Remove duplication in pthread_mutex.cpp.
Also add unit tests about thread woken up by pthread_mutex_unlock. Bug: 19216648 Change-Id: I8bde8105b00186c52a2f41d92458ae4a5eb90426
This commit is contained in:
parent
c3307dc43b
commit
5b8e7cd957
@ -237,7 +237,7 @@ int pthread_mutexattr_getpshared(const pthread_mutexattr_t* attr, int* pshared)
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return 0;
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}
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static inline atomic_int* MUTEX_TO_ATOMIC_POINTER(pthread_mutex_t* mutex) {
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static inline atomic_int* get_mutex_value_pointer(pthread_mutex_t* mutex) {
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static_assert(sizeof(atomic_int) == sizeof(mutex->value),
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"mutex->value should actually be atomic_int in implementation.");
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@ -247,7 +247,7 @@ static inline atomic_int* MUTEX_TO_ATOMIC_POINTER(pthread_mutex_t* mutex) {
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}
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int pthread_mutex_init(pthread_mutex_t* mutex, const pthread_mutexattr_t* attr) {
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atomic_int* mutex_value_ptr = MUTEX_TO_ATOMIC_POINTER(mutex);
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atomic_int* mutex_value_ptr = get_mutex_value_pointer(mutex);
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if (__predict_true(attr == NULL)) {
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atomic_init(mutex_value_ptr, MUTEX_TYPE_BITS_NORMAL);
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@ -277,6 +277,19 @@ int pthread_mutex_init(pthread_mutex_t* mutex, const pthread_mutexattr_t* attr)
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return 0;
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}
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static inline int __pthread_normal_mutex_trylock(atomic_int* mutex_value_ptr, int shared) {
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const int unlocked = shared | MUTEX_STATE_BITS_UNLOCKED;
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const int locked_uncontended = shared | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
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int mvalue = unlocked;
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if (__predict_true(atomic_compare_exchange_strong_explicit(mutex_value_ptr, &mvalue,
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locked_uncontended,
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memory_order_acquire,
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memory_order_relaxed))) {
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return 0;
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}
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return EBUSY;
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}
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/*
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* Lock a mutex of type NORMAL.
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@ -290,25 +303,17 @@ int pthread_mutex_init(pthread_mutex_t* mutex, const pthread_mutexattr_t* attr)
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* "type" value is zero, so the only bits that will be set are the ones in
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* the lock state field.
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*/
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static inline void _normal_mutex_lock(atomic_int* mutex_value_ptr, int shared) {
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/* convenience shortcuts */
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const int unlocked = shared | MUTEX_STATE_BITS_UNLOCKED;
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const int locked_uncontended = shared | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
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// The common case is an unlocked mutex, so we begin by trying to
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// change the lock's state from unlocked to locked_uncontended.
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// If exchanged successfully, An acquire fence is required to make
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// all memory accesses made by other threads visible in current CPU.
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int mvalue = unlocked;
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if (__predict_true(atomic_compare_exchange_strong_explicit(mutex_value_ptr, &mvalue,
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locked_uncontended,
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memory_order_acquire,
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memory_order_relaxed))) {
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return;
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static inline int __pthread_normal_mutex_lock(atomic_int* mutex_value_ptr, int shared,
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const timespec* abs_timeout_or_null, clockid_t clock) {
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if (__predict_true(__normal_mutex_trylock(mutex_value_ptr, shared) == 0)) {
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return 0;
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}
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ScopedTrace trace("Contending for pthread mutex");
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const int unlocked = shared | MUTEX_STATE_BITS_UNLOCKED;
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const int locked_contended = shared | MUTEX_STATE_BITS_LOCKED_CONTENDED;
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// We want to go to sleep until the mutex is available, which requires
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// promoting it to locked_contended. We need to swap in the new state
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// value and then wait until somebody wakes us up.
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@ -316,20 +321,29 @@ static inline void _normal_mutex_lock(atomic_int* mutex_value_ptr, int shared) {
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// If it returns unlocked, we have acquired the lock, otherwise another
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// thread still holds the lock and we should wait again.
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// If lock is acquired, an acquire fence is needed to make all memory accesses
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// made by other threads visible in current CPU.
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const int locked_contended = shared | MUTEX_STATE_BITS_LOCKED_CONTENDED;
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// made by other threads visible to the current CPU.
