From patchwork Sat Jan 14 00:34:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Chamberlain X-Patchwork-Id: 13101757 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 E33FDC678D8 for ; Sat, 14 Jan 2023 00:34:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231340AbjANAe3 (ORCPT ); Fri, 13 Jan 2023 19:34:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231177AbjANAeZ (ORCPT ); Fri, 13 Jan 2023 19:34:25 -0500 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1CA1D88DE8; Fri, 13 Jan 2023 16:34:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=Hpr/9jQDqw/KS+tNzRfC56bSFqyP+99s0sQ8H7c0B8s=; b=2alpiXcCssfDdK52ROORFPcF3V 8YM3/lsIO4xIwH6lET7RQv5nSWXC10JTqp25CXwpLOcgh37iv4duhWMVoC6k/p7GNmip2k7Uui/NM E6IYvQLVWCSLzbhavkQAqAOcUb0lnn061EHM1bsF86swFdnpoCLBMUooJycWvyV9H0wlQw2PYapuK WCK5qBV+nkmQE1lTlcwdBrgWUDVHoBo9NzG8QkpobpQ42rpuRYebQV3IRimCzc09lJlxqslGt4Xhm XeHysnS09FFh8jJqSHdIbQV7fbGageM97bIMcXzUgaxtClqrQ+g3KrUYMsM08graJ8wrKUFXTk8js NqXe0K8w==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1pGUUt-004twP-IT; Sat, 14 Jan 2023 00:34:11 +0000 From: Luis Chamberlain To: hch@infradead.org, djwong@kernel.org, song@kernel.org, rafael@kernel.org, gregkh@linuxfoundation.org, viro@zeniv.linux.org.uk, jack@suse.cz, bvanassche@acm.org, ebiederm@xmission.com Cc: mchehab@kernel.org, keescook@chromium.org, p.raghav@samsung.com, linux-fsdevel@vger.kernel.org, kernel@tuxforce.de, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Luis Chamberlain Subject: [RFC v3 15/24] nfsd: replace kthread freezing with auto fs freezing Date: Fri, 13 Jan 2023 16:34:00 -0800 Message-Id: <20230114003409.1168311-16-mcgrof@kernel.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20230114003409.1168311-1-mcgrof@kernel.org> References: <20230114003409.1168311-1-mcgrof@kernel.org> MIME-Version: 1.0 Sender: Luis Chamberlain Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org The kernel power management now supports allowing the VFS to handle filesystem freezing freezes and thawing. Take advantage of that and remove the kthread freezing. This is needed so that we properly really stop IO in flight without races after userspace has been frozen. Without this we rely on kthread freezing and its semantics are loose and error prone. The filesystem therefore is in charge of properly dealing with quiescing of the filesystem through its callbacks if it thinks it knows better than how the VFS handles it. The following Coccinelle rule was used as to remove the now superflous freezer calls: spatch --sp-file fs-freeze-cleanup.cocci --in-place --timeout 120 --dir fs/nfs --jobs 12 --use-gitgrep @ remove_set_freezable @ expression time; statement S, S2; expression task, current; @@ ( - set_freezable(); | - if (try_to_freeze()) - continue; | - try_to_freeze(); | - freezable_schedule(); + schedule(); | - freezable_schedule_timeout(time); + schedule_timeout(time); | - if (freezing(task)) { S } | - if (freezing(task)) { S } - else { S2 } | - freezing(current) ) @ remove_wq_freezable @ expression WQ_E, WQ_ARG1, WQ_ARG2, WQ_ARG3, WQ_ARG4; identifier fs_wq_fn; @@ ( WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_FREEZABLE, + WQ_ARG2, ...); | WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_FREEZABLE | WQ_ARG3, + WQ_ARG2 | WQ_ARG3, ...); | WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_ARG3 | WQ_FREEZABLE, + WQ_ARG2 | WQ_ARG3, ...); | WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_ARG3 | WQ_FREEZABLE | WQ_ARG4, + WQ_ARG2 | WQ_ARG3 | WQ_ARG4, ...); | WQ_E = - WQ_ARG1 | WQ_FREEZABLE + WQ_ARG1 | WQ_E = - WQ_ARG1 | WQ_FREEZABLE | WQ_ARG3 + WQ_ARG1 | WQ_ARG3 | fs_wq_fn( - WQ_FREEZABLE | WQ_ARG2 | WQ_ARG3 + WQ_ARG2 | WQ_ARG3 ) | fs_wq_fn( - WQ_FREEZABLE | WQ_ARG2 + WQ_ARG2 ) | fs_wq_fn( - WQ_FREEZABLE + 0 ) ) @ add_auto_flag @ expression E1; identifier fs_type; @@ struct file_system_type fs_type = { .fs_flags = E1 + | FS_AUTOFREEZE , }; Generated-by: Coccinelle SmPL Signed-off-by: Luis Chamberlain --- fs/nfsd/nfssvc.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 1ed29eac80ed..5345c415c2bc 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -963,8 +963,6 @@ nfsd(void *vrqstp) atomic_inc(&nfsdstats.th_cnt); - set_freezable(); - /* * The main request loop */