diff options
Diffstat (limited to 'include/linux/compiler.h')
| -rw-r--r-- | include/linux/compiler.h | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h new file mode 100644 index 0000000..26336dc --- /dev/null +++ b/include/linux/compiler.h @@ -0,0 +1,70 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ + +#ifndef __LINUX_COMPILER_H +#define __LINUX_COMPILER_H + +#define likely(x) __builtin_expect(!!(x), 1) +#define unlikely(x) __builtin_expect(!!(x), 0) + +#define READ_ONCE(x) (*(volatile typeof(x) *)&x) +#define WRITE_ONCE(x, v) (*(volatile typeof(x) *)&x) = (v) + +#define barrier() asm volatile("" ::: "memory") + +#if defined(__x86_64__) + +# define smp_rmb() barrier() +# define smp_wmb() barrier() +# define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc") + +# define smp_store_release(p, v) \ +do { \ + barrier(); \ + WRITE_ONCE(*p, v); \ +} while (0) + +# define smp_load_acquire(p) \ +({ \ + typeof(*p) ___p = READ_ONCE(*p); \ + barrier(); \ + ___p; \ +}) + +#elif defined(__aarch64__) + +# define smp_rmb() asm volatile("dmb ishld" ::: "memory") +# define smp_wmb() asm volatile("dmb ishst" ::: "memory") +# define smp_mb() asm volatile("dmb ish" ::: "memory") + +#endif + +#ifndef smp_mb +# define smp_mb() __sync_synchronize() +#endif + +#ifndef smp_rmb +# define smp_rmb() smp_mb() +#endif + +#ifndef smp_wmb +# define smp_wmb() smp_mb() +#endif + +#ifndef smp_store_release +# define smp_store_release(p, v) \ +do { \ + smp_mb(); \ + WRITE_ONCE(*p, v); \ +} while (0) +#endif + +#ifndef smp_load_acquire +# define smp_load_acquire(p) \ +({ \ + typeof(*p) ___p = READ_ONCE(*p); \ + smp_mb(); \ + ___p; \ +}) +#endif + +#endif /* __LINUX_COMPILER_H */ |