From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Mason Subject: Re: [RFC PATCH 0/2] O_DIRECT locking rework Date: Tue, 24 Oct 2006 16:50:24 -0400 Message-ID: <20061024205024.GJ12815@think.oraclecorp.com> References: <20061020183237.GA8674@think.oraclecorp.com> <20061024193435.GE12815@think.oraclecorp.com> <1161721711.18096.33.camel@dyn9047017100.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel , akpm@osdl.org, Zach Brown Return-path: Received: from agminet01.oracle.com ([141.146.126.228]:38646 "EHLO agminet01.oracle.com") by vger.kernel.org with ESMTP id S965188AbWJXUui (ORCPT ); Tue, 24 Oct 2006 16:50:38 -0400 To: Badari Pulavarty Content-Disposition: inline In-Reply-To: <1161721711.18096.33.camel@dyn9047017100.beaverton.ibm.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Tue, Oct 24, 2006 at 01:28:31PM -0700, Badari Pulavarty wrote: > On Tue, 2006-10-24 at 15:34 -0400, Chris Mason wrote: > > Hello, > > > > Here is a new cut of my O_DIRECT locking rework. It has a much lower > > cpu cost than the last set, and simple benchmarks no longer show a > > regression here in system time. But, the complexity for inserting > > placeholder pages has gone up. > > > > I've also changed the way I test for a place holder page (from > > mm/filemap.c): > > > > static struct address_space placeholder_address_space; > > #define PagePlaceHolder(page) ((page)->mapping == &placeholder_address_space) > > > > This is more stable than the last one but I'm just starting to run race > > and load testing on it. > > > > -chris > > Gave it a spin with simple fsx tests and ran into .. Thanks, I missed an i_mutex change. Let me audit mutexes coming in and out again and resend. I think the new rules should be: reads: don't need i_mutex at all writes: don't need i_mutex for io inside i_size. Oh, and don't mess with i_mutex under DIO_OWN_LOCKING. -chris