From: Alex Elder Date: Tue, 9 Oct 2012 03:37:30 +0000 (-0700) Subject: rbd: reset BACKOFF if unable to re-queue X-Git-Tag: v3.7-rc4~24^2~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=588377d6199034c36d335e7df5818b731fea072c;p=pandora-kernel.git rbd: reset BACKOFF if unable to re-queue If ceph_fault() is unable to queue work after a delay, it sets the BACKOFF connection flag so con_work() will attempt to do so. In con_work(), when BACKOFF is set, if queue_delayed_work() doesn't result in newly-queued work, it simply ignores this condition and proceeds as if no backoff delay were desired. There are two problems with this--one of which is a bug. The first problem is simply that the intended behavior is to back off, and if we aren't able queue the work item to run after a delay we're not doing that. The only reason queue_delayed_work() won't queue work is if the provided work item is already queued. In the messenger, this means that con_work() is already scheduled to be run again. So if we simply set the BACKOFF flag again when this occurs, we know the next con_work() call will again attempt to hold off activity on the connection until after the delay. The second problem--the bug--is a leak of a reference count. If queue_delayed_work() returns 0 in con_work(), con->ops->put() drops the connection reference held on entry to con_work(). However, processing is (was) allowed to continue, and at the end of the function a second con->ops->put() is called. This patch fixes both problems. Signed-off-by: Alex Elder Reviewed-by: Sage Weil --- Reading git-diff-tree failed