The throttling code was segfaulting since commit 02ffb504485f0920cfc75a0982a602f824a9a4f4 because some qemu_co_queue_next caller does not run in a coroutine. qemu_co_queue_do_restart assume that the caller is a coroutinne. As sugested by Stefan fix this by entering the coroutine directly.
Signed-off-by: Benoit Canet <ben...@irqsave.net> --- block.c | 8 ++++---- include/block/coroutine.h | 5 +++++ qemu-coroutine-lock.c | 14 ++++++++++++++ 3 files changed, 23 insertions(+), 4 deletions(-) diff --git a/block.c b/block.c index b560241..dc72643 100644 --- a/block.c +++ b/block.c @@ -127,7 +127,8 @@ void bdrv_io_limits_disable(BlockDriverState *bs) { bs->io_limits_enabled = false; - while (qemu_co_queue_next(&bs->throttled_reqs)); + while (qemu_co_enter_next(&bs->throttled_reqs)) { + } if (bs->block_timer) { qemu_del_timer(bs->block_timer); @@ -143,7 +144,7 @@ static void bdrv_block_timer(void *opaque) { BlockDriverState *bs = opaque; - qemu_co_queue_next(&bs->throttled_reqs); + qemu_co_enter_next(&bs->throttled_reqs); } void bdrv_io_limits_enable(BlockDriverState *bs) @@ -1445,8 +1446,7 @@ void bdrv_drain_all(void) * a busy wait. */ QTAILQ_FOREACH(bs, &bdrv_states, list) { - if (!qemu_co_queue_empty(&bs->throttled_reqs)) { - qemu_co_queue_restart_all(&bs->throttled_reqs); + while (qemu_co_enter_next(&bs->throttled_reqs)) { busy = true; } } diff --git a/include/block/coroutine.h b/include/block/coroutine.h index 377805a..66e331c 100644 --- a/include/block/coroutine.h +++ b/include/block/coroutine.h @@ -138,6 +138,11 @@ bool qemu_co_queue_next(CoQueue *queue); void qemu_co_queue_restart_all(CoQueue *queue); /** + * Enter the next coroutine in the queue + */ +bool qemu_co_enter_next(CoQueue *queue); + +/** * Checks if the CoQueue is empty. */ bool qemu_co_queue_empty(CoQueue *queue); diff --git a/qemu-coroutine-lock.c b/qemu-coroutine-lock.c index d9fea49..c61d300 100644 --- a/qemu-coroutine-lock.c +++ b/qemu-coroutine-lock.c @@ -98,6 +98,20 @@ void qemu_co_queue_restart_all(CoQueue *queue) qemu_co_queue_do_restart(queue, false); } +bool qemu_co_enter_next(CoQueue *queue) +{ + Coroutine *next; + + next = QTAILQ_FIRST(&queue->entries); + if (!next) { + return false; + } + + QTAILQ_REMOVE(&queue->entries, next, co_queue_next); + qemu_coroutine_enter(next, NULL); + return true; +} + bool qemu_co_queue_empty(CoQueue *queue) { return (QTAILQ_FIRST(&queue->entries) == NULL); -- 1.7.10.4