Stanislaw Gruszka
2014-Feb-08 22:18 UTC
[PATCH] btrfs: always choose work from prio_head first
In case we do not refill, we can overwrite cur pointer from prio_head by one from not prioritized head, what looks as something that was not intended. This change make we always take works from prio_head first until it's not empty. Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl> --- I found this by reading code, not sure if change is correct. Patch is only compile tested. fs/btrfs/async-thread.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c index c1e0b0c..0b78bf2 100644 --- a/fs/btrfs/async-thread.c +++ b/fs/btrfs/async-thread.c @@ -262,18 +262,19 @@ static struct btrfs_work *get_next_work(struct btrfs_worker_thread *worker, struct btrfs_work *work = NULL; struct list_head *cur = NULL; - if (!list_empty(prio_head)) + if (!list_empty(prio_head)) { cur = prio_head->next; + goto out; + } smp_mb(); if (!list_empty(&worker->prio_pending)) goto refill; - if (!list_empty(head)) + if (!list_empty(head)) { cur = head->next; - - if (cur) goto out; + } refill: spin_lock_irq(&worker->lock); -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html