From patchwork Wed Jun 1 14:51:46 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benny Halevy X-Patchwork-Id: 840482 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.3) with ESMTP id p51EppqC002237 for ; Wed, 1 Jun 2011 14:51:51 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756875Ab1FAOvu (ORCPT ); Wed, 1 Jun 2011 10:51:50 -0400 Received: from daytona.panasas.com ([67.152.220.89]:27225 "EHLO daytona.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756550Ab1FAOvt (ORCPT ); Wed, 1 Jun 2011 10:51:49 -0400 Received: from [172.17.33.84] ([172.17.33.84]) by daytona.panasas.com with Microsoft SMTPSVC(6.0.3790.4675); Wed, 1 Jun 2011 10:51:48 -0400 Message-ID: <4DE65202.2010502@panasas.com> Date: Wed, 01 Jun 2011 17:51:46 +0300 From: Benny Halevy User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110428 Fedora/3.1.10-1.fc14 Thunderbird/3.1.10 MIME-Version: 1.0 To: Weston Andros Adamson CC: Boaz Harrosh , trond@netapp.com, linux-nfs@vger.kernel.org Subject: Re: [PATCH] NFS: filelayout should use nfs_generic_pg_test References: <1306898310-9229-1-git-send-email-dros@netapp.com> <4DE5D287.603@panasas.com> <09816808-BA7B-4EAF-A18A-866B5A98BF25@netapp.com> In-Reply-To: <09816808-BA7B-4EAF-A18A-866B5A98BF25@netapp.com> X-OriginalArrivalTime: 01 Jun 2011 14:51:49.0013 (UTC) FILETIME=[6F706C50:01CC206B] Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Wed, 01 Jun 2011 14:51:51 +0000 (UTC) On 2011-06-01 17:44, Weston Andros Adamson wrote: > > On Jun 1, 2011, at 1:47 AM, Boaz Harrosh wrote: > >> On 06/01/2011 06:18 AM, Weston Andros Adamson wrote: >>> Use nfs_generic_pg_test instead of pnfs_generic_pg_test. >>> >>> This fixes the BUG at fs/nfs/write.c:941 introduced by >>> 89a58e32d9105c01022a757fb32ddc3b51bf0025. >>> >>> I was able to trigger this BUG reliably using pynfs in pnfs mode, >>> by using dd(1) to write many small blocks. >>> >>> Signed-off-by: Weston Andros Adamson >>> --- >>> Fix proposed by Trond. >>> >>> Benny- Does this make sense? >>> >>> fs/nfs/nfs4filelayout.c | 2 +- >>> fs/nfs/pagelist.c | 5 ++++- >>> include/linux/nfs_page.h | 3 ++- >>> 3 files changed, 7 insertions(+), 3 deletions(-) >>> >>> diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c >>> index 4269088..1c3bb72 100644 >>> --- a/fs/nfs/nfs4filelayout.c >>> +++ b/fs/nfs/nfs4filelayout.c >>> @@ -661,7 +661,7 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, >>> u64 p_stripe, r_stripe; >>> u32 stripe_unit; >>> >>> - if (!pnfs_generic_pg_test(pgio, prev, req)) >>> + if (!nfs_generic_pg_test(pgio, prev, req)) >>> return 0; >>> >> >> pnfs_generic_pg_test is the one that gets the layout. >> >> What you've done is revert to MDS IO >> >> Boaz > > Ah, you're right - I didn't even notice that! I usually confirm client -> DS communication with tcpdump. I was working for too long yesterday :) > > Patch: recalled. Discussion about a real fix: started. > > -dros I think the following should work: Benny git diff --stat -p -M fs/nfs/nfs4filelayout.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-) --- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c index 4269088..9f1d445 100644 --- a/fs/nfs/nfs4filelayout.c +++ b/fs/nfs/nfs4filelayout.c @@ -661,6 +661,16 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, u64 p_stripe, r_stripe; u32 stripe_unit; + /* + * FIXME: ideally we should be able to coalesce all requests + * that are not block boundary aligned, but currently this + * is problematic for the case of bsize < PAGE_CACHE_SIZE, + * since nfs_flush_multi and nfs_pagein_multi assume you + * can have only one struct nfs_page. + */ + if (desc->pg_bsize < PAGE_SIZE) + return 0; + if (!pnfs_generic_pg_test(pgio, prev, req)) return 0;