block: Move bdrv_drain_all_begin() out of coroutine context

Before we can introduce a single polling loop for all nodes in
bdrv_drain_all_begin(), we must make sure to run it outside of coroutine
context like we already do for bdrv_do_drained_begin().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2018-04-10 16:07:55 +02:00
parent 4d22bbf4ef
commit c8ca33d06d

View File

@ -264,11 +264,16 @@ static void bdrv_co_drain_bh_cb(void *opaque)
Coroutine *co = data->co;
BlockDriverState *bs = data->bs;
bdrv_dec_in_flight(bs);
if (data->begin) {
bdrv_do_drained_begin(bs, data->recursive, data->parent, data->poll);
if (bs) {
bdrv_dec_in_flight(bs);
if (data->begin) {
bdrv_do_drained_begin(bs, data->recursive, data->parent, data->poll);
} else {
bdrv_do_drained_end(bs, data->recursive, data->parent);
}
} else {
bdrv_do_drained_end(bs, data->recursive, data->parent);
assert(data->begin);
bdrv_drain_all_begin();
}
data->done = true;
@ -294,7 +299,9 @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs,
.parent = parent,
.poll = poll,
};
bdrv_inc_in_flight(bs);
if (bs) {
bdrv_inc_in_flight(bs);
}
aio_bh_schedule_oneshot(bdrv_get_aio_context(bs),
bdrv_co_drain_bh_cb, &data);
@ -464,6 +471,11 @@ void bdrv_drain_all_begin(void)
BlockDriverState *bs;
BdrvNextIterator it;
if (qemu_in_coroutine()) {
bdrv_co_yield_to_drain(NULL, true, false, NULL, true);
return;
}
/* BDRV_POLL_WHILE() for a node can only be called from its own I/O thread
* or the main loop AioContext. We potentially use BDRV_POLL_WHILE() on
* nodes in several different AioContexts, so make sure we're in the main