From patchwork Sat Dec 2 00:03:53 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heinz Mauelshagen X-Patchwork-Id: 10088329 X-Patchwork-Delegate: snitzer@redhat.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5740660327 for ; Sat, 2 Dec 2017 00:04:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 479DC2A0BA for ; Sat, 2 Dec 2017 00:04:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3BD232A893; Sat, 2 Dec 2017 00:04:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C79162A0BA for ; Sat, 2 Dec 2017 00:04:32 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 28324883CA; Sat, 2 Dec 2017 00:04:32 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0B5BE5D960; Sat, 2 Dec 2017 00:04:32 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id D93D74BB79; Sat, 2 Dec 2017 00:04:31 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id vB204FX7015177 for ; Fri, 1 Dec 2017 19:04:15 -0500 Received: by smtp.corp.redhat.com (Postfix) id 17C795C552; Sat, 2 Dec 2017 00:04:15 +0000 (UTC) Delivered-To: dm-devel@redhat.com Received: from redhat.com.com (unknown [10.40.205.187]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5088D5C544; Sat, 2 Dec 2017 00:04:14 +0000 (UTC) From: Heinz Mauelshagen To: dm-devel@redhat.com Date: Sat, 2 Dec 2017 01:03:53 +0100 Message-Id: <5a67d128834ffb2136e185a04a169ae52facc491.1512171097.git.heinzm@redhat.com> In-Reply-To: References: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-loop: dm-devel@redhat.com Cc: snitzer@redhat.com Subject: [dm-devel] [PATCH V2 06/12] dm raid: close MD recovery flags race window X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Sat, 02 Dec 2017 00:04:32 +0000 (UTC) X-Virus-Scanned: ClamAV using ClamSMTP The MD sync thread updates recovery flags providing state of any running,idle,frozen,recovering,reshaping,... activity it performs and updates respective flags asynchronously to dm processing raid_status(). To close that race window, take a copy of the flags and pass it into its callees. --- drivers/md/dm-raid.c | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index e37ee5f8ed3d..2d45c04f9c48 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3282,25 +3282,26 @@ static int raid_map(struct dm_target *ti, struct bio *bio) } /* Return string describing the current sync action of @mddev */ -static const char *decipher_sync_action(struct mddev *mddev) +static const char *decipher_sync_action(struct mddev *mddev, unsigned long recovery) { - if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) + if (test_bit(MD_RECOVERY_FROZEN, &recovery)) return "frozen"; - if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || - (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) { - if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) + if (!test_bit(MD_RECOVERY_DONE, &recovery) && + (test_bit(MD_RECOVERY_RUNNING, &recovery) || + (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) { + if (test_bit(MD_RECOVERY_RESHAPE, &recovery)) return "reshape"; - if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { - if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) + if (test_bit(MD_RECOVERY_SYNC, &recovery)) { + if (!test_bit(MD_RECOVERY_REQUESTED, &recovery)) return "resync"; - else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) + else if (test_bit(MD_RECOVERY_CHECK, &recovery)) return "check"; return "repair"; } - if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) + if (test_bit(MD_RECOVERY_RECOVER, &recovery)) return "recover"; } @@ -3332,7 +3333,7 @@ static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev, } /* Helper to return resync/reshape progress for @rs and @array_in_sync */ -static sector_t rs_get_progress(struct raid_set *rs, +static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery, sector_t resync_max_sectors, bool *array_in_sync) { sector_t r, curr_resync_completed; @@ -3349,7 +3350,7 @@ static sector_t rs_get_progress(struct raid_set *rs, r = mddev->reshape_position; /* Reshape is relative to the array size */ - if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) || + if (test_bit(MD_RECOVERY_RESHAPE, &recovery) || r != MaxSector) { if (r == MaxSector) { *array_in_sync = true; @@ -3364,20 +3365,20 @@ static sector_t rs_get_progress(struct raid_set *rs, } /* Sync is relative to the component device size */ - } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) + } else if (test_bit(MD_RECOVERY_RUNNING, &recovery)) r = curr_resync_completed; else r = mddev->recovery_cp; if ((r == MaxSector) || - (test_bit(MD_RECOVERY_DONE, &mddev->recovery) && + (test_bit(MD_RECOVERY_DONE, &recovery) && (mddev->curr_resync_completed == resync_max_sectors))) { /* * Sync complete. */ *array_in_sync = true; r = resync_max_sectors; - } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { + } else if (test_bit(MD_RECOVERY_REQUESTED, &recovery)) { /* * If "check" or "repair" is occurring, the raid set has * undergone an initial sync and the health characters @@ -3420,6 +3421,7 @@ static void raid_status(struct dm_target *ti, status_type_t type, struct r5conf *conf = mddev->private; int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0; bool array_in_sync; + unsigned long recovery; unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */ unsigned int sz = 0; unsigned int rebuild_disks; @@ -3439,13 +3441,14 @@ static void raid_status(struct dm_target *ti, status_type_t type, /* Access most recent mddev properties for status output */ smp_rmb(); + recovery = rs->md.recovery; /* Get sensible max sectors even if raid set not yet started */ resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ? mddev->resync_max_sectors : mddev->dev_sectors; - progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync); + progress = rs_get_progress(rs, recovery, resync_max_sectors, &array_in_sync); resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ? atomic64_read(&mddev->resync_mismatches) : 0; - sync_action = decipher_sync_action(&rs->md); + sync_action = decipher_sync_action(&rs->md, recovery); /* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */ for (i = 0; i < rs->raid_disks; i++)