From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 635ACC48BC2 for ; Wed, 23 Jun 2021 21:38:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49AC3600D1 for ; Wed, 23 Jun 2021 21:38:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229796AbhFWVkV (ORCPT ); Wed, 23 Jun 2021 17:40:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43280 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229774AbhFWVkT (ORCPT ); Wed, 23 Jun 2021 17:40:19 -0400 Received: from fieldses.org (fieldses.org [IPv6:2600:3c00:e000:2f7::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39B59C061574 for ; Wed, 23 Jun 2021 14:38:01 -0700 (PDT) Received: by fieldses.org (Postfix, from userid 2815) id 70E5D6208; Wed, 23 Jun 2021 17:38:00 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.11.0 fieldses.org 70E5D6208 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fieldses.org; s=default; t=1624484280; bh=gXNfmG7Ugkl7yjAM+oDHcyeHYa+0APL6q/GDe+0ZT0M=; h=Date:To:Cc:Subject:References:In-Reply-To:From:From; b=Oqb7aD53yFO6zyb8NGSfhNozHf39ldQ91RVEQ8N+PCJAg+k3nqZQvTcYtEoynAwGh 7UWnJ5FDtYy+swhp0T6OVrjh1oNFLR0RmVfONwe9sJSmQQ2X0yRG8vyeFgrnuB7+6M 6olmhKz2C8i/mmmLQprT8F2HEBdw10PhukqzcWVA= Date: Wed, 23 Jun 2021 17:38:00 -0400 To: trondmy@kernel.org Cc: Chuck Lever , "J. Bruce Fields" , linux-nfs@vger.kernel.org Subject: Re: [PATCH] nfsd: Reduce contention for the nfsd_file nf_rwsem Message-ID: <20210623213800.GG20232@fieldses.org> References: <20210617232652.264884-1-trondmy@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210617232652.264884-1-trondmy@kernel.org> User-Agent: Mutt/1.5.21 (2010-09-15) From: bfields@fieldses.org (J. Bruce Fields) Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Applying, with Chuck's Tested-by, thanks.--b. On Thu, Jun 17, 2021 at 07:26:52PM -0400, trondmy@kernel.org wrote: > From: Trond Myklebust > > When flushing out the unstable file writes as part of a COMMIT call, try > to perform most of of the data writes and waits outside the semaphore. > > This means that if the client is sending the COMMIT as part of a memory > reclaim operation, then it can continue performing I/O, with contention > for the lock occurring only once the data sync is finished. > > Fixes: 5011af4c698a ("nfsd: Fix stable writes") > Signed-off-by: Trond Myklebust > --- > fs/nfsd/vfs.c | 18 ++++++++++++++++-- > 1 file changed, 16 insertions(+), 2 deletions(-) > > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > index 15adf1f6ab21..46485c04740d 100644 > --- a/fs/nfsd/vfs.c > +++ b/fs/nfsd/vfs.c > @@ -1123,6 +1123,19 @@ nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset, > } > > #ifdef CONFIG_NFSD_V3 > +static int > +nfsd_filemap_write_and_wait_range(struct nfsd_file *nf, loff_t offset, > + loff_t end) > +{ > + struct address_space *mapping = nf->nf_file->f_mapping; > + int ret = filemap_fdatawrite_range(mapping, offset, end); > + > + if (ret) > + return ret; > + filemap_fdatawait_range_keep_errors(mapping, offset, end); > + return 0; > +} > + > /* > * Commit all pending writes to stable storage. > * > @@ -1153,10 +1166,11 @@ nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp, > if (err) > goto out; > if (EX_ISSYNC(fhp->fh_export)) { > - int err2; > + int err2 = nfsd_filemap_write_and_wait_range(nf, offset, end); > > down_write(&nf->nf_rwsem); > - err2 = vfs_fsync_range(nf->nf_file, offset, end, 0); > + if (!err2) > + err2 = vfs_fsync_range(nf->nf_file, offset, end, 0); > switch (err2) { > case 0: > nfsd_copy_boot_verifier(verf, net_generic(nf->nf_net, > -- > 2.31.1