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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 454AEC433EF for ; Thu, 16 Jun 2022 13:08:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376778AbiFPNIQ (ORCPT ); Thu, 16 Jun 2022 09:08:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376425AbiFPNIP (ORCPT ); Thu, 16 Jun 2022 09:08:15 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F6B622B3B for ; Thu, 16 Jun 2022 06:08:14 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3EC8AB823C1 for ; Thu, 16 Jun 2022 13:08:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5CF82C34114; Thu, 16 Jun 2022 13:08:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655384891; bh=beLX0ltzh8b3iPH90BsYAektMpYtJisBfiiVlz3CUHg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=P0GirvugPU0SE08sitD3RV+QVUdNvGaNhYTjes49RTLGIbmgJHhufJSQ2tOfCl6Tv njwf4gzd/kyXxBJ3uh+EfVD4S4jTx7BVo/v/OJ/eUoSa9bF9ebl0vRbDoAqoiULjzt JeL9E1q87qTWT1CY27RelEvH9aUpoBIs8P48lZK8= Date: Thu, 16 Jun 2022 15:08:02 +0200 From: Greg KH To: Leah Rumancik Cc: stable@vger.kernel.org, Trond Myklebust , Chuck Lever Subject: Re: [PATCH 5.10] nfsd: Replace use of rwsem with errseq_t Message-ID: References: <20220607201036.4018806-1-lrumancik@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Jun 13, 2022 at 04:46:47PM -0700, Leah Rumancik wrote: > On Mon, Jun 13, 2022 at 09:58:21AM +0200, Greg KH wrote: > > On Tue, Jun 07, 2022 at 01:10:36PM -0700, Leah Rumancik wrote: > > > From: Trond Myklebust > > > > > > [ Upstream commit 555dbf1a9aac6d3150c8b52fa35f768a692f4eeb ] > > > > > > The nfsd_file nf_rwsem is currently being used to separate file write > > > and commit instances to ensure that we catch errors and apply them to > > > the correct write/commit. > > > We can improve scalability at the expense of a little accuracy (some > > > extra false positives) by replacing the nf_rwsem with more careful > > > use of the errseq_t mechanism to track errors across the different > > > operations. > > > > > > [Leah: This patch is for 5.10. 5011af4c698a ("nfsd: Fix stable writes") > > > introduced a 75% performance regression on parallel random write > > > workloads. With this commit, the performance is restored to 90% of what > > > it was prior to 5011af4c698a. The changes to the fsync for asynchronous > > > copies were not included in this backport version as the fsync was not > > > added until 5.14 (eac0b17a77fb).] > > > > > > Signed-off-by: Trond Myklebust > > > Signed-off-by: Chuck Lever > > > Signed-off-by: Leah Rumancik > > > [ cel: rebased on zero-verifier fix ] > > > --- > > > fs/nfsd/filecache.c | 1 - > > > fs/nfsd/filecache.h | 1 - > > > fs/nfsd/nfs4proc.c | 7 ++++--- > > > fs/nfsd/vfs.c | 40 +++++++++++++++------------------------- > > > 4 files changed, 19 insertions(+), 30 deletions(-) > > > > What about 5.15? We can't take this patch for 5.10 only as if you > > upgrade to 5.15 you would have a regression. Can you provide a version > > for that tree so that I can then apply this one too? > > > > thanks, > > > > greg k-h > > Just sent the 5.15 version. The upstream commit > (555dbf1a9aac6d3150c8b52fa35f768a692f4eeb) actually applies cleanly on > 5.15 so you can pull that or the version I just sent with the > justification for backporting. After applying this commit to 5.15, I > confirmed there was no peformance regression. Now all queued up, thanks. greg k-h