From patchwork Thu Jun 18 18:32:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Giuliano Procida X-Patchwork-Id: 224290 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=-17.4 required=3.0 tests=DKIMWL_WL_MED, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 C2AE9C433E1 for ; Thu, 18 Jun 2020 18:32:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 949D7208C3 for ; Thu, 18 Jun 2020 18:32:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="PBz173l4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727045AbgFRSca (ORCPT ); Thu, 18 Jun 2020 14:32:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36294 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728230AbgFRSc3 (ORCPT ); Thu, 18 Jun 2020 14:32:29 -0400 Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D544CC06174E for ; Thu, 18 Jun 2020 11:32:28 -0700 (PDT) Received: by mail-qt1-x84a.google.com with SMTP id c22so5089069qtp.9 for ; Thu, 18 Jun 2020 11:32:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=eiPLzsJk0g1+SlwOarSq4GnaDiP7oCbmgH1CbyTDn/4=; b=PBz173l44hYE4jJcQEWieXWLdH9Di2KtnTlMO3XyAC1nuSfwhRmj8cdE/jc7DVoeoy b/eX4d4RmUAD8KoprvWTJuwdSu4TgIYQK7rdnIUEpqUgmfkSK/bbPCHQLFn4b4685xZL sInAfcIVbaQb3wLWmzv5AJYyIznAn8smVzKJFUlWroaDLnfXQTUOZHLL7RXNqrR7UpA1 gZPlNh2H+IW3BkOEckvQgt1ZQSHRn7d6+fYDHPD3g+04+8JFZCGm5nKO/SbC1n4AYD29 VgkENR/0B91c9vmxeZuJpvqE6ZjomaSBmvs+g4oeHTjy3cgSkzqZ5ire1DzEXIWCJoAG YwFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=eiPLzsJk0g1+SlwOarSq4GnaDiP7oCbmgH1CbyTDn/4=; b=ahx3E3nF8Azj/cCnTbeyYWC8cP7ofHt3/+YUtKV9hWnWi2dM3stoom3Ws4Ijn8CxB6 mdMnv4+MdInfufAlTLL8ByLcBX/cZEsoXFa3mjntefqPqj8wySeC8+916BuYqw9cYRhG TIqEipGOz23nZttTdF268H1r1zpul8Bb85IYAkGuhTnnDjMgXXFATnRDnI6zw4Vl86BP LKwsX2/4lRaos1NsQZNWb6Os+HYfncJt7FLS2o/PcuMNLOXS57PffsfynJV1etUqxUDw 6mbyBt71xSHI0sonVmVEJqQRLJv4EK8rUfzAllP8OiDZNRFGEjCdwhlrDvZ1JlNICJZa /n4g== X-Gm-Message-State: AOAM533+yf6gcVwPtYNmomlklC73Bx49rUR3fUOqhrh3ToECiKsvJA50 AmGp4TKq6014MsM0vugi2PMYNFBHS+RHyg== X-Google-Smtp-Source: ABdhPJyGVBXBbAGCOpXv2MTM1esjGojZsIDr6KfhSou/o3fkAMYHiZWWuEfEy2ezwILUgmR29K7uIyUOunukzQ== X-Received: by 2002:a05:6214:a0e:: with SMTP id dw14mr4965912qvb.109.1592505148043; Thu, 18 Jun 2020 11:32:28 -0700 (PDT) Date: Thu, 18 Jun 2020 19:32:23 +0100 Message-Id: <20200618183223.213179-1-gprocida@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.27.0.290.gba653c62da-goog Subject: [PATCH] blk-mq: move _blk_mq_update_nr_hw_queues synchronize_rcu call From: Giuliano Procida To: gregkh@linuxfoundation.org Cc: stable@vger.kernel.org, axboe@kernel.dk, Giuliano Procida Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This fixes the 4.14 backport commit 574eb136ec7f315c3ef2ca68fa9b3e16c56baa24 which was upstream commit f5bbbbe4d63577026f908a809f22f5fd5a90ea1f. The upstream commit added a call to synchronize_rcu to _blk_mq_update_nr_hw_queues, just after freezing queues. In the backport this landed just after unfreezeing queues. This commit moves the call to its intended place. Fixes: 574eb136ec7f ("blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter") Signed-off-by: Giuliano Procida --- block/blk-mq.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 9d53f476c517..cf56bdad2e06 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2738,6 +2738,10 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, list_for_each_entry(q, &set->tag_list, tag_set_list) blk_mq_freeze_queue(q); + /* + * Sync with blk_mq_queue_tag_busy_iter. + */ + synchronize_rcu(); set->nr_hw_queues = nr_hw_queues; blk_mq_update_queue_map(set); @@ -2748,10 +2752,6 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, list_for_each_entry(q, &set->tag_list, tag_set_list) blk_mq_unfreeze_queue(q); - /* - * Sync with blk_mq_queue_tag_busy_iter. - */ - synchronize_rcu(); } void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues)