diff options
Diffstat (limited to 'util')
-rw-r--r-- | util/Makefile.objs | 1 | ||||
-rw-r--r-- | util/qemu-thread-posix.c | 14 | ||||
-rw-r--r-- | util/qemu-thread-win32.c | 25 | ||||
-rw-r--r-- | util/rfifolock.c | 78 |
4 files changed, 39 insertions, 79 deletions
diff --git a/util/Makefile.objs b/util/Makefile.objs index 36c7dcc1fa..ad0f9c7fe4 100644 --- a/util/Makefile.objs +++ b/util/Makefile.objs @@ -25,7 +25,6 @@ util-obj-y += uuid.o util-obj-y += throttle.o util-obj-y += getauxval.o util-obj-y += readline.o -util-obj-y += rfifolock.o util-obj-y += rcu.o util-obj-y += qemu-coroutine.o qemu-coroutine-lock.o qemu-coroutine-io.o util-obj-y += qemu-coroutine-sleep.o diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c index ce51b37c1d..d20cddec0c 100644 --- a/util/qemu-thread-posix.c +++ b/util/qemu-thread-posix.c @@ -80,6 +80,20 @@ void qemu_mutex_unlock(QemuMutex *mutex) error_exit(err, __func__); } +void qemu_rec_mutex_init(QemuRecMutex *mutex) +{ + int err; + pthread_mutexattr_t attr; + + pthread_mutexattr_init(&attr); + pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); + err = pthread_mutex_init(&mutex->lock, &attr); + pthread_mutexattr_destroy(&attr); + if (err) { + error_exit(err, __func__); + } +} + void qemu_cond_init(QemuCond *cond) { int err; diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c index 072806f792..728e76b5b2 100644 --- a/util/qemu-thread-win32.c +++ b/util/qemu-thread-win32.c @@ -79,6 +79,31 @@ void qemu_mutex_unlock(QemuMutex *mutex) LeaveCriticalSection(&mutex->lock); } +void qemu_rec_mutex_init(QemuRecMutex *mutex) +{ + InitializeCriticalSection(&mutex->lock); +} + +void qemu_rec_mutex_destroy(QemuRecMutex *mutex) +{ + DeleteCriticalSection(&mutex->lock); +} + +void qemu_rec_mutex_lock(QemuRecMutex *mutex) +{ + EnterCriticalSection(&mutex->lock); +} + +int qemu_rec_mutex_trylock(QemuRecMutex *mutex) +{ + return !TryEnterCriticalSection(&mutex->lock); +} + +void qemu_rec_mutex_unlock(QemuRecMutex *mutex) +{ + LeaveCriticalSection(&mutex->lock); +} + void qemu_cond_init(QemuCond *cond) { memset(cond, 0, sizeof(*cond)); diff --git a/util/rfifolock.c b/util/rfifolock.c deleted file mode 100644 index 084c2f0ea1..0000000000 --- a/util/rfifolock.c +++ /dev/null @@ -1,78 +0,0 @@ -/* - * Recursive FIFO lock - * - * Copyright Red Hat, Inc. 2013 - * - * Authors: - * Stefan Hajnoczi <stefanha@redhat.com> - * - * This work is licensed under the terms of the GNU LGPL, version 2 or later. - * See the COPYING.LIB file in the top-level directory. - * - */ - -#include "qemu/osdep.h" -#include "qemu/rfifolock.h" - -void rfifolock_init(RFifoLock *r, void (*cb)(void *), void *opaque) -{ - qemu_mutex_init(&r->lock); - r->head = 0; - r->tail = 0; - qemu_cond_init(&r->cond); - r->nesting = 0; - r->cb = cb; - r->cb_opaque = opaque; -} - -void rfifolock_destroy(RFifoLock *r) -{ - qemu_cond_destroy(&r->cond); - qemu_mutex_destroy(&r->lock); -} - -/* - * Theory of operation: - * - * In order to ensure FIFO ordering, implement a ticketlock. Threads acquiring - * the lock enqueue themselves by incrementing the tail index. When the lock - * is unlocked, the head is incremented and waiting threads are notified. - * - * Recursive locking does not take a ticket since the head is only incremented - * when the outermost recursive caller unlocks. - */ -void rfifolock_lock(RFifoLock *r) -{ - qemu_mutex_lock(&r->lock); - - /* Take a ticket */ - unsigned int ticket = r->tail++; - - if (r->nesting > 0 && qemu_thread_is_self(&r->owner_thread)) { - r->tail--; /* put ticket back, we're nesting */ - } else { - while (ticket != r->head) { - /* Invoke optional contention callback */ - if (r->cb) { - r->cb(r->cb_opaque); - } - qemu_cond_wait(&r->cond, &r->lock); - } - qemu_thread_get_self(&r->owner_thread); - } - - r->nesting++; - qemu_mutex_unlock(&r->lock); -} - -void rfifolock_unlock(RFifoLock *r) -{ - qemu_mutex_lock(&r->lock); - assert(r->nesting > 0); - assert(qemu_thread_is_self(&r->owner_thread)); - if (--r->nesting == 0) { - r->head++; - qemu_cond_broadcast(&r->cond); - } - qemu_mutex_unlock(&r->lock); -} |