From aad653a0bc09dd4ebcb5579f9f835bbae9ef2ba3 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 19 May 2015 15:58:37 +1000 Subject: block: discard bdi_unregister() in favour of bdi_destroy() bdi_unregister() now contains very little functionality. It contains a "WARN_ON" if bdi->dev is NULL. This warning is of no real consequence as bdi->dev isn't needed by anything else in the function, and it triggers if blk_cleanup_queue() -> bdi_destroy() is called before bdi_unregister, which happens since Commit: 6cd18e711dd8 ("block: destroy bdi before blockdev is unregistered.") So this isn't wanted. It also calls bdi_set_min_ratio(). This needs to be called after writes through the bdi have all been flushed, and before the bdi is destroyed. Calling it early is better than calling it late as it frees up a global resource. Calling it immediately after bdi_wb_shutdown() in bdi_destroy() perfectly fits these requirements. So bdi_unregister() can be discarded with the important content moved to bdi_destroy(), as can the writeback_bdi_unregister event which is already not used. Reported-by: Mike Snitzer Cc: stable@vger.kernel.org (v4.0) Fixes: c4db59d31e39 ("fs: don't reassign dirty inodes to default_backing_dev_info") Fixes: 6cd18e711dd8 ("block: destroy bdi before blockdev is unregistered.") Acked-by: Peter Zijlstra (Intel) Acked-by: Dan Williams Tested-by: Nicholas Moulin Signed-off-by: NeilBrown Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- include/trace/events/writeback.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/trace') diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index 880dd7437172..c178d13d6f4c 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -250,7 +250,6 @@ DEFINE_EVENT(writeback_class, name, \ DEFINE_WRITEBACK_EVENT(writeback_nowork); DEFINE_WRITEBACK_EVENT(writeback_wake_background); DEFINE_WRITEBACK_EVENT(writeback_bdi_register); -DEFINE_WRITEBACK_EVENT(writeback_bdi_unregister); DECLARE_EVENT_CLASS(wbc_class, TP_PROTO(struct writeback_control *wbc, struct backing_dev_info *bdi), -- cgit v1.2.3