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while (atomic_exchange_explicit(mutex_value_ptr, locked_contended,
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memory_order_acquire) != unlocked) {
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__futex_wait_ex(mutex_value_ptr, shared, locked_contended, NULL);
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timespec ts;
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timespec* rel_timeout = NULL;
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if (abs_timeout_or_null != NULL) {
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rel_timeout = &ts;
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if (!timespec_from_absolute_timespec(*rel_timeout, *abs_timeout_or_null, clock)) {
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return ETIMEDOUT;
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}
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}
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if (__futex_wait_ex(mutex_value_ptr, shared, locked_contended, rel_timeout) == -ETIMEDOUT) {
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return ETIMEDOUT;
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}
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}
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return 0;
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}
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/*
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* Release a mutex of type NORMAL. The caller is responsible for determining
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* that we are in fact the owner of this lock.
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*/
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static inline void _normal_mutex_unlock(atomic_int* mutex_value_ptr, int shared) {
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static inline void __pthread_normal_mutex_unlock(atomic_int* mutex_value_ptr, int shared) {
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const int unlocked = shared | MUTEX_STATE_BITS_UNLOCKED;
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const int locked_contended = shared | MUTEX_STATE_BITS_LOCKED_CONTENDED;
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@ -362,25 +376,13 @@ static inline void _normal_mutex_unlock(atomic_int* mutex_value_ptr, int shared)
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}
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}
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/* This common inlined function is used to increment the counter of an
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* errorcheck or recursive mutex.
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/* This common inlined function is used to increment the counter of a recursive mutex.
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*
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* For errorcheck mutexes, it will return EDEADLK
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* If the counter overflows, it will return EAGAIN
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* Otherwise, it atomically increments the counter and returns 0
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* after providing an acquire barrier.
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* If the counter overflows, it will return EAGAIN.
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* Otherwise, it atomically increments the counter and returns 0.
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*
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* mtype is the current mutex type
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* mvalue is the current mutex value (already loaded)
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* mutex pointers to the mutex.
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*/
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static inline __always_inline
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int _recursive_increment(atomic_int* mutex_value_ptr, int mvalue, int mtype) {
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if (mtype == MUTEX_TYPE_BITS_ERRORCHECK) {
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// Trying to re-lock a mutex we already acquired.
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return EDEADLK;
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}
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static inline int __recursive_increment(atomic_int* mutex_value_ptr, int mvalue) {
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// Detect recursive lock overflow and return EAGAIN.
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// This is safe because only the owner thread can modify the
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// counter bits in the mutex value.
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@ -393,15 +395,13 @@ int _recursive_increment(atomic_int* mutex_value_ptr, int mvalue, int mtype) {
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// loop to update the counter. The counter will not overflow in the loop,
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// as only the owner thread can change it.
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// The mutex is still locked, so we don't need a release fence.
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while (!atomic_compare_exchange_weak_explicit(mutex_value_ptr, &mvalue,
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mvalue + MUTEX_COUNTER_BITS_ONE,
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memory_order_relaxed,
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memory_order_relaxed)) { }
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atomic_fetch_add_explicit(mutex_value_ptr, MUTEX_COUNTER_BITS_ONE, memory_order_relaxed);
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return 0;
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}
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int pthread_mutex_lock(pthread_mutex_t* mutex) {
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atomic_int* mutex_value_ptr = MUTEX_TO_ATOMIC_POINTER(mutex);
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static int __pthread_mutex_lock_with_timeout(pthread_mutex_t* mutex,
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const timespec* abs_timeout_or_null, clockid_t clock) {
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atomic_int* mutex_value_ptr = get_mutex_value_pointer(mutex);
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int mvalue, mtype, tid, shared;
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@ -411,24 +411,28 @@ int pthread_mutex_lock(pthread_mutex_t* mutex) {
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// Handle common case first.
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if ( __predict_true(mtype == MUTEX_TYPE_BITS_NORMAL) ) {
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_normal_mutex_lock(mutex_value_ptr, shared);
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return 0;
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return __pthread_normal_mutex_lock(mutex_value_ptr, shared, abs_timeout_or_null, clock);
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}
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// Do we already own this recursive or error-check mutex?
