From mboxrd@z Thu Jan 1 00:00:00 1970 From: Al Viro Subject: Re: [patch 1/2] fs: mnt_want_write speedup Date: Thu, 2 Apr 2009 19:48:44 +0100 Message-ID: <20090402184844.GA2080@ZenIV.linux.org.uk> References: <20090310143718.GB15977@wotan.suse.de> <1236809477.30142.83.camel@nimitz> <20090312041334.GB1893@wotan.suse.de> <1237403623.8286.196.camel@nimitz> <20090402182210.GB17175@wotan.suse.de> <20090402184305.GI28946@ZenIV.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Dave Hansen , Linux Kernel Mailing List , linux-fsdevel@vger.kernel.org, Andrew Morton To: Nick Piggin Return-path: Received: from zeniv.linux.org.uk ([195.92.253.2]:42405 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751291AbZDBSsr (ORCPT ); Thu, 2 Apr 2009 14:48:47 -0400 Content-Disposition: inline In-Reply-To: <20090402184305.GI28946@ZenIV.linux.org.uk> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Thu, Apr 02, 2009 at 07:43:05PM +0100, Al Viro wrote: > FWIW, I'm not sure that this optimization is valid. We might eventually > want to go for "don't allow any new writers, remount r/o when existing > ones expire" functionality, so nested mnt_want_write() might eventually > be allowed to fail. BTW, I think that 1/2 as of Mar 10 is worth merging. There's an interesting question, though - do we want mnt_writers int or long? On 64bit boxen it can get serious...