From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263577AbTJWNpF (ORCPT ); Thu, 23 Oct 2003 09:45:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263578AbTJWNpE (ORCPT ); Thu, 23 Oct 2003 09:45:04 -0400 Received: from e33.co.us.ibm.com ([32.97.110.131]:11155 "EHLO e33.co.us.ibm.com") by vger.kernel.org with ESMTP id S263577AbTJWNo7 (ORCPT ); Thu, 23 Oct 2003 09:44:59 -0400 Date: Thu, 23 Oct 2003 19:20:30 +0530 From: Suparna Bhattacharya To: Daniel McNeil Cc: Andrew Morton , "linux-aio@kvack.org" , Linux Kernel Mailing List , Badari Pulavarty Subject: Re: Patch for Retry based AIO-DIO (Was AIO and DIO testing on 2.6.0-test7-mm1) Message-ID: <20031023135030.GA11807@in.ibm.com> Reply-To: suparna@in.ibm.com References: <1066432378.2133.40.camel@ibm-c.pdx.osdl.net> <20031020142727.GA4068@in.ibm.com> <1066693673.22983.10.camel@ibm-c.pdx.osdl.net> <20031021121113.GA4282@in.ibm.com> <1066869631.1963.46.camel@ibm-c.pdx.osdl.net> <20031023104923.GA11543@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20031023104923.GA11543@in.ibm.com> User-Agent: Mutt/1.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 23, 2003 at 04:19:23PM +0530, Suparna Bhattacharya wrote: > On Wed, Oct 22, 2003 at 05:40:32PM -0700, Daniel McNeil wrote: > > Suparna and Andrew, > > > > I've been doing more testing using the test programs I wrote to > > try and hit the AIO verses buffered read race conditions. > > > > I tested 2.6.0-test8, 2.6.0-test8-mm1+(your first incomplete fix) and > > 2.6.0-test8-mm1+aio-dio-retry patch. I used my test programs > > (http://developer.osdl.org/daniel/AIO/TESTS/) by doing: > > > > Run "dirty" program which allocates and writes 0xaa to a file and then > > frees the space. > > Run "dio_sparse" or "aiodio-sparse - which creates "file", truncates it > > up to 64MB and then writes zeros into the holes (using DIO or > > AIO+DIO). At same time, a forked child is reading the file > > looking for non-zero data. > > rm "file" > > > > On 2.6.0-test8 > > ============== > > I hit the race condition and see uninitialized data: > > ~/AIO/TESTS/dio_sparse > > non zero buffer at buf[4] => 0xaaaaaaaa,aaaaaaaa,aaaaaaaa,aaaaaaaa > > non-zero read at offset 24182785 > > > > ~/AIO/TESTS/aiodio_sparse > > non zero buffer at buf[4] -> 0xaaaaaaaa,aaaaaaaa,aaaaaaaa,aaaaaaaa > > non-zero read at offset 8323062 > > > > > > On 2.6.0-test8-mm1+1st-direct-io-aio_complete patch and > > 2.6.0-test8-mm1+aio-dio-retry patch > > > > I never see uninitialized data. > > That's good news. > > You seem to be able to run test8-mm1 just fine; I have been > running into strange oops on syscall return for io_getevents :( > - haven't seen this before. > What library and header files are you using for libaio ? Do you have > 4G-4G turned on in your build ? It turns out that backing out gcc-Os.patch (on RH 9) or switching to a system with an older compiler version made those errors go away. Regards Suparna -- Suparna Bhattacharya (suparna@in.ibm.com) Linux Technology Center IBM Software Labs, India