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tid = __get_thread()->tid;
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if ( tid == MUTEX_OWNER_FROM_BITS(mvalue) )
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return _recursive_increment(mutex_value_ptr, mvalue, mtype);
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if (tid == MUTEX_OWNER_FROM_BITS(mvalue)) {
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if (mtype == MUTEX_TYPE_BITS_ERRORCHECK) {
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return EDEADLK;
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}
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return __recursive_increment(mutex_value_ptr, mvalue);
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}
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// Add in shared state to avoid extra 'or' operations below.
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mtype |= shared;
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const int unlocked = mtype | shared | MUTEX_STATE_BITS_UNLOCKED;
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const int locked_uncontended = mtype | shared | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
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const int locked_contended = mtype | shared | MUTEX_STATE_BITS_LOCKED_CONTENDED;
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// First, if the mutex is unlocked, try to quickly acquire it.
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// In the optimistic case where this works, set the state to locked_uncontended.
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if (mvalue == mtype) {
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int newval = MUTEX_OWNER_TO_BITS(tid) | mtype | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
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// If exchanged successfully, An acquire fence is required to make
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// all memory accesses made by other threads visible in current CPU.
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if (mvalue == unlocked) {
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int newval = MUTEX_OWNER_TO_BITS(tid) | locked_uncontended;
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// If exchanged successfully, an acquire fence is required to make
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// all memory accesses made by other threads visible to the current CPU.
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if (__predict_true(atomic_compare_exchange_strong_explicit(mutex_value_ptr, &mvalue,
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newval, memory_order_acquire, memory_order_relaxed))) {
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return 0;
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@ -438,16 +442,14 @@ int pthread_mutex_lock(pthread_mutex_t* mutex) {
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ScopedTrace trace("Contending for pthread mutex");
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while (true) {
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if (mvalue == mtype) {
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// If the mutex is unlocked, its value should be 'mtype' and
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// we try to acquire it by setting its owner and state atomically.
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if (mvalue == unlocked) {
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// NOTE: We put the state to locked_contended since we _know_ there
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// is contention when we are in this loop. This ensures all waiters
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// will be unlocked.
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int newval = MUTEX_OWNER_TO_BITS(tid) | mtype | MUTEX_STATE_BITS_LOCKED_CONTENDED;
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// If exchanged successfully, An acquire fence is required to make
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// all memory accesses made by other threads visible in current CPU.
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int newval = MUTEX_OWNER_TO_BITS(tid) | locked_contended;
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// If exchanged successfully, an acquire fence is required to make
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// all memory accesses made by other threads visible to the current CPU.
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if (__predict_true(atomic_compare_exchange_weak_explicit(mutex_value_ptr,
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&mvalue, newval,
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memory_order_acquire,
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@ -456,8 +458,7 @@ int pthread_mutex_lock(pthread_mutex_t* mutex) {
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}
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continue;
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} else if (MUTEX_STATE_BITS_IS_LOCKED_UNCONTENDED(mvalue)) {
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// The mutex is already locked by another thread, if the state is locked_uncontended,
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// we should set it to locked_contended beforing going to sleep. This can make
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// We should set it to locked_contended beforing going to sleep. This can make
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// sure waiters will be woken up eventually.
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int newval = MUTEX_STATE_BITS_FLIP_CONTENTION(mvalue);
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@ -470,14 +471,39 @@ int pthread_mutex_lock(pthread_mutex_t* mutex) {
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mvalue = newval;
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}
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// We are in locked_contended state, sleep until someone wake us up.
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__futex_wait_ex(mutex_value_ptr, shared, mvalue, NULL);
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// We are in locked_contended state, sleep until someone wakes us up.
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timespec ts;
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timespec* rel_timeout = NULL;
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if (abs_timeout_or_null != NULL) {
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rel_timeout = &ts;
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if (!timespec_from_absolute_timespec(*rel_timeout, *abs_timeout_or_null, clock)) {
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return ETIMEDOUT;
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}
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}
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if (__futex_wait_ex(mutex_value_ptr, shared, mvalue, rel_timeout) == -ETIMEDOUT) {
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return ETIMEDOUT;
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}
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mvalue = atomic_load_explicit(mutex_value_ptr, memory_order_relaxed);
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}
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}
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int pthread_mutex_lock(pthread_mutex_t* mutex) {
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atomic_int* mutex_value_ptr = get_mutex_value_pointer(mutex);
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int mvalue = atomic_load_explicit(mutex_value_ptr, memory_order_relaxed);
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int mtype = (mvalue & MUTEX_TYPE_MASK);
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int shared = (mvalue & MUTEX_SHARED_MASK);
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// Avoid slowing down fast path of normal mutex lock operation.
