Return-Path: Received: from daytona.panasas.com ([67.152.220.89]:57349 "EHLO daytona.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758654Ab1E0HWy (ORCPT ); Fri, 27 May 2011 03:22:54 -0400 Message-ID: <4DDF5150.6010600@panasas.com> Date: Fri, 27 May 2011 10:22:56 +0300 From: Boaz Harrosh To: Trond Myklebust CC: Benny Halevy , linux-nfs@vger.kernel.org Subject: Re: Subject: [PATCH] SQUASHME: Move a check from nfs_pageio_do_add_request to nfs_generic_pg_test References: <4DDD7392.6040505@panasas.com> <1306359021-17987-1-git-send-email-bhalevy@panasas.com> <4DDEA75E.2090709@panasas.com> <4DDEB0DF.70409@panasas.com> <1306440689.31601.7.camel@lade.trondhjem.org> In-Reply-To: <1306440689.31601.7.camel@lade.trondhjem.org> Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On 05/26/2011 11:11 PM, Trond Myklebust wrote: > On Thu, 2011-05-26 at 22:58 +0300, Boaz Harrosh wrote: >> On 05/26/2011 10:17 PM, Boaz Harrosh wrote: >>> >>> desc->pg_bsize is negotiated with the MDS. But if we are doing >>> pnfs-IO it is not relevant. >>> >>> While at it cleanup nfs_pageio_do_add_request() in light of the >>> less things it needs to do. >>> >>> Signed-off-by: Boaz Harrosh >>> --- >>> fs/nfs/pagelist.c | 28 ++++++++++++++-------------- >>> 1 files changed, 14 insertions(+), 14 deletions(-) >>> >>> diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c >>> index c795660..130b683 100644 >>> --- a/fs/nfs/pagelist.c >>> +++ b/fs/nfs/pagelist.c >>> @@ -206,6 +206,16 @@ nfs_wait_on_request(struct nfs_page *req) >>> >>> static bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *prev, struct nfs_page *req) >>> { >>> + /* >>> + * 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; >>> + >>> return desc->pg_count + req->wb_bytes <= desc->pg_bsize; >>> } >>> >>> @@ -278,29 +288,19 @@ static bool nfs_can_coalesce_requests(struct nfs_page *prev, >>> static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc, >>> struct nfs_page *req) >>> { >>> - size_t newlen = req->wb_bytes; >>> - >>> if (desc->pg_count != 0) { >>> struct nfs_page *prev; >>> >>> - /* >>> - * 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; >>> - newlen += desc->pg_count; >>> + desc->pg_count += req->wb_bytes; >> >> - desc->pg_count += req->wb_bytes; >> >>> prev = nfs_list_entry(desc->pg_list.prev); >>> if (!nfs_can_coalesce_requests(prev, req, desc)) >>> return 0; >> >> + desc->pg_count += req->wb_bytes; >> >>> - } else >>> + } else { >>> desc->pg_base = req->wb_pgbase; >>> + desc->pg_count = req->wb_bytes; >>> + } >>> nfs_list_remove_request(req); >>> nfs_list_add_request(req, &desc->pg_list); >>> - desc->pg_count = newlen; > > Wait. Why not just replace this line with > > desc->pg_count += req->wb_bytes; > > That should always be correct. > Sure, OK, since desc->pg_count should be zero. Benny could you make the change before you submit/squash. Thanks Boaz