diff options
Diffstat (limited to 'qemu-coroutine-lock.c')
-rw-r--r-- | qemu-coroutine-lock.c | 55 |
1 files changed, 38 insertions, 17 deletions
diff --git a/qemu-coroutine-lock.c b/qemu-coroutine-lock.c index 97ef01c796..86efe1f86a 100644 --- a/qemu-coroutine-lock.c +++ b/qemu-coroutine-lock.c @@ -29,28 +29,36 @@ #include "block/aio.h" #include "trace.h" -static QTAILQ_HEAD(, Coroutine) unlock_bh_queue = - QTAILQ_HEAD_INITIALIZER(unlock_bh_queue); -static QEMUBH* unlock_bh; +/* Coroutines are awoken from a BH to allow the current coroutine to complete + * its flow of execution. The BH may run after the CoQueue has been destroyed, + * so keep BH data in a separate heap-allocated struct. + */ +typedef struct { + QEMUBH *bh; + QTAILQ_HEAD(, Coroutine) entries; +} CoQueueNextData; static void qemu_co_queue_next_bh(void *opaque) { + CoQueueNextData *data = opaque; Coroutine *next; trace_qemu_co_queue_next_bh(); - while ((next = QTAILQ_FIRST(&unlock_bh_queue))) { - QTAILQ_REMOVE(&unlock_bh_queue, next, co_queue_next); + while ((next = QTAILQ_FIRST(&data->entries))) { + QTAILQ_REMOVE(&data->entries, next, co_queue_next); qemu_coroutine_enter(next, NULL); } + + qemu_bh_delete(data->bh); + g_slice_free(CoQueueNextData, data); } void qemu_co_queue_init(CoQueue *queue) { QTAILQ_INIT(&queue->entries); - if (!unlock_bh) { - unlock_bh = qemu_bh_new(qemu_co_queue_next_bh, NULL); - } + /* This will be exposed to callers once there are multiple AioContexts */ + queue->ctx = qemu_get_aio_context(); } void coroutine_fn qemu_co_queue_wait(CoQueue *queue) @@ -69,26 +77,39 @@ void coroutine_fn qemu_co_queue_wait_insert_head(CoQueue *queue) assert(qemu_in_coroutine()); } -bool qemu_co_queue_next(CoQueue *queue) +static bool qemu_co_queue_do_restart(CoQueue *queue, bool single) { Coroutine *next; + CoQueueNextData *data; + + if (QTAILQ_EMPTY(&queue->entries)) { + return false; + } - next = QTAILQ_FIRST(&queue->entries); - if (next) { + data = g_slice_new(CoQueueNextData); + data->bh = aio_bh_new(queue->ctx, qemu_co_queue_next_bh, data); + QTAILQ_INIT(&data->entries); + qemu_bh_schedule(data->bh); + + while ((next = QTAILQ_FIRST(&queue->entries)) != NULL) { QTAILQ_REMOVE(&queue->entries, next, co_queue_next); - QTAILQ_INSERT_TAIL(&unlock_bh_queue, next, co_queue_next); + QTAILQ_INSERT_TAIL(&data->entries, next, co_queue_next); trace_qemu_co_queue_next(next); - qemu_bh_schedule(unlock_bh); + if (single) { + break; + } } + return true; +} - return (next != NULL); +bool qemu_co_queue_next(CoQueue *queue) +{ + return qemu_co_queue_do_restart(queue, true); } void qemu_co_queue_restart_all(CoQueue *queue) { - while (qemu_co_queue_next(queue)) { - /* Do nothing */ - } + qemu_co_queue_do_restart(queue, false); } bool qemu_co_queue_empty(CoQueue *queue) |