diff options
| -rw-r--r-- | ChangeLog | 8 | ||||
| -rw-r--r-- | thread.c | 60 |
2 files changed, 51 insertions, 17 deletions
@@ -1,3 +1,11 @@ +Fri Apr 29 10:07:13 2011 KOSAKI Motohiro <kosaki.motohiro@gmail.com> + + * thread.c (rb_mutex_lock, lock_func): Avoid busy loop and + performance degression. bm_vm3_thread_mutex.rb performance + change from 109.064sec to 16.331sec. + + * thread.c (init_lock_timeout): New helper function. + Thu Apr 28 16:15:49 2011 NAKAMURA Usaku <usa@ruby-lang.org> * win32/{win32.c,dir.h} (rb_w32_uopendir): new API to pass UTF-8 path. @@ -3208,24 +3208,49 @@ rb_mutex_trylock(VALUE self) return locked; } +static struct timespec init_lock_timeout(int timeout_ms) +{ + struct timespec ts; + struct timeval tv; + int ret; + + ret = gettimeofday(&tv, NULL); + if (ret < 0) + rb_sys_fail(0); + + ts.tv_sec = tv.tv_sec; + ts.tv_nsec = tv.tv_usec * 1000 + timeout_ms * 1000 * 1000; + if (ts.tv_nsec >= 1000000000) { + ts.tv_sec++; + ts.tv_nsec -= 1000000000; + } + + return ts; +} + static int -lock_func(rb_thread_t *th, mutex_t *mutex, int last_thread) +lock_func(rb_thread_t *th, mutex_t *mutex, int timeout_ms) { int interrupted = 0; -#if 0 /* for debug */ - native_thread_yield(); -#endif native_mutex_lock(&mutex->lock); th->transition_for_lock = 0; while (mutex->th || (mutex->th = th, 0)) { - if (last_thread) { - interrupted = 2; - break; - } + struct timespec ts; + int ret; mutex->cond_waiting++; - native_cond_wait(&mutex->cond, &mutex->lock); + if (timeout_ms) { + ts = init_lock_timeout(timeout_ms); + ret = native_cond_timedwait(&mutex->cond, &mutex->lock, &ts); + if (ret == ETIMEDOUT) { + interrupted = 2; + break; + } + } + else { + native_cond_wait(&mutex->cond, &mutex->lock); + } mutex->cond_notified--; if (RUBY_VM_INTERRUPTED(th)) { @@ -3236,11 +3261,6 @@ lock_func(rb_thread_t *th, mutex_t *mutex, int last_thread) th->transition_for_lock = 1; native_mutex_unlock(&mutex->lock); - if (interrupted == 2) native_thread_yield(); -#if 0 /* for debug */ - native_thread_yield(); -#endif - return interrupted; } @@ -3280,20 +3300,26 @@ rb_mutex_lock(VALUE self) while (mutex->th != th) { int interrupted; enum rb_thread_status prev_status = th->status; - int last_thread = 0; + int timeout_ms = 0; struct rb_unblock_callback oldubf; set_unblock_function(th, lock_interrupt, mutex, &oldubf); th->status = THREAD_STOPPED_FOREVER; th->vm->sleeper++; th->locking_mutex = self; + + /* + * Carefully! while some contended threads are in lock_fun(), + * vm->sleepr is unstable value. we have to avoid both deadlock + * and busy loop. + */ if (vm_living_thread_num(th->vm) == th->vm->sleeper) { - last_thread = 1; + timeout_ms = 100; } th->transition_for_lock = 1; BLOCKING_REGION_CORE({ - interrupted = lock_func(th, mutex, last_thread); + interrupted = lock_func(th, mutex, timeout_ms); }); th->transition_for_lock = 0; remove_signal_thread_list(th); |