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if (__predict_true(mtype == MUTEX_TYPE_BITS_NORMAL)) {
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if (__predict_true(__pthread_normal_mutex_trylock(mutex_value_ptr, shared) == 0)) {
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return 0;
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}
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}
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return __pthread_mutex_lock_with_timeout(mutex, NULL, 0);
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}
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int pthread_mutex_unlock(pthread_mutex_t* mutex) {
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atomic_int* mutex_value_ptr = MUTEX_TO_ATOMIC_POINTER(mutex);
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atomic_int* mutex_value_ptr = get_mutex_value_pointer(mutex);
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int mvalue, mtype, tid, shared;
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@ -487,7 +513,7 @@ int pthread_mutex_unlock(pthread_mutex_t* mutex) {
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// Handle common case first.
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if (__predict_true(mtype == MUTEX_TYPE_BITS_NORMAL)) {
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_normal_mutex_unlock(mutex_value_ptr, shared);
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__pthread_normal_mutex_unlock(mutex_value_ptr, shared);
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return 0;
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}
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@ -501,10 +527,7 @@ int pthread_mutex_unlock(pthread_mutex_t* mutex) {
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// lower state bits), use a compare_exchange loop to do it.
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if (!MUTEX_COUNTER_BITS_IS_ZERO(mvalue)) {
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// We still own the mutex, so a release fence is not needed.
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while (!atomic_compare_exchange_weak_explicit(mutex_value_ptr, &mvalue,
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mvalue - MUTEX_COUNTER_BITS_ONE,
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memory_order_relaxed,
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memory_order_relaxed)) { }
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atomic_fetch_sub_explicit(mutex_value_ptr, MUTEX_COUNTER_BITS_ONE, memory_order_relaxed);
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return 0;
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}
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@ -514,9 +537,8 @@ int pthread_mutex_unlock(pthread_mutex_t* mutex) {
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// to awake.
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// A release fence is required to make previous stores visible to next
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// lock owner threads.
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mvalue = atomic_exchange_explicit(mutex_value_ptr,
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mtype | shared | MUTEX_STATE_BITS_UNLOCKED,
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memory_order_release);
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const int unlocked = mtype | shared | MUTEX_STATE_BITS_UNLOCKED;
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mvalue = atomic_exchange_explicit(mutex_value_ptr, unlocked, memory_order_release);
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if (MUTEX_STATE_BITS_IS_LOCKED_CONTENDED(mvalue)) {
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__futex_wake_ex(mutex_value_ptr, shared, 1);
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}
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@ -525,25 +547,18 @@ int pthread_mutex_unlock(pthread_mutex_t* mutex) {
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}
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int pthread_mutex_trylock(pthread_mutex_t* mutex) {
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atomic_int* mutex_value_ptr = MUTEX_TO_ATOMIC_POINTER(mutex);
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atomic_int* mutex_value_ptr = get_mutex_value_pointer(mutex);
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int mvalue = atomic_load_explicit(mutex_value_ptr, memory_order_relaxed);
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int mtype = (mvalue & MUTEX_TYPE_MASK);
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int shared = (mvalue & MUTEX_SHARED_MASK);
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const int unlocked = mtype | shared | MUTEX_STATE_BITS_UNLOCKED;
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const int locked_uncontended = mtype | shared | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
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// Handle common case first.
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if (__predict_true(mtype == MUTEX_TYPE_BITS_NORMAL)) {
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mvalue = shared | MUTEX_STATE_BITS_UNLOCKED;
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// If exchanged successfully, An acquire fence is required to make
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// all memory accesses made by other threads visible in current CPU.
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if (atomic_compare_exchange_strong_explicit(mutex_value_ptr,
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&mvalue,
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shared | MUTEX_STATE_BITS_LOCKED_UNCONTENDED,
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memory_order_acquire,
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memory_order_relaxed)) {
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return 0;
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}
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return EBUSY;
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return __pthread_normal_mutex_trylock(mutex_value_ptr, shared);
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}
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// Do we already own this recursive or error-check mutex?
