#include "qemu/event_notifier.h"
#include "block/thread-pool.h"
-typedef struct ThreadPool ThreadPool;
-
static void do_spawn_thread(ThreadPool *pool);
typedef struct ThreadPoolElement ThreadPoolElement;
struct ThreadPool {
EventNotifier notifier;
+ AioContext *ctx;
QemuMutex lock;
QemuCond check_cancel;
+ QemuCond worker_stopped;
QemuSemaphore sem;
int max_threads;
QEMUBH *new_thread_bh;
int new_threads; /* backlog of threads we need to create */
int pending_threads; /* threads created but not running yet */
int pending_cancellations; /* whether we need a cond_broadcast */
+ bool stopping;
};
-/* Currently there is only one thread pool instance. */
-static ThreadPool global_pool;
-
static void *worker_thread(void *opaque)
{
ThreadPool *pool = opaque;
pool->pending_threads--;
do_spawn_thread(pool);
- while (1) {
+ while (!pool->stopping) {
ThreadPoolElement *req;
int ret;
qemu_mutex_lock(&pool->lock);
pool->idle_threads--;
} while (ret == -1 && !QTAILQ_EMPTY(&pool->request_list));
- if (ret == -1) {
+ if (ret == -1 || pool->stopping) {
break;
}
}
pool->cur_threads--;
+ qemu_cond_signal(&pool->worker_stopped);
qemu_mutex_unlock(&pool->lock);
return NULL;
}
.cancel = thread_pool_cancel,
};
-BlockDriverAIOCB *thread_pool_submit_aio(ThreadPoolFunc *func, void *arg,
+BlockDriverAIOCB *thread_pool_submit_aio(ThreadPool *pool,
+ ThreadPoolFunc *func, void *arg,
BlockDriverCompletionFunc *cb, void *opaque)
{
- ThreadPool *pool = &global_pool;
ThreadPoolElement *req;
req = qemu_aio_get(&thread_pool_aiocb_info, NULL, cb, opaque);
qemu_coroutine_enter(co->co, NULL);
}
-int coroutine_fn thread_pool_submit_co(ThreadPoolFunc *func, void *arg)
+int coroutine_fn thread_pool_submit_co(ThreadPool *pool, ThreadPoolFunc *func,
+ void *arg)
{
ThreadPoolCo tpc = { .co = qemu_coroutine_self(), .ret = -EINPROGRESS };
assert(qemu_in_coroutine());
- thread_pool_submit_aio(func, arg, thread_pool_co_cb, &tpc);
+ thread_pool_submit_aio(pool, func, arg, thread_pool_co_cb, &tpc);
qemu_coroutine_yield();
return tpc.ret;
}
-void thread_pool_submit(ThreadPoolFunc *func, void *arg)
+void thread_pool_submit(ThreadPool *pool, ThreadPoolFunc *func, void *arg)
{
- thread_pool_submit_aio(func, arg, NULL, NULL);
+ thread_pool_submit_aio(pool, func, arg, NULL, NULL);
}
static void thread_pool_init_one(ThreadPool *pool, AioContext *ctx)
memset(pool, 0, sizeof(*pool));
event_notifier_init(&pool->notifier, false);
+ pool->ctx = ctx;
qemu_mutex_init(&pool->lock);
qemu_cond_init(&pool->check_cancel);
+ qemu_cond_init(&pool->worker_stopped);
qemu_sem_init(&pool->sem, 0);
pool->max_threads = 64;
pool->new_thread_bh = aio_bh_new(ctx, spawn_thread_bh_fn, pool);
thread_pool_active);
}
-static void thread_pool_init(void)
+ThreadPool *thread_pool_new(AioContext *ctx)
{
- thread_pool_init_one(&global_pool, NULL);
+ ThreadPool *pool = g_new(ThreadPool, 1);
+ thread_pool_init_one(pool, ctx);
+ return pool;
}
-block_init(thread_pool_init)
+void thread_pool_free(ThreadPool *pool)
+{
+ if (!pool) {
+ return;
+ }
+
+ assert(QLIST_EMPTY(&pool->head));
+
+ qemu_mutex_lock(&pool->lock);
+
+ /* Stop new threads from spawning */
+ qemu_bh_delete(pool->new_thread_bh);
+ pool->cur_threads -= pool->new_threads;
+ pool->new_threads = 0;
+
+ /* Wait for worker threads to terminate */
+ pool->stopping = true;
+ while (pool->cur_threads > 0) {
+ qemu_sem_post(&pool->sem);
+ qemu_cond_wait(&pool->worker_stopped, &pool->lock);
+ }
+
+ qemu_mutex_unlock(&pool->lock);
+
+ aio_set_event_notifier(pool->ctx, &pool->notifier, NULL, NULL);
+ qemu_sem_destroy(&pool->sem);
+ qemu_cond_destroy(&pool->check_cancel);
+ qemu_cond_destroy(&pool->worker_stopped);
+ qemu_mutex_destroy(&pool->lock);
+ event_notifier_cleanup(&pool->notifier);
+ g_free(pool);
+}