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Use *NSYNC for POSIX threads locking APIs

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Condition variables, barriers, and r/w locks now work very well.
This commit is contained in:
Justine Tunney 2022-09-11 11:02:07 -07:00
parent 3de35e196c
commit b5cb71ab84
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GPG key ID: BE714B4575D6E328
197 changed files with 3734 additions and 3817 deletions
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27
libc/thread/pthread_barrier_wait.c
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@ -17,9 +17,12 @@
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/intrin/atomic.h"
#include "libc/intrin/futex.internal.h"
#include "libc/thread/thread.h"
#include "libc/intrin/kprintf.h"
#include "libc/limits.h"
#include "libc/thread/thread.h"
#include "third_party/nsync/counter.h"
#include "third_party/nsync/futex.internal.h"
#include "third_party/nsync/time.h"
/**
* Waits for all threads to arrive at barrier.
@ -33,22 +36,10 @@
* thread which was the last arrival, or an errno on error
*/
int pthread_barrier_wait(pthread_barrier_t *barrier) {
if (atomic_fetch_add(&barrier->waits, 1) + 1 == barrier->count) {
if (atomic_fetch_add(&barrier->waits, 1) + 1 < barrier->count * 2) {
atomic_store_explicit(&barrier->popped, 1, memory_order_relaxed);
do {
_futex_wake(&barrier->popped, INT_MAX, barrier->pshared);
} while (atomic_load_explicit(&barrier->waits, memory_order_relaxed) <
barrier->count * 2);
atomic_store_explicit(&barrier->popped, 0, memory_order_relaxed);
}
atomic_store_explicit(&barrier->waits, 0, memory_order_relaxed);
if (nsync_counter_add(barrier->_nsync, -1)) {
nsync_counter_wait(barrier->_nsync, nsync_time_no_deadline);
return 0;
} else {
return PTHREAD_BARRIER_SERIAL_THREAD;
}
do {
_futex_wait(&barrier->popped, 0, barrier->pshared, 0);
} while (atomic_load_explicit(&barrier->waits, memory_order_relaxed) <
barrier->count);
atomic_fetch_add(&barrier->waits, 1);
return 0;
}