From patchwork Wed Feb 28 11:43:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13575345 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 242BC6CDD8; Wed, 28 Feb 2024 11:49:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709120980; cv=none; b=WEttgoy4OBuBbdSECC9gdr0hzr32LhpAlpWG7oUNgW3hSqEl5ImDz7yXpnwzGnsKqNmPq14iAuXseduwWDasbfke5ZcKGMGX/PPsBfRPG+WH4Uzz/vk5FEuTFXdahhB228iYvpNPfmnMeTcD/NFA2IWXQDxeUPcbl7hKMDP8wdM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709120980; c=relaxed/simple; bh=fAkNIprYsZH5PQBVb31gePLzngvp2TZnuFAypduC6Lc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=XhIP5p4vIgDZGbrFnd25sody5QURRQm7+t+9P1mjKcM7hsvKEtpgjLS3msXoAvmDfGI1bCQP46k1bgzyjC8y0CxQdjRTgCx6KKK/clOv966f4g7bulUY8uqExajtnX8Ukg8UY10LM3Ryk0e/5ESGQzdD7899M9qhBFcPqZmPUzQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4TlCLz4MtJz4f3kKl; Wed, 28 Feb 2024 19:49:31 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id F00B91A0283; Wed, 28 Feb 2024 19:49:34 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP1 (Coremail) with SMTP id cCh0CgAn9g7IHd9l+eamFQ--.6969S11; Wed, 28 Feb 2024 19:49:34 +0800 (CST) From: Yu Kuai To: xni@redhat.com, paul.e.luse@linux.intel.com, song@kernel.org, shli@fb.com, neilb@suse.com Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH md-6.9 v3 07/11] md/raid1: factor out read_first_rdev() from read_balance() Date: Wed, 28 Feb 2024 19:43:29 +0800 Message-Id: <20240228114333.527222-8-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240228114333.527222-1-yukuai1@huaweicloud.com> References: <20240228114333.527222-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: cCh0CgAn9g7IHd9l+eamFQ--.6969S11 X-Coremail-Antispam: 1UD129KBjvJXoWxZFW8CrW5GFW3Jr1UAw13Arb_yoWrCw47pw 45AFZ3tryUXryrZws8J3yDWr93t34fJF48GrZ7Xwnagwn3KrWqgFyUGrya9Fy5Crs8Jw1U Zw15Ar4ak3Z7KFDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUP214x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E 14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIx kGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAF wI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVW8JV WxJwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsGvfC2KfnxnUUI43ZEXa7VUbmZ X7UUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai read_balance() is hard to understand because there are too many status and branches, and it's overlong. This patch factor out the case to read the first rdev from read_balance(), there are no functional changes. Co-developed-by: Paul Luse Signed-off-by: Paul Luse Signed-off-by: Yu Kuai Reviewed-by: Xiao Ni --- drivers/md/raid1.c | 63 +++++++++++++++++++++++++++++++++------------- 1 file changed, 46 insertions(+), 17 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 6e3c0d3e0b75..b42b947bbd34 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -579,6 +579,47 @@ static sector_t align_to_barrier_unit_end(sector_t start_sector, return len; } +static void update_read_sectors(struct r1conf *conf, int disk, + sector_t this_sector, int len) +{ + struct raid1_info *info = &conf->mirrors[disk]; + + atomic_inc(&info->rdev->nr_pending); + if (info->next_seq_sect != this_sector) + info->seq_start = this_sector; + info->next_seq_sect = this_sector + len; +} + +static int choose_first_rdev(struct r1conf *conf, struct r1bio *r1_bio, + int *max_sectors) +{ + sector_t this_sector = r1_bio->sector; + int len = r1_bio->sectors; + int disk; + + for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) { + struct md_rdev *rdev; + int read_len; + + if (r1_bio->bios[disk] == IO_BLOCKED) + continue; + + rdev = conf->mirrors[disk].rdev; + if (!rdev || test_bit(Faulty, &rdev->flags)) + continue; + + /* choose the first disk even if it has some bad blocks. */ + read_len = raid1_check_read_range(rdev, this_sector, &len); + if (read_len > 0) { + update_read_sectors(conf, disk, this_sector, read_len); + *max_sectors = read_len; + return disk; + } + } + + return -1; +} + /* * This routine returns the disk from which the requested read should * be done. There is a per-array 'next expected sequential IO' sector @@ -603,7 +644,6 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect sector_t best_dist; unsigned int min_pending; struct md_rdev *rdev; - int choose_first; retry: sectors = r1_bio->sectors; @@ -614,10 +654,11 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect best_pending_disk = -1; min_pending = UINT_MAX; best_good_sectors = 0; - choose_first = raid1_should_read_first(conf->mddev, this_sector, - sectors); clear_bit(R1BIO_FailFast, &r1_bio->state); + if (raid1_should_read_first(conf->mddev, this_sector, sectors)) + return choose_first_rdev(conf, r1_bio, max_sectors); + for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) { sector_t dist; sector_t first_bad; @@ -663,8 +704,6 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect * bad_sectors from another device.. */ bad_sectors -= (this_sector - first_bad); - if (choose_first && sectors > bad_sectors) - sectors = bad_sectors; if (best_good_sectors > sectors) best_good_sectors = sectors; @@ -674,8 +713,6 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect best_good_sectors = good_sectors; best_disk = disk; } - if (choose_first) - break; } continue; } else { @@ -690,10 +727,6 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect pending = atomic_read(&rdev->nr_pending); dist = abs(this_sector - conf->mirrors[disk].head_position); - if (choose_first) { - best_disk = disk; - break; - } /* Don't change to another disk for sequential reads */ if (conf->mirrors[disk].next_seq_sect == this_sector || dist == 0) { @@ -769,13 +802,9 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect rdev = conf->mirrors[best_disk].rdev; if (!rdev) goto retry; - atomic_inc(&rdev->nr_pending); - sectors = best_good_sectors; - - if (conf->mirrors[best_disk].next_seq_sect != this_sector) - conf->mirrors[best_disk].seq_start = this_sector; - conf->mirrors[best_disk].next_seq_sect = this_sector + sectors; + sectors = best_good_sectors; + update_read_sectors(conf, disk, this_sector, sectors); } *max_sectors = sectors;