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=-15.8 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,URIBL_RED 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 D725BC4743F for ; Wed, 9 Jun 2021 00:13:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BBA2861375 for ; Wed, 9 Jun 2021 00:13:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232410AbhFIAPQ (ORCPT ); Tue, 8 Jun 2021 20:15:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:43608 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232160AbhFIAPQ (ORCPT ); Tue, 8 Jun 2021 20:15:16 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E44256135D; Wed, 9 Jun 2021 00:13:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1623197588; bh=Psrqb2pnGz7t3VvyjRn5OCpts4d5ozTvT//kSqfmbJU=; h=Date:From:To:Subject:From; b=qhbCk3Urzwhx1JIqzml9+YGsKYF+wljm3tRROivDGdTWrrmoD/jZR3HdQtpAM1CHo nPzJb+HyGSKRQAZz6pazoNxPjKgQuKg7Iw9HmhdBZk75T795KPbNzynp7on4FGGsUI n3JvhdAtwNGXK3LF0pTfd5ceEDLnFlUqT/xNTpjc= Date: Tue, 08 Jun 2021 17:13:07 -0700 From: akpm@linux-foundation.org To: axboe@kernel.dk, dchinner@redhat.com, dennis@kernel.org, guro@fb.com, jack@suse.com, jack@suse.cz, mm-commits@vger.kernel.org, tj@kernel.org, viro@zeniv.linux.org.uk Subject: + writeback-cgroup-switch-to-rcu_work-api-in-inode_switch_wbs.patch added to -mm tree Message-ID: <20210609001307.sMxnZFK4G%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: writeback, cgroup: switch to rcu_work API in inode_switch_wbs() has been added to the -mm tree. Its filename is writeback-cgroup-switch-to-rcu_work-api-in-inode_switch_wbs.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/writeback-cgroup-switch-to-rcu_work-api-in-inode_switch_wbs.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/writeback-cgroup-switch-to-rcu_work-api-in-inode_switch_wbs.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Roman Gushchin Subject: writeback, cgroup: switch to rcu_work API in inode_switch_wbs() Inode's wb switching requires two steps divided by an RCU grace period. It's currently implemented as an RCU callback inode_switch_wbs_rcu_fn(), which schedules inode_switch_wbs_work_fn() as a work. Switching to the rcu_work API allows to do the same in a cleaner and slightly shorter form. Link: https://lkml.kernel.org/r/20210608230225.2078447-5-guro@fb.com Signed-off-by: Roman Gushchin Reviewed-by: Jan Kara Acked-by: Tejun Heo Acked-by: Dennis Zhou Cc: Alexander Viro Cc: Dave Chinner Cc: Jan Kara Cc: Jens Axboe Signed-off-by: Andrew Morton --- fs/fs-writeback.c | 18 ++++-------------- 1 file changed, 4 insertions(+), 14 deletions(-) --- a/fs/fs-writeback.c~writeback-cgroup-switch-to-rcu_work-api-in-inode_switch_wbs +++ a/fs/fs-writeback.c @@ -335,8 +335,7 @@ struct inode_switch_wbs_context { struct inode *inode; struct bdi_writeback *new_wb; - struct rcu_head rcu_head; - struct work_struct work; + struct rcu_work work; }; static void bdi_down_write_wb_switch_rwsem(struct backing_dev_info *bdi) @@ -352,7 +351,7 @@ static void bdi_up_write_wb_switch_rwsem static void inode_switch_wbs_work_fn(struct work_struct *work) { struct inode_switch_wbs_context *isw = - container_of(work, struct inode_switch_wbs_context, work); + container_of(to_rcu_work(work), struct inode_switch_wbs_context, work); struct inode *inode = isw->inode; struct backing_dev_info *bdi = inode_to_bdi(inode); struct address_space *mapping = inode->i_mapping; @@ -469,16 +468,6 @@ skip_switch: atomic_dec(&isw_nr_in_flight); } -static void inode_switch_wbs_rcu_fn(struct rcu_head *rcu_head) -{ - struct inode_switch_wbs_context *isw = container_of(rcu_head, - struct inode_switch_wbs_context, rcu_head); - - /* needs to grab bh-unsafe locks, bounce to work item */ - INIT_WORK(&isw->work, inode_switch_wbs_work_fn); - queue_work(isw_wq, &isw->work); -} - /** * inode_switch_wbs - change the wb association of an inode * @inode: target inode @@ -536,7 +525,8 @@ static void inode_switch_wbs(struct inod * lock so that stat transfer can synchronize against them. * Let's continue after I_WB_SWITCH is guaranteed to be visible. */ - call_rcu(&isw->rcu_head, inode_switch_wbs_rcu_fn); + INIT_RCU_WORK(&isw->work, inode_switch_wbs_work_fn); + queue_rcu_work(isw_wq, &isw->work); return; out_free: _ Patches currently in -mm which might be from guro@fb.com are writeback-cgroup-do-not-switch-inodes-with-i_will_free-flag.patch writeback-cgroup-add-smp_mb-to-cgroup_writeback_umount.patch writeback-cgroup-increment-isw_nr_in_flight-before-grabbing-an-inode.patch writeback-cgroup-switch-to-rcu_work-api-in-inode_switch_wbs.patch writeback-cgroup-keep-list-of-inodes-attached-to-bdi_writeback.patch writeback-cgroup-split-out-the-functional-part-of-inode_switch_wbs_work_fn.patch writeback-cgroup-support-switching-multiple-inodes-at-once.patch writeback-cgroup-release-dying-cgwbs-by-switching-attached-inodes.patch