| Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame] | 1 | #ifndef _TOOLS_LINUX_ASM_X86_BARRIER_H |
| 2 | #define _TOOLS_LINUX_ASM_X86_BARRIER_H |
| 3 | |
| 4 | /* |
| 5 | * Copied from the Linux kernel sources, and also moving code |
| 6 | * out from tools/perf/perf-sys.h so as to make it be located |
| 7 | * in a place similar as in the kernel sources. |
| 8 | * |
| 9 | * Force strict CPU ordering. |
| 10 | * And yes, this is required on UP too when we're talking |
| 11 | * to devices. |
| 12 | */ |
| 13 | |
| 14 | #if defined(__i386__) |
| 15 | /* |
| 16 | * Some non-Intel clones support out of order store. wmb() ceases to be a |
| 17 | * nop for these. |
| 18 | */ |
| 19 | #define mb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory") |
| 20 | #define rmb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory") |
| 21 | #define wmb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory") |
| 22 | #elif defined(__x86_64__) |
| 23 | #define mb() asm volatile("mfence":::"memory") |
| 24 | #define rmb() asm volatile("lfence":::"memory") |
| 25 | #define wmb() asm volatile("sfence" ::: "memory") |
| 26 | #endif |
| 27 | |
| 28 | #endif /* _TOOLS_LINUX_ASM_X86_BARRIER_H */ |