Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753222AbYKDFYn (ORCPT ); Tue, 4 Nov 2008 00:24:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751141AbYKDFYc (ORCPT ); Tue, 4 Nov 2008 00:24:32 -0500 Received: from sca-es-mail-1.Sun.COM ([192.18.43.132]:59580 "EHLO sca-es-mail-1.sun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751102AbYKDFYb (ORCPT ); Tue, 4 Nov 2008 00:24:31 -0500 Date: Mon, 03 Nov 2008 22:24:28 -0700 From: Andreas Dilger Subject: Re: [PATCH] improve jbd fsync batching In-reply-to: <20081103122729.60582692.akpm@linux-foundation.org> To: Andrew Morton Cc: Josef Bacik , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, rwheeler@redhat.com Message-id: <20081104052428.GP3184@webber.adilger.int> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7BIT Content-disposition: inline X-GPG-Key: 1024D/0D35BED6 X-GPG-Fingerprint: 7A37 5D79 BF1B CECA D44F 8A29 A488 39F5 0D35 BED6 References: <20081028201614.GA21600@unused.rdu.redhat.com> <20081103122729.60582692.akpm@linux-foundation.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 936 Lines: 27 On Nov 03, 2008 12:27 -0800, Andrew Morton wrote: > On Tue, 28 Oct 2008 16:16:15 -0400 > Josef Bacik wrote: > > + spin_lock(&journal->j_state_lock); > > + commit_time = journal->j_average_commit_time; > > + spin_unlock(&journal->j_state_lock); > > OK, the lock is needed on 32-bit machines, I guess. Should we pessimize the 64-bit performance in that case, for 32-bit increasingly rare 32-bit platforms? It might be useful to have a spin_{,un}lock_64bit_word() helper that evaluates to a no-op on plaforms that don't need a hammer to do an atomic 64-bit update. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- 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/