From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755219Ab1FPHA0 (ORCPT ); Thu, 16 Jun 2011 03:00:26 -0400 Received: from out4.smtp.messagingengine.com ([66.111.4.28]:60440 "EHLO out4.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755001Ab1FPHAS (ORCPT ); Thu, 16 Jun 2011 03:00:18 -0400 X-Sasl-enc: wopRie0GAr9VMhe8s0H7BsKuKHvIrMJlknGc+bFw7yvK 1308207617 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Jun 15 17:02:30 2011 Message-Id: <20110616000230.176924616@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 15 Jun 2011 16:59:35 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Artem Bityutskiy Subject: [12/89] UBIFS: fix shrinker object count reports In-Reply-To: <20110616000258.GA14529@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.39-stable review patch. If anyone has any objections, please let us know. ------------------ From: Artem Bityutskiy commit cf610bf4199770420629d3bc273494bd27ad6c1d upstream. Sometimes VM asks the shrinker to return amount of objects it can shrink, and we return the ubifs_clean_zn_cnt in that case. However, it is possible that this counter is negative for a short period of time, due to the way UBIFS TNC code updates it. And I can observe the following warnings sometimes: shrink_slab: ubifs_shrinker+0x0/0x2b7 [ubifs] negative objects to delete nr=-8541616642706119788 This patch makes sure UBIFS never returns negative count of objects. Signed-off-by: Artem Bityutskiy Signed-off-by: Greg Kroah-Hartman --- fs/ubifs/shrinker.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/fs/ubifs/shrinker.c +++ b/fs/ubifs/shrinker.c @@ -283,7 +283,11 @@ int ubifs_shrinker(struct shrinker *shri long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt); if (nr == 0) - return clean_zn_cnt; + /* + * Due to the way UBIFS updates the clean znode counter it may + * temporarily be negative. + */ + return clean_zn_cnt >= 0 ? clean_zn_cnt : 1; if (!clean_zn_cnt) { /*