diff options
Diffstat (limited to 'lib/libthr/thread/thr_mutex.c')
| -rw-r--r-- | lib/libthr/thread/thr_mutex.c | 82 |
1 files changed, 37 insertions, 45 deletions
diff --git a/lib/libthr/thread/thr_mutex.c b/lib/libthr/thread/thr_mutex.c index b1e6d0c..2cc3ce0 100644 --- a/lib/libthr/thread/thr_mutex.c +++ b/lib/libthr/thread/thr_mutex.c @@ -67,12 +67,6 @@ #endif /* - * For adaptive mutexes, how many times to spin doing trylock2 - * before entering the kernel to block - */ -#define MUTEX_ADAPTIVE_SPINS 200 - -/* * Prototypes */ int __pthread_mutex_init(pthread_mutex_t *mutex, @@ -279,6 +273,16 @@ _pthread_mutex_destroy(pthread_mutex_t *mutex) return (ret); } + +#define ENQUEUE_MUTEX(curthread, m) \ + m->m_owner = curthread; \ + /* Add to the list of owned mutexes: */ \ + MUTEX_ASSERT_NOT_OWNED(m); \ + if ((m->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0) \ + TAILQ_INSERT_TAIL(&curthread->mutexq, m, m_qe); \ + else \ + TAILQ_INSERT_TAIL(&curthread->pp_mutexq, m, m_qe) + static int mutex_trylock_common(struct pthread *curthread, pthread_mutex_t *mutex) { @@ -290,13 +294,7 @@ mutex_trylock_common(struct pthread *curthread, pthread_mutex_t *mutex) m = *mutex; ret = _thr_umutex_trylock(&m->m_lock, id); if (ret == 0) { - m->m_owner = curthread; - /* Add to the list of owned mutexes. */ - MUTEX_ASSERT_NOT_OWNED(m); - if ((m->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0) - TAILQ_INSERT_TAIL(&curthread->mutexq, m, m_qe); - else - TAILQ_INSERT_TAIL(&curthread->pp_mutexq, m, m_qe); + ENQUEUE_MUTEX(curthread, m); } else if (m->m_owner == curthread) { ret = mutex_self_trylock(m); } /* else {} */ @@ -348,39 +346,43 @@ mutex_lock_common(struct pthread *curthread, pthread_mutex_t *mutex, struct pthread_mutex *m; uint32_t id; int ret; + int count; id = TID(curthread); m = *mutex; ret = _thr_umutex_trylock2(&m->m_lock, id); if (ret == 0) { - m->m_owner = curthread; - /* Add to the list of owned mutexes: */ - MUTEX_ASSERT_NOT_OWNED(m); - if ((m->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0) - TAILQ_INSERT_TAIL(&curthread->mutexq, m, m_qe); - else - TAILQ_INSERT_TAIL(&curthread->pp_mutexq, m, m_qe); + ENQUEUE_MUTEX(curthread, m); } else if (m->m_owner == curthread) { ret = mutex_self_lock(m, abstime); } else { - /* - * For adaptive mutexes, spin for a bit in the expectation - * that if the application requests this mutex type then - * the lock is likely to be released quickly and it is - * faster than entering the kernel - */ - if (m->m_type == PTHREAD_MUTEX_ADAPTIVE_NP) { - int count = MUTEX_ADAPTIVE_SPINS; + if (_thr_spinloops != 0 && _thr_is_smp && + !(m->m_lock.m_flags & UMUTEX_PRIO_PROTECT)) { + count = _thr_spinloops; + while (count && m->m_lock.m_owner != UMUTEX_UNOWNED) { + count--; + CPU_SPINWAIT; + } + if (count) { + ret = _thr_umutex_trylock2(&m->m_lock, id); + if (ret == 0) { + ENQUEUE_MUTEX(curthread, m); + return (ret); + } + } + } + if (_thr_yieldloops != 0) { + count = _thr_yieldloops; while (count--) { + _sched_yield(); ret = _thr_umutex_trylock2(&m->m_lock, id); - if (ret == 0) - break; - cpu_spinwait(); + if (ret == 0) { + ENQUEUE_MUTEX(curthread, m); + return (ret); + } } } - if (ret == 0) - goto done; if (abstime == NULL) { ret = __thr_umutex_lock(&m->m_lock); @@ -399,17 +401,8 @@ mutex_lock_common(struct pthread *curthread, pthread_mutex_t *mutex, if (ret == EINTR) ret = ETIMEDOUT; } -done: - if (ret == 0) { - m->m_owner = curthread; - /* Add to the list of owned mutexes: */ - MUTEX_ASSERT_NOT_OWNED(m); - if ((m->m_lock.m_flags & UMUTEX_PRIO_PROTECT) == 0) - TAILQ_INSERT_TAIL(&curthread->mutexq, m, m_qe); - else - TAILQ_INSERT_TAIL(&curthread->pp_mutexq, m, - m_qe); - } + if (ret == 0) + ENQUEUE_MUTEX(curthread, m); } return (ret); } @@ -529,7 +522,6 @@ mutex_self_trylock(pthread_mutex_t m) switch (m->m_type) { case PTHREAD_MUTEX_ERRORCHECK: case PTHREAD_MUTEX_NORMAL: - case PTHREAD_MUTEX_ADAPTIVE_NP: ret = EBUSY; break; |
