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| | #include "pthread_impl.h"
static inline void __lock_fast(volatile int *l)
{
extern void __lock_slow(volatile int*, int);
if (!libc.threads_minus_1) return;
/* fast path: INT_MIN for holding the lock, +1 to count this
thread in the critical section. */
int current = a_cas(l, 0, INT_MIN + 1);
if (!current) return;
__lock_slow(l, current);
}
static inline void __unlock_fast(volatile int *l)
{
/* We have to check if l[0] had been touched at all. */
if (l[0] < 0) {
if (a_fetch_add(l, -(INT_MIN + 1)) != (INT_MIN + 1)) {
__wake(l, 1, 1);
}
}
}
|