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| author | Ricardo Neri <ricardo.neri-calderon@linux.intel.com> | 2020-08-07 06:28:33 +0300 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-08-17 18:23:04 +0300 |
| commit | bf9c912f9a649776c2d741310486a6984edaac72 (patch) | |
| tree | bd117b159ac58aa892922bbcbb98a992ef3bb4c6 /arch/x86/include/asm/special_insns.h | |
| parent | 9123e3a74ec7b934a4a099e98af6a61c2f80bbf5 (diff) | |
| download | linux-bf9c912f9a649776c2d741310486a6984edaac72.tar.xz | |
x86/cpu: Use SERIALIZE in sync_core() when available
The SERIALIZE instruction gives software a way to force the processor to
complete all modifications to flags, registers and memory from previous
instructions and drain all buffered writes to memory before the next
instruction is fetched and executed. Thus, it serves the purpose of
sync_core(). Use it when available.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200807032833.17484-1-ricardo.neri-calderon@linux.intel.com
Diffstat (limited to 'arch/x86/include/asm/special_insns.h')
| -rw-r--r-- | arch/x86/include/asm/special_insns.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h index 59a3e13204c3..5999b0b3dd4a 100644 --- a/arch/x86/include/asm/special_insns.h +++ b/arch/x86/include/asm/special_insns.h @@ -234,6 +234,12 @@ static inline void clwb(volatile void *__p) #define nop() asm volatile ("nop") +static inline void serialize(void) +{ + /* Instruction opcode for SERIALIZE; supported in binutils >= 2.35. */ + asm volatile(".byte 0xf, 0x1, 0xe8" ::: "memory"); +} + #endif /* __KERNEL__ */ #endif /* _ASM_X86_SPECIAL_INSNS_H */ |