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@ -552,19 +567,17 @@ int pthread_mutex_trylock(pthread_mutex_t* mutex) {
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if (mtype == MUTEX_TYPE_BITS_ERRORCHECK) {
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return EBUSY;
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}
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return _recursive_increment(mutex_value_ptr, mvalue, mtype);
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return __recursive_increment(mutex_value_ptr, mvalue);
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}
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// Same as pthread_mutex_lock, except that we don't want to wait, and
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// the only operation that can succeed is a single compare_exchange to acquire the
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// lock if it is released / not owned by anyone. No need for a complex loop.
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// If exchanged successfully, An acquire fence is required to make
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// all memory accesses made by other threads visible in current CPU.
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mtype |= shared | MUTEX_STATE_BITS_UNLOCKED;
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mvalue = MUTEX_OWNER_TO_BITS(tid) | mtype | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
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if (__predict_true(atomic_compare_exchange_strong_explicit(mutex_value_ptr,
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&mtype, mvalue,
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// If exchanged successfully, an acquire fence is required to make
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// all memory accesses made by other threads visible to the current CPU.
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mvalue = unlocked;
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int newval = MUTEX_OWNER_TO_BITS(tid) | locked_uncontended;
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if (__predict_true(atomic_compare_exchange_strong_explicit(mutex_value_ptr, &mvalue, newval,
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memory_order_acquire,
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memory_order_relaxed))) {
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return 0;
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@ -572,112 +585,6 @@ int pthread_mutex_trylock(pthread_mutex_t* mutex) {
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return EBUSY;
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}
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static int __pthread_mutex_timedlock(pthread_mutex_t* mutex, const timespec* abs_ts, clockid_t clock) {
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atomic_int* mutex_value_ptr = MUTEX_TO_ATOMIC_POINTER(mutex);
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timespec ts;
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int mvalue = atomic_load_explicit(mutex_value_ptr, memory_order_relaxed);
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int mtype = (mvalue & MUTEX_TYPE_MASK);
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int shared = (mvalue & MUTEX_SHARED_MASK);
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// Handle common case first.
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if (__predict_true(mtype == MUTEX_TYPE_BITS_NORMAL)) {
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const int unlocked = shared | MUTEX_STATE_BITS_UNLOCKED;
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const int locked_uncontended = shared | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
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const int locked_contended = shared | MUTEX_STATE_BITS_LOCKED_CONTENDED;
|
||||
|
||||
// If exchanged successfully, An acquire fence is required to make
|
||||
// all memory accesses made by other threads visible in current CPU.
|
||||
mvalue = unlocked;
|
||||
if (atomic_compare_exchange_strong_explicit(mutex_value_ptr, &mvalue, locked_uncontended,
|
||||
memory_order_acquire, memory_order_relaxed)) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
ScopedTrace trace("Contending for timed pthread mutex");
|
||||
|
||||
// Same as pthread_mutex_lock, except that we can only wait for a specified
|
||||
// time interval. If lock is acquired, an acquire fence is needed to make
|
||||
// all memory accesses made by other threads visible in current CPU.
|
||||
while (atomic_exchange_explicit(mutex_value_ptr, locked_contended,
|
||||
memory_order_acquire) != unlocked) {
|
||||
if (!timespec_from_absolute_timespec(ts, *abs_ts, clock)) {
|
||||
return ETIMEDOUT;
|
||||
}
|
||||
__futex_wait_ex(mutex_value_ptr, shared, locked_contended, &ts);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
// Do we already own this recursive or error-check mutex?
|
||||
pid_t tid = __get_thread()->tid;
|
||||
if (tid == MUTEX_OWNER_FROM_BITS(mvalue)) {
|
||||
return _recursive_increment(mutex_value_ptr, mvalue, mtype);
|
||||
}
|
||||
|
||||
mtype |= shared;
|
||||
|
||||
// First try a quick lock.
|
||||
if (mvalue == mtype) {
|
||||
int newval = MUTEX_OWNER_TO_BITS(tid) | mtype | MUTEX_STATE_BITS_LOCKED_UNCONTENDED;
|
||||
// If exchanged successfully, An acquire fence is required to make
|
||||
// all memory accesses made by other threads visible in current CPU.
|
||||
if (__predict_true(atomic_compare_exchange_strong_explicit(mutex_value_ptr,
|
||||
&mvalue, newval,
|
||||
memory_order_acquire,
|
||||
memory_order_relaxed))) {
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
ScopedTrace trace("Contending for timed pthread mutex");
|
||||
|
||||
// The following implements the same loop as pthread_mutex_lock,
|
||||
// but adds checks to ensure that the operation never exceeds the
|
||||
// absolute expiration time.
