block: Don't poll in bdrv_set_aio_context()

The explicit aio_poll() call in bdrv_set_aio_context() was added in
commit c2b6428d38 as a workaround for bdrv_drain() failing to achieve
to actually quiesce everything (specifically the NBD client code to
switch AioContext).

Now that the NBD client has been fixed to complete this operation during
bdrv_drain(), we don't need the workaround any more.

It was wrong anyway: aio_poll() must always be run in the home thread of
the AioContext.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Kevin Wolf 2019-02-15 13:13:12 +01:00
parent 28e0b2d2e1
commit 6c75d761d0

View File

@ -5273,10 +5273,6 @@ void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context)
bdrv_parent_drained_begin(bs, NULL, false);
bdrv_drain(bs); /* ensure there are no in-flight requests */
while (aio_poll(ctx, false)) {
/* wait for all bottom halves to execute */
}
bdrv_detach_aio_context(bs);
/* This function executes in the old AioContext so acquire the new one in