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Make improvements to locking

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This change makes pthread_mutex_lock() as fast as _spinlock() by
default. Thread instability issues on NetBSD have been resolved.
Improvements made to gdtoa thread code. Crash reporting will now
synchronize between threads in a slightly better way.
This commit is contained in:
Justine Tunney 2022-06-19 01:13:03 -07:00
parent 25041b8026
commit d5312b60f7
60 changed files with 890 additions and 629 deletions
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36
libc/intrin/pthread_mutex_unlock.c
View file

@ -18,28 +18,34 @@
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/bits/atomic.h"
#include "libc/calls/calls.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/intrin/kprintf.h"
#include "libc/intrin/pthread.h"
#include "libc/linux/futex.h"
#include "libc/nexgen32e/threaded.h"
/**
* Releases mutex.
* @return 0 on success or error number on failure
* @raises EPERM if in error check mode and not owned by caller
*/
int pthread_mutex_unlock(pthread_mutex_t *mutex) {
int owner;
if (mutex->attr == PTHREAD_MUTEX_ERRORCHECK && mutex->lock != gettid()) {
return EPERM;
int(pthread_mutex_unlock)(pthread_mutex_t *mutex) {
int me, owner;
switch (mutex->attr) {
case PTHREAD_MUTEX_ERRORCHECK:
me = gettid();
owner = atomic_load_explicit(&mutex->lock, memory_order_relaxed);
if (owner != me) return EPERM;
// fallthrough
case PTHREAD_MUTEX_RECURSIVE:
if (--mutex->reent) return 0;
// fallthrough
case PTHREAD_MUTEX_NORMAL:
atomic_store_explicit(&mutex->lock, 0, memory_order_relaxed);
if (IsLinux() &&
atomic_load_explicit(&mutex->waits, memory_order_relaxed)) {
_pthread_mutex_wake(mutex);
}
return 0;
default:
return EINVAL;
}
if (!--mutex->reent) {
atomic_store_explicit(&mutex->lock, 0, memory_order_relaxed);
if (IsLinux() &&
atomic_load_explicit(&mutex->waits, memory_order_acquire)) {
LinuxFutexWake(&mutex->lock, 1);
}
}
return 0;
}