From patchwork Wed Jun 28 01:57:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Nan X-Patchwork-Id: 13295172 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 70B38EB64D9 for ; Wed, 28 Jun 2023 01:59:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231251AbjF1B65 (ORCPT ); Tue, 27 Jun 2023 21:58:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231217AbjF1B6y (ORCPT ); Tue, 27 Jun 2023 21:58:54 -0400 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B33B2D4C; Tue, 27 Jun 2023 18:58:48 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4QrPrM5Yr2z4f3whQ; Wed, 28 Jun 2023 09:58:43 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgCH77LTk5tkJ6nJMg--.6175S6; Wed, 28 Jun 2023 09:58:45 +0800 (CST) From: linan666@huaweicloud.com To: song@kernel.org, guoqing.jiang@cloud.ionos.com, colyli@suse.de, xni@redhat.com Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, linan122@huawei.com, yukuai3@huawei.com, yi.zhang@huawei.com, houtao1@huawei.com, yangerkun@huawei.com Subject: [PATCH 2/3] md/raid10: factor out get_rdev_repl_from_mirror() Date: Wed, 28 Jun 2023 09:57:51 +0800 Message-Id: <20230628015752.102267-3-linan666@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230628015752.102267-1-linan666@huaweicloud.com> References: <20230628015752.102267-1-linan666@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgCH77LTk5tkJ6nJMg--.6175S6 X-Coremail-Antispam: 1UD129KBjvJXoW7AF1xur45Zw1rZryUtw4ktFb_yoW8CFy3pF 4DK3WfJrWUJw47KF4DXFW7Ja4avr97tFWFyryfW34ruw15trWDAF4rGrWayr98ZFZ5Zryj q3W5Kr4vk3WjgFDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUHmb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUXw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6rxl6s0DM2vYz4IE04k24VAvwVAKI4IrM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrV ACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWU JVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2 ka0xkIwI1lw4CEc2x0rVAKj4xxMxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48J MxAqzxv26xkF7I0En4kS14v26r1q6r43MxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I 8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8 ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x 0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_ Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU1 dcTDUUUUU== X-CM-SenderInfo: polqt0awwwqx5xdzvxpfor3voofrz/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org From: Li Nan Factor out a helper to get 'rdev' and 'replacement' from config->mirrors. Just to make code cleaner and prepare to fix the bug of io loss while 'replacement' replace 'rdev'. There is no functional change. Signed-off-by: Li Nan Reviewed-by: Yu Kuai --- drivers/md/raid10.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 3e6a09aaaba6..eaaf6307ddda 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1346,6 +1346,26 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio, } } +static void get_rdev_repl_from_mirror(struct raid10_info *mirror, + struct md_rdev **prdev, + struct md_rdev **prrdev) +{ + struct md_rdev *rdev, *rrdev; + + rrdev = rcu_dereference(mirror->replacement); + /* + * Read replacement first to prevent reading both rdev and + * replacement as NULL during replacement replace rdev. + */ + smp_mb(); + rdev = rcu_dereference(mirror->rdev); + if (rdev == rrdev) + rrdev = NULL; + + *prrdev = rrdev; + *prdev = rdev; +} + static void wait_blocked_dev(struct mddev *mddev, struct r10bio *r10_bio) { int i; @@ -1489,15 +1509,7 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, int d = r10_bio->devs[i].devnum; struct md_rdev *rdev, *rrdev; - rrdev = rcu_dereference(conf->mirrors[d].replacement); - /* - * Read replacement first to prevent reading both rdev and - * replacement as NULL during replacement replace rdev. - */ - smp_mb(); - rdev = rcu_dereference(conf->mirrors[d].rdev); - if (rdev == rrdev) - rrdev = NULL; + get_rdev_repl_from_mirror(&conf->mirrors[d], &rdev, &rrdev); if (rdev && (test_bit(Faulty, &rdev->flags))) rdev = NULL; if (rrdev && (test_bit(Faulty, &rrdev->flags)))