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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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25
libc/intrin/pthread_mutex_trylock.c
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@ -20,7 +20,11 @@
#include "libc/calls/calls.h"
#include "libc/errno.h"
#include "libc/intrin/atomic.h"
#include "libc/intrin/likely.h"
#include "libc/intrin/weaken.h"
#include "libc/thread/thread.h"
#include "libc/thread/tls.h"
#include "third_party/nsync/mu.h"
/**
* Locks mutex if it isn't locked already.
@ -35,10 +39,21 @@
int pthread_mutex_trylock(pthread_mutex_t *mutex) {
int c, d, t;
if (mutex->type == PTHREAD_MUTEX_NORMAL) {
if (LIKELY(__tls_enabled && //
mutex->_type == PTHREAD_MUTEX_NORMAL && //
mutex->_pshared == PTHREAD_PROCESS_PRIVATE && //
weaken(nsync_mu_trylock))) {
if (weaken(nsync_mu_trylock)((nsync_mu *)mutex)) {
return 0;
} else {
return EBUSY;
}
}
if (mutex->_type == PTHREAD_MUTEX_NORMAL) {
c = 0;
if (atomic_compare_exchange_strong_explicit(
&mutex->lock, &c, 1, memory_order_acquire, memory_order_relaxed)) {
&mutex->_lock, &c, 1, memory_order_acquire, memory_order_relaxed)) {
return 0;
} else {
return EBUSY;
@ -49,14 +64,14 @@ int pthread_mutex_trylock(pthread_mutex_t *mutex) {
t = gettid();
d = 0x10100000 | t;
if (!atomic_compare_exchange_strong_explicit(
&mutex->lock, &c, d, memory_order_acquire, memory_order_relaxed)) {
if ((c & 0x000fffff) != t || mutex->type == PTHREAD_MUTEX_ERRORCHECK) {
&mutex->_lock, &c, d, memory_order_acquire, memory_order_relaxed)) {
if ((c & 0x000fffff) != t || mutex->_type == PTHREAD_MUTEX_ERRORCHECK) {
return EBUSY;
}
if ((c & 0x0ff00000) == 0x0ff00000) {
return EAGAIN;
}
atomic_fetch_add_explicit(&mutex->lock, 0x00100000, memory_order_relaxed);
atomic_fetch_add_explicit(&mutex->_lock, 0x00100000, memory_order_relaxed);
}
return 0;