18c2ecf20Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */
28c2ecf20Sopenharmony_ci#ifndef _TOOLS_LINUX_ASM_X86_BARRIER_H
38c2ecf20Sopenharmony_ci#define _TOOLS_LINUX_ASM_X86_BARRIER_H
48c2ecf20Sopenharmony_ci
58c2ecf20Sopenharmony_ci/*
68c2ecf20Sopenharmony_ci * Copied from the Linux kernel sources, and also moving code
78c2ecf20Sopenharmony_ci * out from tools/perf/perf-sys.h so as to make it be located
88c2ecf20Sopenharmony_ci * in a place similar as in the kernel sources.
98c2ecf20Sopenharmony_ci *
108c2ecf20Sopenharmony_ci * Force strict CPU ordering.
118c2ecf20Sopenharmony_ci * And yes, this is required on UP too when we're talking
128c2ecf20Sopenharmony_ci * to devices.
138c2ecf20Sopenharmony_ci */
148c2ecf20Sopenharmony_ci
158c2ecf20Sopenharmony_ci#if defined(__i386__)
168c2ecf20Sopenharmony_ci/*
178c2ecf20Sopenharmony_ci * Some non-Intel clones support out of order store. wmb() ceases to be a
188c2ecf20Sopenharmony_ci * nop for these.
198c2ecf20Sopenharmony_ci */
208c2ecf20Sopenharmony_ci#define mb()	asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
218c2ecf20Sopenharmony_ci#define rmb()	asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
228c2ecf20Sopenharmony_ci#define wmb()	asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
238c2ecf20Sopenharmony_ci#elif defined(__x86_64__)
248c2ecf20Sopenharmony_ci#define mb()	asm volatile("mfence" ::: "memory")
258c2ecf20Sopenharmony_ci#define rmb()	asm volatile("lfence" ::: "memory")
268c2ecf20Sopenharmony_ci#define wmb()	asm volatile("sfence" ::: "memory")
278c2ecf20Sopenharmony_ci#define smp_rmb() barrier()
288c2ecf20Sopenharmony_ci#define smp_wmb() barrier()
298c2ecf20Sopenharmony_ci#define smp_mb()  asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc")
308c2ecf20Sopenharmony_ci#endif
318c2ecf20Sopenharmony_ci
328c2ecf20Sopenharmony_ci#if defined(__x86_64__)
338c2ecf20Sopenharmony_ci#define smp_store_release(p, v)			\
348c2ecf20Sopenharmony_cido {						\
358c2ecf20Sopenharmony_ci	barrier();				\
368c2ecf20Sopenharmony_ci	WRITE_ONCE(*p, v);			\
378c2ecf20Sopenharmony_ci} while (0)
388c2ecf20Sopenharmony_ci
398c2ecf20Sopenharmony_ci#define smp_load_acquire(p)			\
408c2ecf20Sopenharmony_ci({						\
418c2ecf20Sopenharmony_ci	typeof(*p) ___p1 = READ_ONCE(*p);	\
428c2ecf20Sopenharmony_ci	barrier();				\
438c2ecf20Sopenharmony_ci	___p1;					\
448c2ecf20Sopenharmony_ci})
458c2ecf20Sopenharmony_ci#endif /* defined(__x86_64__) */
468c2ecf20Sopenharmony_ci#endif /* _TOOLS_LINUX_ASM_X86_BARRIER_H */
47