From 4feeec7e23b4151c962cb1b9f1a0e403803dfaee Mon Sep 17 00:00:00 2001 From: Hanna Reitz Date: Wed, 6 Oct 2021 17:19:37 +0200 Subject: [PATCH] mirror: Check job_is_cancelled() earlier We must check whether the job is force-cancelled early in our main loop, most importantly before any `continue` statement. For example, we used to have `continue`s before our current checking location that are triggered by `mirror_flush()` failing. So, if `mirror_flush()` kept failing, force-cancelling the job would not terminate it. Jobs can be cancelled while they yield, and once they are (force-cancelled), they should not generate new I/O requests. Therefore, we should put the check after the last yield before mirror_iteration() is invoked. Buglink: https://gitlab.com/qemu-project/qemu/-/issues/462 Signed-off-by: Hanna Reitz Reviewed-by: Eric Blake Reviewed-by: Vladimir Sementsov-Ogievskiy Message-Id: <20211006151940.214590-11-hreitz@redhat.com> Signed-off-by: Vladimir Sementsov-Ogievskiy --- block/mirror.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index 0eaba88060..3393ede0e1 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -1007,6 +1007,11 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) job_pause_point(&s->common.job); + if (job_is_cancelled(&s->common.job)) { + ret = 0; + goto immediate_exit; + } + cnt = bdrv_get_dirty_count(s->dirty_bitmap); /* cnt is the number of dirty bytes remaining and s->bytes_in_flight is * the number of bytes currently being processed; together those are @@ -1085,8 +1090,6 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) break; } - ret = 0; - if (job_is_ready(&s->common.job) && !should_complete) { delay_ns = (s->in_flight == 0 && cnt == 0 ? BLOCK_JOB_SLICE_TIME : 0); @@ -1094,9 +1097,6 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) trace_mirror_before_sleep(s, cnt, job_is_ready(&s->common.job), delay_ns); job_sleep_ns(&s->common.job, delay_ns); - if (job_is_cancelled(&s->common.job)) { - break; - } s->last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); }