From nobody Wed Feb 11 18:03:49 2026 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 638ADC77B75 for ; Sat, 6 May 2023 01:24:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232091AbjEFBYq (ORCPT ); Fri, 5 May 2023 21:24:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231530AbjEFBY3 (ORCPT ); Fri, 5 May 2023 21:24:29 -0400 Received: from dggsgout12.his.huawei.com (unknown [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 907D96EAF; Fri, 5 May 2023 18:24:28 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4QCqbD2gl1z4f3npy; Sat, 6 May 2023 09:24:24 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.127.227]) by APP4 (Coremail) with SMTP id gCh0CgD3X7NHrFVkfh1lIw--.56086S8; Sat, 06 May 2023 09:24:26 +0800 (CST) From: linan666@huaweicloud.com To: song@kernel.org, neilb@suse.de, Rob.Becker@riverbed.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 v2 4/4] md/raid10: optimize check_decay_read_errors() Date: Sat, 6 May 2023 09:23:15 +0800 Message-Id: <20230506012315.3370489-5-linan666@huaweicloud.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230506012315.3370489-1-linan666@huaweicloud.com> References: <20230506012315.3370489-1-linan666@huaweicloud.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgD3X7NHrFVkfh1lIw--.56086S8 X-Coremail-Antispam: 1UD129KBjvJXoWxCFWxAF4UZFWfKrWkJrW8JFb_yoWrZF4fpa n8Aas8Jr1UJryUAw1DJFyDt3WFyryfAayjyrWxJa1xXwn5Jrn8ta4UGry29348Gas8Aw15 XFZ8Grs8CF4DKFUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmFb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E 14v26rxl6s0DM2vYz4IE04k24VAvwVAKI4IrM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I 8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r106r15McIj6I8E87Iv67AK xVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxV A2Y2ka0xkIwI1lw4CEc2x0rVAKj4xxMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY 6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17 CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF 0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIx AIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2 KfnxnUUI43ZEXa7IU1nmitUUUUU== X-CM-SenderInfo: polqt0awwwqx5xdzvxpfor3voofrz/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Li Nan check_decay_read_errors() is used to handle rdev->read_errors. But read_errors is inc and read after check_decay_read_errors() is invoked in fix_read_error(). Put all operations of read_errors into check_decay_read_errors() and clean up unnecessary atomic_read of read_errors. Suggested-by: Yu Kuai Signed-off-by: Li Nan --- drivers/md/raid10.c | 66 ++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 31 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 4d615fcc6a50..79f94882227d 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -2655,39 +2655,53 @@ static void recovery_request_write(struct mddev *md= dev, struct r10bio *r10_bio) } =20 /* - * Used by fix_read_error() to decay the per rdev read_errors. + * Used by fix_read_error() to decay the per rdev read_errors and check if + * read_error > max_read_errors. * We halve the read error count for every hour that has elapsed * since the last recorded read error. * */ -static void check_decay_read_errors(struct mddev *mddev, struct md_rdev *r= dev) +static bool check_decay_read_errors(struct mddev *mddev, struct md_rdev *r= dev) { - long cur_time_mon; + time64_t cur_time_mon =3D ktime_get_seconds(); unsigned long hours_since_last; - unsigned int read_errors =3D atomic_read(&rdev->read_errors); - - cur_time_mon =3D ktime_get_seconds(); + unsigned int read_errors; + unsigned int max_read_errors =3D + atomic_read(&mddev->max_corr_read_errors); =20 if (rdev->last_read_error =3D=3D 0) { /* first time we've seen a read error */ rdev->last_read_error =3D cur_time_mon; - return; - } + } else { + hours_since_last =3D (long)(cur_time_mon - + rdev->last_read_error) / 3600; =20 - hours_since_last =3D (long)(cur_time_mon - - rdev->last_read_error) / 3600; + rdev->last_read_error =3D cur_time_mon; =20 - rdev->last_read_error =3D cur_time_mon; + /* + * if hours_since_last is > the number of bits in read_errors + * just set read errors to 0. We do this to avoid + * overflowing the shift of read_errors by hours_since_last. + */ + read_errors =3D atomic_read(&rdev->read_errors); + if (hours_since_last >=3D 8 * sizeof(read_errors)) + atomic_set(&rdev->read_errors, 0); + else + atomic_set(&rdev->read_errors, + read_errors >> hours_since_last); + } =20 - /* - * if hours_since_last is > the number of bits in read_errors - * just set read errors to 0. We do this to avoid - * overflowing the shift of read_errors by hours_since_last. - */ - if (hours_since_last >=3D 8 * sizeof(read_errors)) - atomic_set(&rdev->read_errors, 0); - else - atomic_set(&rdev->read_errors, read_errors >> hours_since_last); + read_errors =3D atomic_inc_return(&rdev->read_errors); + if (read_errors > max_read_errors) { + pr_notice("md/raid10:%s: %pg: Raid device exceeded read_error threshold = [cur %u:max %u]\n", + mdname(mddev), rdev->bdev, read_errors, max_read_errors); + pr_notice("md/raid10:%s: %pg: Failing raid device\n", + mdname(mddev), rdev->bdev); + md_error(mddev, rdev); + return false; + } + + return true; } =20 static int r10_sync_page_io(struct md_rdev *rdev, sector_t sector, @@ -2727,8 +2741,6 @@ static void fix_read_error(struct r10conf *conf, stru= ct mddev *mddev, struct r10 int sect =3D 0; /* Offset from r10_bio->sector */ int sectors =3D r10_bio->sectors; struct md_rdev *rdev; - unsigned int max_read_errors =3D - atomic_read(&mddev->max_corr_read_errors); int d =3D r10_bio->devs[r10_bio->read_slot].devnum; =20 /* still own a reference to this rdev, so it cannot @@ -2741,15 +2753,7 @@ static void fix_read_error(struct r10conf *conf, str= uct mddev *mddev, struct r10 more fix_read_error() attempts */ return; =20 - check_decay_read_errors(mddev, rdev); - atomic_inc(&rdev->read_errors); - if (atomic_read(&rdev->read_errors) > max_read_errors) { - pr_notice("md/raid10:%s: %pg: Raid device exceeded read_error threshold = [cur %u:max %u]\n", - mdname(mddev), rdev->bdev, - atomic_read(&rdev->read_errors), max_read_errors); - pr_notice("md/raid10:%s: %pg: Failing raid device\n", - mdname(mddev), rdev->bdev); - md_error(mddev, rdev); + if (check_decay_read_errors(mddev, rdev)) { r10_bio->devs[r10_bio->read_slot].bio =3D IO_BLOCKED; return; } --=20 2.31.1