spinlock: spin non atomically while waiting for lock to be released

This commit is contained in:
Matheus
2025-09-01 22:24:15 -03:00
parent a04a437fef
commit ca60b47209
+7 -5
View File
@@ -10,8 +10,14 @@ typedef int spinlock_t;
#define SPINLOCK_INIT(x) x = SPINLOCK_INIT_VALUE #define SPINLOCK_INIT(x) x = SPINLOCK_INIT_VALUE
#define SPINLOCK_DEFINE(x) spinlock_t x = SPINLOCK_INIT_VALUE #define SPINLOCK_DEFINE(x) spinlock_t x = SPINLOCK_INIT_VALUE
static inline bool spinlock_try(spinlock_t *lock) {
return __sync_bool_compare_and_swap(lock, 0, 1);
}
static inline void spinlock_acquire(spinlock_t *lock) { static inline void spinlock_acquire(spinlock_t *lock) {
while(!__sync_bool_compare_and_swap(lock, 0, 1)) asm("pause"); while (!__sync_bool_compare_and_swap(lock, 0, 1)) {
while (*lock) asm volatile ("pause" : : : "memory");
}
} }
static inline bool spinlock_acquire_irq_clear(spinlock_t *lock) { static inline bool spinlock_acquire_irq_clear(spinlock_t *lock) {
@@ -20,10 +26,6 @@ static inline bool spinlock_acquire_irq_clear(spinlock_t *lock){
return ret; return ret;
} }
static inline bool spinlock_try(spinlock_t *lock){
return __sync_bool_compare_and_swap(lock, 0, 1);
}
static inline void spinlock_release(spinlock_t *lock) { static inline void spinlock_release(spinlock_t *lock) {
*lock = 0; *lock = 0;
} }