From e680cfa7e20f5049c475ac94f998a79c9997b48d Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Wed, 13 Jul 2011 15:42:52 +0200 Subject: [PATCH] coroutines: Use one global bottom half for CoQueue Now that AsyncContexts don't exist any more, we can use one global bottom half for restarting coroutines instead of allocating a new one every time (before removing AsyncContexts, the problem with having a global BH was that it had to belong to a single AsyncContexts and wouldn't be executed in a different one - which leads to deadlocks) Signed-off-by: Kevin Wolf --- qemu-coroutine-lock.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) diff --git a/qemu-coroutine-lock.c b/qemu-coroutine-lock.c index abaa1f7967..a80f437c59 100644 --- a/qemu-coroutine-lock.c +++ b/qemu-coroutine-lock.c @@ -30,14 +30,10 @@ static QTAILQ_HEAD(, Coroutine) unlock_bh_queue = QTAILQ_HEAD_INITIALIZER(unlock_bh_queue); - -struct unlock_bh { - QEMUBH *bh; -}; +static QEMUBH* unlock_bh; static void qemu_co_queue_next_bh(void *opaque) { - struct unlock_bh *unlock_bh = opaque; Coroutine *next; trace_qemu_co_queue_next_bh(); @@ -45,14 +41,15 @@ static void qemu_co_queue_next_bh(void *opaque) QTAILQ_REMOVE(&unlock_bh_queue, next, co_queue_next); qemu_coroutine_enter(next, NULL); } - - qemu_bh_delete(unlock_bh->bh); - qemu_free(unlock_bh); } 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); + } } void coroutine_fn qemu_co_queue_wait(CoQueue *queue) @@ -65,7 +62,6 @@ void coroutine_fn qemu_co_queue_wait(CoQueue *queue) bool qemu_co_queue_next(CoQueue *queue) { - struct unlock_bh *unlock_bh; Coroutine *next; next = QTAILQ_FIRST(&queue->entries); @@ -73,10 +69,7 @@ bool qemu_co_queue_next(CoQueue *queue) QTAILQ_REMOVE(&queue->entries, next, co_queue_next); QTAILQ_INSERT_TAIL(&unlock_bh_queue, next, co_queue_next); trace_qemu_co_queue_next(next); - - unlock_bh = qemu_malloc(sizeof(*unlock_bh)); - unlock_bh->bh = qemu_bh_new(qemu_co_queue_next_bh, unlock_bh); - qemu_bh_schedule(unlock_bh->bh); + qemu_bh_schedule(unlock_bh); } return (next != NULL);