|
||||
while (true) {
|
||||
if (mvalue == mtype) { // Unlocked.
|
||||
int newval = MUTEX_OWNER_TO_BITS(tid) | mtype | MUTEX_STATE_BITS_LOCKED_CONTENDED;
|
||||
// An acquire fence is needed for successful exchange.
|
||||
if (!atomic_compare_exchange_strong_explicit(mutex_value_ptr, &mvalue, newval,
|
||||
memory_order_acquire,
|
||||
memory_order_relaxed)) {
|
||||
goto check_time;
|
||||
}
|
||||
|
||||
return 0;
|
||||
} else if (MUTEX_STATE_BITS_IS_LOCKED_UNCONTENDED(mvalue)) {
|
||||
// The value is locked. If the state is locked_uncontended, we need to switch
|
||||
// it to locked_contended before sleep, so we can get woken up later.
|
||||
int newval = MUTEX_STATE_BITS_FLIP_CONTENTION(mvalue);
|
||||
if (!atomic_compare_exchange_strong_explicit(mutex_value_ptr, &mvalue, newval,
|
||||
memory_order_relaxed,
|
||||
memory_order_relaxed)) {
|
||||
goto check_time;
|
||||
}
|
||||
mvalue = newval;
|
||||
}
|
||||
|
||||
if (!timespec_from_absolute_timespec(ts, *abs_ts, clock)) {
|
||||
return ETIMEDOUT;
|
||||
}
|
||||
|
||||
if (__futex_wait_ex(mutex_value_ptr, shared, mvalue, &ts) == -ETIMEDOUT) {
|
||||
return ETIMEDOUT;
|
||||
}
|
||||
|
||||
check_time:
|
||||
if (!timespec_from_absolute_timespec(ts, *abs_ts, clock)) {
|
||||
return ETIMEDOUT;
|
||||
}
|
||||
// After futex_wait or time costly timespec_from_absolte_timespec,
|
||||
// we'd better read mvalue again in case it is changed.
|
||||
mvalue = atomic_load_explicit(mutex_value_ptr, memory_order_relaxed);
|
||||
}
|
||||
}
|
||||
|
||||
#if !defined(__LP64__)
|
||||
extern "C" int pthread_mutex_lock_timeout_np(pthread_mutex_t* mutex, unsigned ms) {
|
||||
timespec abs_timeout;
|
||||
@ -689,7 +596,7 @@ extern "C" int pthread_mutex_lock_timeout_np(pthread_mutex_t* mutex, unsigned ms
|
||||
abs_timeout.tv_nsec -= NS_PER_S;
|
||||
}
|
||||
|
||||
int error = __pthread_mutex_timedlock(mutex, &abs_timeout, CLOCK_MONOTONIC);
|
||||
int error = __pthread_mutex_lock_with_timeout(mutex, &abs_timeout, CLOCK_MONOTONIC);
|
||||
if (error == ETIMEDOUT) {
|
||||
error = EBUSY;
|
||||
}
|
||||
@ -698,7 +605,7 @@ extern "C" int pthread_mutex_lock_timeout_np(pthread_mutex_t* mutex, unsigned ms
|
||||
#endif
|
||||
|
||||
int pthread_mutex_timedlock(pthread_mutex_t* mutex, const timespec* abs_timeout) {
|
||||
return __pthread_mutex_timedlock(mutex, abs_timeout, CLOCK_REALTIME);
|
||||
return __pthread_mutex_lock_with_timeout(mutex, abs_timeout, CLOCK_REALTIME);
|
||||
}
|
||||
|
||||
int pthread_mutex_destroy(pthread_mutex_t* mutex) {
|
||||
@ -708,7 +615,7 @@ int pthread_mutex_destroy(pthread_mutex_t* mutex) {
|
||||
return error;
|
||||
}
|
||||
|
||||
atomic_int* mutex_value_ptr = MUTEX_TO_ATOMIC_POINTER(mutex);
|
||||
atomic_int* mutex_value_ptr = get_mutex_value_pointer(mutex);
|
||||
atomic_store_explicit(mutex_value_ptr, 0xdead10cc, memory_order_relaxed);
