From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from victor.provo.novell.com ([137.65.250.26]:42841 "EHLO prv3-mh.provo.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S965016AbbENTlq (ORCPT ); Thu, 14 May 2015 15:41:46 -0400 From: Filipe Manana To: linux-btrfs@vger.kernel.org Cc: ce3g8jdj@umail.furryterror.org, Filipe Manana Subject: [PATCH] Btrfs: wake up extent state waiters on unlock through clear_extent_bits Date: Thu, 14 May 2015 20:41:07 +0100 Message-Id: <1431632467-2000-1-git-send-email-fdmanana@suse.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: When we clear an extent state's EXTENT_LOCKED bit with clear_extent_bits() through free_io_failure(), we weren't waking up any tasks waiting for the extent's state EXTENT_LOCKED bit, leading to an hang. So make sure clear_extent_bits() ends up waking up any waiters if the bit EXTENT_LOCKED is supplied by its callers. Zygo Blaxell was experiencing such hangs at inode eviction time after file unlinks. Thanks to him for a set of scripts to reproduce the issue. Reported-by: Zygo Blaxell Signed-off-by: Filipe Manana --- fs/btrfs/extent_io.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index c32d226..856c2e8 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1277,7 +1277,12 @@ int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, unsigned bits, gfp_t mask) { - return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask); + int wake = 0; + + if (bits & EXTENT_LOCKED) + wake = 1; + + return clear_extent_bit(tree, start, end, bits, wake, 0, NULL, mask); } int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, -- 2.1.3