changeset: 77576:dfc7fd24983a user: Kristjan Valur Jonsson date: Fri Jun 22 18:40:02 2012 +0000 files: Modules/_threadmodule.c description: Issue #15124: Optimize _thread.LockType deletion and acquisition when not contested, similar to what _thread.RLock already has. diff -r b9a6592c6250 -r dfc7fd24983a Modules/_threadmodule.c --- a/Modules/_threadmodule.c Fri Jun 22 14:11:58 2012 -0400 +++ b/Modules/_threadmodule.c Fri Jun 22 18:40:02 2012 +0000 @@ -23,6 +23,7 @@ PyObject_HEAD PyThread_type_lock lock_lock; PyObject *in_weakreflist; + char locked; /* for sanity checking */ } lockobject; static void @@ -32,9 +33,8 @@ PyObject_ClearWeakRefs((PyObject *) self); if (self->lock_lock != NULL) { /* Unlock the lock so it's safe to free it */ - PyThread_acquire_lock(self->lock_lock, 0); - PyThread_release_lock(self->lock_lock); - + if (self->locked) + PyThread_release_lock(self->lock_lock); PyThread_free_lock(self->lock_lock); } PyObject_Del(self); @@ -62,9 +62,13 @@ do { - Py_BEGIN_ALLOW_THREADS - r = PyThread_acquire_lock_timed(lock, microseconds, 1); - Py_END_ALLOW_THREADS + /* first a simple non-blocking try without releasing the GIL */ + r = PyThread_acquire_lock_timed(lock, 0, 0); + if (r == PY_LOCK_FAILURE && microseconds != 0) { + Py_BEGIN_ALLOW_THREADS + r = PyThread_acquire_lock_timed(lock, microseconds, 1); + Py_END_ALLOW_THREADS + } if (r == PY_LOCK_INTR) { /* Run signal handlers if we were interrupted. Propagate @@ -135,6 +139,8 @@ return NULL; } + if (r == PY_LOCK_ACQUIRED) + self->locked = 1; return PyBool_FromLong(r == PY_LOCK_ACQUIRED); } @@ -153,13 +159,13 @@ lock_PyThread_release_lock(lockobject *self) { /* Sanity check: the lock must be locked */ - if (PyThread_acquire_lock(self->lock_lock, 0)) { - PyThread_release_lock(self->lock_lock); + if (!self->locked) { PyErr_SetString(ThreadError, "release unlocked lock"); return NULL; } PyThread_release_lock(self->lock_lock); + self->locked = 0; Py_INCREF(Py_None); return Py_None; } @@ -175,11 +181,7 @@ static PyObject * lock_locked_lock(lockobject *self) { - if (PyThread_acquire_lock(self->lock_lock, 0)) { - PyThread_release_lock(self->lock_lock); - return PyBool_FromLong(0L); - } - return PyBool_FromLong(1L); + return PyBool_FromLong((long)self->locked); } PyDoc_STRVAR(locked_doc, @@ -313,14 +315,7 @@ self->rlock_count = count; Py_RETURN_TRUE; } - - if (self->rlock_count> 0 || - !PyThread_acquire_lock(self->rlock_lock, 0)) { - if (microseconds == 0) { - Py_RETURN_FALSE; - } - r = acquire_timed(self->rlock_lock, microseconds); - } + r = acquire_timed(self->rlock_lock, microseconds); if (r == PY_LOCK_ACQUIRED) { assert(self->rlock_count == 0); self->rlock_owner = tid; @@ -548,6 +543,7 @@ if (self == NULL) return NULL; self->lock_lock = PyThread_allocate_lock(); + self->locked = 0; self->in_weakreflist = NULL; if (self->lock_lock == NULL) { Py_DECREF(self);