.macro UNLOCK reg + popfl + CFI_ADJUST_CFA_OFFSET -4 +.endm + +.macro BEGIN func reg +$v = \reg + +ENTRY(atomic64_\func\()_386) + CFI_STARTPROC + LOCK $v + +.macro RETURN + UNLOCK $v + ret +.endm + +.macro END_ + CFI_ENDPROC +ENDPROC(atomic64_\func\()_386) +.purgem RETURN +.purgem END_ +.purgem END +.endm + +.macro END +RETURN +END_ +.endm +.endm + +BEGIN read %ecx + movl ($v), %eax + movl 4($v), %edx +END + +BEGIN set %esi + movl %ebx, ($v) + movl %ecx, 4($v) +END + +BEGIN xchg %esi + movl ($v), %eax + movl 4($v), %edx + movl %ebx, ($v) + movl %ecx, 4($v) +END + +BEGIN add %ecx + addl %eax, ($v) + adcl %edx, 4($v) +END + +BEGIN add_return %ecx + addl ($v), %eax + adcl 4($v), %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN sub %ecx + subl %eax, ($v) + sbbl %edx, 4($v) +END + +BEGIN sub_return %ecx + negl %edx + negl %eax + sbbl $0, %edx + addl ($v), %eax + adcl 4($v), %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN inc %esi + addl $1, ($v) + adcl $0, 4($v) +END + +BEGIN inc_return %esi + movl ($v), %eax + movl 4($v), %edx + addl $1, %eax + adcl $0, %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN dec %esi + subl $1, ($v) + sbbl $0, 4($v) +END + +BEGIN dec_return %esi + movl ($v), %eax + movl 4($v), %edx + subl $1, %eax + sbbl $0, %edx + movl %eax, ($v) + movl %edx, 4($v) +END + +BEGIN add_unless %ecx + addl %eax, %esi + adcl %edx, %edi + addl ($v), %eax + adcl 4($v), %edx + cmpl %eax, %esi + je 3f +1: + movl %eax, ($v) + movl %edx, 4($v) + xorl %eax, %eax +2: +RETURN +3: + cmpl %edx, %edi + jne 1b + movl $1, %eax + jmp 2b +END_ + +BEGIN inc_not_zero %esi + movl ($v), %eax + movl 4($v), %edx + testl %eax, %eax + je 3f +1: + addl $1, %eax + adcl $0, %edx + movl %eax, ($v) + movl %edx, 4($v) + xorl %eax, %eax +2: +RETURN +3: + testl %edx, %edx + jne 1b + movl $1, %eax + jmp 2b +END_ + +BEGIN dec_if_positive %esi + movl ($v), %eax + movl 4($v), %edx + subl $1, %eax + sbbl $0, %edx + js 1f + movl %eax, ($v) + movl %edx, 4($v) +1: +END diff --git a/arch/x86/lib/atomic64_cx8_32.S b/arch/x86/lib/atomic64_cx8_32.S new file mode 100644 index 0000000..e49c4eb --- /dev/null +++ b/arch/x86/lib/atomic64_cx8_32.S @@ -0,0 +1,225 @@ +/* + * atomic64_t for 586+ + * + * Copyright © 2010 Luca Barbieri + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/linkage.h> +#include <asm/alternative-asm.h> +#include <asm/dwarf2.h> + +.macro SAVE reg + pushl %\reg + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET \reg, 0 +.endm + +.macro RESTORE reg + popl %\reg + CFI_ADJUST_CFA_OFFSET -4 + CFI_RESTORE \reg +.endm + +.macro read64 reg + movl %ebx, %eax + movl %ecx, %edx +/* we need LOCK_PREFIX since otherwise cmpxchg8b always does the write */ + LOCK_PREFIX + cmpxchg8b (\reg) +.endm + +ENTRY(atomic64_read_cx8) + CFI_STARTPROC + + read64 %ecx + ret + CFI_ENDPROC +ENDPROC(atomic64_read_cx8) + +ENTRY(atomic64_set_cx8) + CFI_STARTPROC + +1: +/* we don't need LOCK_PREFIX since aligned 64-bit writes + * are atomic on 586 and newer */ + cmpxchg8b (%esi) + jne 1b + + ret + CFI_ENDPROC +ENDPROC(atomic64_set_cx8) + +ENTRY(atomic64_xchg_cx8) + CFI_STARTPROC + + movl %ebx, %eax + movl %ecx, %edx +1: + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + + ret + CFI_ENDPROC +ENDPROC(atomic64_xchg_cx8) + +.macro addsub_return func ins insc +ENTRY(atomic64_\func\()_return_cx8) + CFI_STARTPROC + SAVE ebp + SAVE ebx + SAVE esi + SAVE edi + + movl %eax, %esi + movl %edx, %edi + movl %ecx, %ebp + + read64 %ebp +1: + movl %eax, %ebx + movl %edx, %ecx + \ins\()l %esi, %ebx + \insc\()l %edi, %ecx + LOCK_PREFIX + cmpxchg8b (%ebp) + jne 1b + +10: + movl %ebx, %eax + movl %ecx, %edx + RESTORE edi + RESTORE esi + RESTORE ebx + RESTORE ebp + ret + CFI_ENDPROC +ENDPROC(atomic64_\func\()_return_cx8) +.endm + +addsub_return add add adc +addsub_return sub sub sbb + +.macro incdec_return func ins insc +ENTRY(atomic64_\func\()_return_cx8) + CFI_STARTPROC + SAVE ebx + + read64 %esi +1: + movl %eax, %ebx + movl %edx, %ecx + \ins\()l $1, %ebx + \insc\()l $0, %ecx + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + +10: + movl %ebx, %eax + movl %ecx, %edx + RESTORE ebx + ret + CFI_ENDPROC +ENDPROC(atomic64_\func\()_return_cx8) +.endm + +incdec_return inc add adc +incdec_return dec sub sbb + +ENTRY(atomic64_dec_if_positive_cx8) + CFI_STARTPROC + SAVE ebx + + read64 %esi +1: + movl %eax, %ebx + movl %edx, %ecx + subl $1, %ebx + sbb $0, %ecx + js 2f + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + +2: + movl %ebx, %eax + movl %ecx, %edx + RESTORE ebx + ret + CFI_ENDPROC +ENDPROC(atomic64_dec_if_positive_cx8) + +ENTRY(atomic64_add_unless_cx8) + CFI_STARTPROC + SAVE ebp + SAVE ebx +/* these just push these two parameters on the stack */ + SAVE edi + SAVE esi + + movl %ecx, %ebp + movl %eax, %esi + movl %edx, %edi + + read64 %ebp +1: + cmpl %eax, 0(%esp) + je 4f +2: + movl %eax, %ebx + movl %edx, %ecx + addl %esi, %ebx + adcl %edi, %ecx + LOCK_PREFIX + cmpxchg8b (%ebp) + jne 1b + + xorl %eax, %eax +3: + addl $8, %esp + CFI_ADJUST_CFA_OFFSET -8 + RESTORE ebx + RESTORE ebp + ret +4: + cmpl %edx, 4(%esp) + jne 2b + movl $1, %eax + jmp 3b + CFI_ENDPROC +ENDPROC(atomic64_add_unless_cx8) + +ENTRY(atomic64_inc_not_zero_cx8) + CFI_STARTPROC + SAVE ebx + + read64 %esi +1: + testl %eax, %eax + je 4f +2: + movl %eax, %ebx + movl %edx, %ecx + addl $1, %ebx + adcl $0, %ecx + LOCK_PREFIX + cmpxchg8b (%esi) + jne 1b + + xorl %eax, %eax +3: + RESTORE ebx + ret +4: + testl %edx, %edx + jne 2b + movl $1, %eax + jmp 3b + CFI_ENDPROC +ENDPROC(atomic64_inc_not_zero_cx8) ^ permalink raw reply related [flat|nested] 11+ messages in thread
end of thread, other threads:[~2010-04-30 17:06 UTC | newest] Thread overview: 11+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2010-02-24 9:54 [PATCH 0/4] x86-32: improve atomic64_t functions (v3, for tip/x86/asm) Luca Barbieri 2010-02-24 9:54 ` [PATCH 1/4] x86: add support for lock prefix in alternatives (v2) Luca Barbieri 2010-02-26 5:12 ` [tip:x86/atomic] x86: Add support for lock prefix in alternatives tip-bot for Luca Barbieri 2010-04-29 23:24 ` [tip:x86/atomic] x86: Fix LOCK_PREFIX_HERE for uniprocessor build tip-bot for H. Peter Anvin 2010-02-24 9:54 ` [PATCH 2/4] x86-32: allow UP/SMP lock replacement in cmpxchg64 (v2) Luca Barbieri 2010-02-26 5:12 ` [tip:x86/atomic] x86-32: Allow UP/SMP lock replacement in cmpxchg64 tip-bot for Luca Barbieri 2010-02-24 9:54 ` [PATCH 3/4] lib: add self-test for atomic64_t Luca Barbieri 2010-02-26 5:13 ` [tip:x86/atomic] lib: Add " tip-bot for Luca Barbieri 2010-03-01 19:59 ` [tip:x86/atomic] x86, atomic64: In selftest, distinguish x86-64 from 586+ tip-bot for H. Peter Anvin 2010-02-24 9:54 ` [PATCH 4/4] x86-32: rewrite 32-bit atomic64 functions in assembly (v3) Luca Barbieri 2010-02-26 5:13 ` [tip:x86/atomic] x86-32: Rewrite 32-bit atomic64 functions in assembly tip-bot for Luca Barbieri
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