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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _TOOLS_LINUX_ASM_X86_BARRIER_H
- #define _TOOLS_LINUX_ASM_X86_BARRIER_H
- /*
- * Copied from the Linux kernel sources, and also moving code
- * out from tools/perf/perf-sys.h so as to make it be located
- * in a place similar as in the kernel sources.
- *
- * Force strict CPU ordering.
- * And yes, this is required on UP too when we're talking
- * to devices.
- */
- #if defined(__i386__)
- /*
- * Some non-Intel clones support out of order store. wmb() ceases to be a
- * nop for these.
- */
- #define mb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
- #define rmb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
- #define wmb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
- #elif defined(__x86_64__)
- #define mb() asm volatile("mfence" ::: "memory")
- #define rmb() asm volatile("lfence" ::: "memory")
- #define wmb() asm volatile("sfence" ::: "memory")
- #define smp_rmb() barrier()
- #define smp_wmb() barrier()
- #define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc")
- #endif
- #if defined(__x86_64__)
- #define smp_store_release(p, v) \
- do { \
- barrier(); \
- WRITE_ONCE(*p, v); \
- } while (0)
- #define smp_load_acquire(p) \
- ({ \
- typeof(*p) ___p1 = READ_ONCE(*p); \
- barrier(); \
- ___p1; \
- })
- #endif /* defined(__x86_64__) */
- #endif /* _TOOLS_LINUX_ASM_X86_BARRIER_H */
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