diff options
| author | Ingo Molnar <mingo@kernel.org> | 2015-03-04 08:33:49 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-03-04 08:36:15 +0300 |
| commit | f8e92fb4b0ffc4d62279ab39f34e798e37e90b0b (patch) | |
| tree | 9caa8df664792e64ddcb4ea03fd418a8a529c82e /arch/x86/include/asm/processor.h | |
| parent | d2c032e3dc58137a7261a7824d3acce435db1d66 (diff) | |
| parent | dfecb95cdfeaf7872d83a96bec3a606e9cd95c8d (diff) | |
| download | linux-f8e92fb4b0ffc4d62279ab39f34e798e37e90b0b.tar.xz | |
Merge tag 'alternatives_padding' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp into x86/asm
Pull alternative instructions framework improvements from Borislav Petkov:
"A more involved rework of the alternatives framework to be able to
pad instructions and thus make using the alternatives macros more
straightforward and without having to figure out old and new instruction
sizes but have the toolchain figure that out for us.
Furthermore, it optimizes JMPs used so that fetch and decode can be
relieved with smaller versions of the JMPs, where possible.
Some stats:
x86_64 defconfig:
Alternatives sites total: 2478
Total padding added (in Bytes): 6051
The padding is currently done for:
X86_FEATURE_ALWAYS
X86_FEATURE_ERMS
X86_FEATURE_LFENCE_RDTSC
X86_FEATURE_MFENCE_RDTSC
X86_FEATURE_SMAP
This is with the latest version of the patchset. Of course, on each
machine the alternatives sites actually being patched are a proper
subset of the total number."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include/asm/processor.h')
| -rw-r--r-- | arch/x86/include/asm/processor.h | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index ec1c93588cef..7be2c9a6caba 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -761,10 +761,10 @@ extern char ignore_fpu_irq; #define ARCH_HAS_SPINLOCK_PREFETCH #ifdef CONFIG_X86_32 -# define BASE_PREFETCH ASM_NOP4 +# define BASE_PREFETCH "" # define ARCH_HAS_PREFETCH #else -# define BASE_PREFETCH "prefetcht0 (%1)" +# define BASE_PREFETCH "prefetcht0 %P1" #endif /* @@ -775,10 +775,9 @@ extern char ignore_fpu_irq; */ static inline void prefetch(const void *x) { - alternative_input(BASE_PREFETCH, - "prefetchnta (%1)", + alternative_input(BASE_PREFETCH, "prefetchnta %P1", X86_FEATURE_XMM, - "r" (x)); + "m" (*(const char *)x)); } /* @@ -788,10 +787,9 @@ static inline void prefetch(const void *x) */ static inline void prefetchw(const void *x) { - alternative_input(BASE_PREFETCH, - "prefetchw (%1)", - X86_FEATURE_3DNOW, - "r" (x)); + alternative_input(BASE_PREFETCH, "prefetchw %P1", + X86_FEATURE_3DNOWPREFETCH, + "m" (*(const char *)x)); } static inline void spin_lock_prefetch(const void *x) |