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 27BC6C433EF for ; Mon, 13 Jun 2022 07:58:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238727AbiFMH6d (ORCPT ); Mon, 13 Jun 2022 03:58:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239477AbiFMH61 (ORCPT ); Mon, 13 Jun 2022 03:58:27 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DBC82622 for ; Mon, 13 Jun 2022 00:58:24 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 2B5D761016 for ; Mon, 13 Jun 2022 07:58:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C4FAC34114; Mon, 13 Jun 2022 07:58:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655107103; bh=c2BctJSlNeIaToxp09KtxqMpkqz13tGJlkLG924B4MA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GXMtBBLh/uXZ+7y36xigj1EgUwTEWrILOoCpgQnAlJQoTbNIlDQLXPmieuXL0cnyS 8TjGf8BqEpJP6hD0xz7wix4ZJsixv7PPnxdMvzKaVhMj+Gor5JhrcDbtab59N5dhW0 gThEdOEGQ1H1wyAycgmjr69foWvAV1Hc5gXxjHo0= Date: Mon, 13 Jun 2022 09:58:21 +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: <20220607201036.4018806-1-lrumancik@google.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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