diff options
Diffstat (limited to 'include/haproxy/atomic.h')
| -rw-r--r-- | include/haproxy/atomic.h | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/include/haproxy/atomic.h b/include/haproxy/atomic.h index d64e192..146f2ad 100644 --- a/include/haproxy/atomic.h +++ b/include/haproxy/atomic.h @@ -185,6 +185,7 @@ #define __ha_barrier_full() do { } while (0) #define __ha_compiler_barrier() do { } while (0) #define __ha_cpu_relax() ({ 1; }) +#define __ha_cpu_relax_for_read() ({ 1; }) #else /* !USE_THREAD */ @@ -198,10 +199,11 @@ #define HA_ATOMIC_LOAD(val) \ ({ \ - typeof(*(val)) ret = \ - ({ __sync_synchronize(); *(volatile typeof(val))val; }); \ + typeof((val)) __val_load = (val); \ + typeof(*(val)) __ret_val = \ + ({ __sync_synchronize(); *(volatile typeof(__val_load))__val_load; }); \ __sync_synchronize(); \ - ret; \ + __ret_val; \ }) #define HA_ATOMIC_STORE(val, new) \ @@ -586,6 +588,9 @@ __ha_cas_dw(void *target, void *compare, const void *set) /* short-lived CPU relaxation */ #define __ha_cpu_relax() ({ asm volatile("rep;nop\n"); 1; }) +/* dummy relaxation: x86 prefers not to wait at all in read loops */ +#define __ha_cpu_relax_for_read() ({ 1; }) + #elif defined(__arm__) && (defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__)) static __inline void @@ -651,6 +656,9 @@ static __inline int __ha_cas_dw(void *target, void *compare, const void *set) /* short-lived CPU relaxation */ #define __ha_cpu_relax() ({ asm volatile(""); 1; }) +/* short wait in read loops */ +#define __ha_cpu_relax_for_read() ({ asm volatile(""); 1; }) + #elif defined (__aarch64__) static __inline void @@ -697,6 +705,9 @@ __ha_barrier_atomic_full(void) */ #define __ha_cpu_relax() ({ asm volatile("isb" ::: "memory"); 1; }) +/* aarch64 prefers to wait for real in read loops */ +#define __ha_cpu_relax_for_read() ({ asm volatile("isb" ::: "memory"); 1; }) + #if defined(__ARM_FEATURE_ATOMICS) && !defined(__clang__) // ARMv8.1-A atomics /* returns 0 on failure, non-zero on success */ @@ -799,6 +810,9 @@ static __inline int __ha_cas_dw(void *target, void *compare, void *set) /* short-lived CPU relaxation */ #define __ha_cpu_relax() ({ asm volatile(""); 1; }) +/* default wait in read loops */ +#define __ha_cpu_relax_for_read() ({ asm volatile(""); 1; }) + #endif /* end of arch-specific barrier/dwcas */ static inline void __ha_compiler_barrier(void) |