|
||||
return 0;
|
||||
}
|
||||
|
@ -733,8 +733,10 @@ TEST(pthread, pthread_rwlock_reader_wakeup_writer) {
|
||||
pthread_t thread;
|
||||
ASSERT_EQ(0, pthread_create(&thread, NULL,
|
||||
reinterpret_cast<void* (*)(void*)>(pthread_rwlock_reader_wakeup_writer_helper), &wakeup_arg));
|
||||
sleep(1);
|
||||
ASSERT_EQ(RwlockWakeupHelperArg::LOCK_WAITING, wakeup_arg.progress);
|
||||
while (wakeup_arg.progress != RwlockWakeupHelperArg::LOCK_WAITING) {
|
||||
usleep(5000);
|
||||
}
|
||||
usleep(5000);
|
||||
wakeup_arg.progress = RwlockWakeupHelperArg::LOCK_RELEASED;
|
||||
ASSERT_EQ(0, pthread_rwlock_unlock(&wakeup_arg.lock));
|
||||
|
||||
@ -764,8 +766,10 @@ TEST(pthread, pthread_rwlock_writer_wakeup_reader) {
|
||||
pthread_t thread;
|
||||
ASSERT_EQ(0, pthread_create(&thread, NULL,
|
||||
reinterpret_cast<void* (*)(void*)>(pthread_rwlock_writer_wakeup_reader_helper), &wakeup_arg));
|
||||
sleep(1);
|
||||
ASSERT_EQ(RwlockWakeupHelperArg::LOCK_WAITING, wakeup_arg.progress);
|
||||
while (wakeup_arg.progress != RwlockWakeupHelperArg::LOCK_WAITING) {
|
||||
usleep(5000);
|
||||
}
|
||||
usleep(5000);
|
||||
wakeup_arg.progress = RwlockWakeupHelperArg::LOCK_RELEASED;
|
||||
ASSERT_EQ(0, pthread_rwlock_unlock(&wakeup_arg.lock));
|
||||
|
||||
@ -1118,15 +1122,21 @@ TEST(pthread, pthread_mutexattr_gettype) {
|
||||
ASSERT_EQ(0, pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE));
|
||||
ASSERT_EQ(0, pthread_mutexattr_gettype(&attr, &attr_type));
|
||||
ASSERT_EQ(PTHREAD_MUTEX_RECURSIVE, attr_type);
|
||||
|
||||
ASSERT_EQ(0, pthread_mutexattr_destroy(&attr));
|
||||
}
|
||||
|
||||
static void CreateMutex(pthread_mutex_t& mutex, int mutex_type) {
|
||||
pthread_mutexattr_t attr;
|
||||
ASSERT_EQ(0, pthread_mutexattr_init(&attr));
|
||||
ASSERT_EQ(0, pthread_mutexattr_settype(&attr, mutex_type));
|
||||
ASSERT_EQ(0, pthread_mutex_init(&mutex, &attr));
|
||||
ASSERT_EQ(0, pthread_mutexattr_destroy(&attr));
|
||||
}
|
||||
|
||||
TEST(pthread, pthread_mutex_lock_NORMAL) {
|
||||
pthread_mutexattr_t attr;
|
||||
ASSERT_EQ(0, pthread_mutexattr_init(&attr));
|
||||
ASSERT_EQ(0, pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_NORMAL));
|
||||
|
||||
pthread_mutex_t lock;
|
||||
ASSERT_EQ(0, pthread_mutex_init(&lock, &attr));
|
||||
CreateMutex(lock, PTHREAD_MUTEX_NORMAL);
|
||||
|
||||
ASSERT_EQ(0, pthread_mutex_lock(&lock));
|
||||
ASSERT_EQ(0, pthread_mutex_unlock(&lock));
|
||||
@ -1134,12 +1144,8 @@ TEST(pthread, pthread_mutex_lock_NORMAL) {
|
||||
}
|
||||
|
||||
TEST(pthread, pthread_mutex_lock_ERRORCHECK) {
|
||||
pthread_mutexattr_t attr;
|
||||
ASSERT_EQ(0, pthread_mutexattr_init(&attr));
|
||||
ASSERT_EQ(0, pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK));
|
||||
|
||||
pthread_mutex_t lock;
|
||||
ASSERT_EQ(0, pthread_mutex_init(&lock, &attr));
