Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751382AbWE2V1O (ORCPT ); Mon, 29 May 2006 17:27:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751379AbWE2V1O (ORCPT ); Mon, 29 May 2006 17:27:14 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:4066 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1751380AbWE2V1M (ORCPT ); Mon, 29 May 2006 17:27:12 -0400 Date: Mon, 29 May 2006 23:27:32 +0200 From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: Arjan van de Ven , Andrew Morton Subject: [patch 55/61] lock validator: special locking: sb->s_umount Message-ID: <20060529212732.GC3155@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060529212109.GA2058@elte.hu> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -2.8 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.8 required=5.9 tests=ALL_TRUSTED,AWL autolearn=no SpamAssassin version=3.0.3 -2.8 ALL_TRUSTED Did not pass through any untrusted hosts 0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1305 Lines: 38 From: Ingo Molnar workaround for special sb->s_umount locking rule. s_umount gets held across a series of lock dropping and releasing in prune_one_dentry(), so i changed the order, at the risk of introducing a umount race. FIXME. i think a better fix would be to do the unlocks as _non_nested in prune_one_dentry(), and to do the up_read() here as an up_read_non_nested() as well? Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven --- fs/dcache.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) Index: linux/fs/dcache.c =================================================================== --- linux.orig/fs/dcache.c +++ linux/fs/dcache.c @@ -470,8 +470,9 @@ static void prune_dcache(int count, stru s_umount = &dentry->d_sb->s_umount; if (down_read_trylock(s_umount)) { if (dentry->d_sb->s_root != NULL) { - prune_one_dentry(dentry); +// lockdep hack: do this better! up_read(s_umount); + prune_one_dentry(dentry); continue; } up_read(s_umount); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/