diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2022-06-09 17:47:11 +0100 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2022-06-15 16:43:42 +0100 |
| commit | f387cac5af030a58ac5a0dacf64cab5e5a4fe5c7 (patch) | |
| tree | bb3ffcdbcf7184f2c1206e95e1723b2e2bb1d3e6 /block/linux-aio.c | |
| parent | 78e27dfa8d1c91171d49660aa50cbe6c424d41be (diff) | |
linux-aio: fix unbalanced plugged counter in laio_io_unplug()
Every laio_io_plug() call has a matching laio_io_unplug() call. There is
a plugged counter that tracks the number of levels of plugging and
allows for nesting.
The plugged counter must reflect the balance between laio_io_plug() and
laio_io_unplug() calls accurately. Otherwise I/O stalls occur since
io_submit(2) calls are skipped while plugged.
Reported-by: Nikolay Tenev <nt@storpool.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20220609164712.1539045-2-stefanha@redhat.com
Cc: Stefano Garzarella <sgarzare@redhat.com>
Fixes: 68d7946648 ("linux-aio: add `dev_max_batch` parameter to laio_io_unplug()")
[Stefano Garzarella suggested adding a Fixes tag.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'block/linux-aio.c')
| -rw-r--r-- | block/linux-aio.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/block/linux-aio.c b/block/linux-aio.c index 4c423fcccf..6078da7e42 100644 --- a/block/linux-aio.c +++ b/block/linux-aio.c @@ -363,8 +363,10 @@ void laio_io_unplug(BlockDriverState *bs, LinuxAioState *s, uint64_t dev_max_batch) { assert(s->io_q.plugged); + s->io_q.plugged--; + if (s->io_q.in_queue >= laio_max_batch(s, dev_max_batch) || - (--s->io_q.plugged == 0 && + (!s->io_q.plugged && !s->io_q.blocked && !QSIMPLEQ_EMPTY(&s->io_q.pending))) { ioq_submit(s); } |