|
||||
CreateMutex(lock, PTHREAD_MUTEX_ERRORCHECK);
|
||||
|
||||
ASSERT_EQ(0, pthread_mutex_lock(&lock));
|
||||
ASSERT_EQ(EDEADLK, pthread_mutex_lock(&lock));
|
||||
@ -1152,12 +1158,8 @@ TEST(pthread, pthread_mutex_lock_ERRORCHECK) {
|
||||
}
|
||||
|
||||
TEST(pthread, pthread_mutex_lock_RECURSIVE) {
|
||||
pthread_mutexattr_t attr;
|
||||
ASSERT_EQ(0, pthread_mutexattr_init(&attr));
|
||||
ASSERT_EQ(0, pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE));
|
||||
|
||||
pthread_mutex_t lock;
|
||||
ASSERT_EQ(0, pthread_mutex_init(&lock, &attr));
|
||||
CreateMutex(lock, PTHREAD_MUTEX_RECURSIVE);
|
||||
|
||||
ASSERT_EQ(0, pthread_mutex_lock(&lock));
|
||||
ASSERT_EQ(0, pthread_mutex_lock(&lock));
|
||||
@ -1169,6 +1171,66 @@ TEST(pthread, pthread_mutex_lock_RECURSIVE) {
|
||||
ASSERT_EQ(0, pthread_mutex_destroy(&lock));
|
||||
}
|
||||
|
||||
class MutexWakeupHelper {
|
||||
private:
|
||||
pthread_mutex_t mutex;
|
||||
enum Progress {
|
||||
LOCK_INITIALIZED,
|
||||
LOCK_WAITING,
|
||||
LOCK_RELEASED,
|
||||
LOCK_ACCESSED
|
||||
};
|
||||
std::atomic<Progress> progress;
|
||||
|
||||
static void thread_fn(MutexWakeupHelper* helper) {
|
||||
ASSERT_EQ(LOCK_INITIALIZED, helper->progress);
|
||||
helper->progress = LOCK_WAITING;
|
||||
|
||||
ASSERT_EQ(0, pthread_mutex_lock(&helper->mutex));
|
||||
ASSERT_EQ(LOCK_RELEASED, helper->progress);
|
||||
ASSERT_EQ(0, pthread_mutex_unlock(&helper->mutex));
|
||||
|
||||
helper->progress = LOCK_ACCESSED;
|
||||
}
|
||||
|
||||
public:
|
||||
void test(int mutex_type) {
|
||||
CreateMutex(mutex, mutex_type);
|
||||
ASSERT_EQ(0, pthread_mutex_lock(&mutex));
|
||||
progress = LOCK_INITIALIZED;
|
||||
|
||||
pthread_t thread;
|
||||
ASSERT_EQ(0, pthread_create(&thread, NULL,
|
||||
reinterpret_cast<void* (*)(void*)>(MutexWakeupHelper::thread_fn), this));
|
||||
|
||||
while (progress != LOCK_WAITING) {
|
||||
usleep(5000);
|
||||
}
|
||||
usleep(5000);
|
||||
progress = LOCK_RELEASED;
|
||||
ASSERT_EQ(0, pthread_mutex_unlock(&mutex));
|
||||
|
||||
ASSERT_EQ(0, pthread_join(thread, NULL));
|
||||
ASSERT_EQ(LOCK_ACCESSED, progress);
|
||||
ASSERT_EQ(0, pthread_mutex_destroy(&mutex));
|
||||
}
|
||||
};
|
||||
|
||||
TEST(pthread, pthread_mutex_NORMAL_wakeup) {
|
||||
MutexWakeupHelper helper;
|
||||
helper.test(PTHREAD_MUTEX_NORMAL);
|
||||
}
|
||||
|
||||
TEST(pthread, pthread_mutex_ERRORCHECK_wakeup) {
|
||||
MutexWakeupHelper helper;
|
||||
helper.test(PTHREAD_MUTEX_ERRORCHECK);
|
||||
}
|
||||
|
||||
TEST(pthread, pthread_mutex_RECURSIVE_wakeup) {
|
||||
MutexWakeupHelper helper;
|
||||
helper.test(PTHREAD_MUTEX_RECURSIVE);
|
||||
}
|
||||
|
||||
TEST(pthread, pthread_mutex_owner_tid_limit) {
|
||||
FILE* fp = fopen("/proc/sys/kernel/pid_max", "r");
|
||||
ASSERT_TRUE(fp != NULL);
|
||||
|
Loading…
x
Reference in New Issue
Block a user