From mboxrd@z Thu Jan 1 00:00:00 1970 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 us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D9149C433FE for ; Fri, 11 Mar 2022 02:02:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646964144; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=h1/H5hRzE7MEGzjQt2y6l82jDGaDrtDAqFuy8HODL5k=; b=bIcAci2DGHZIugslyqG2pU0Ie6HUuAVBcRc8gSAxCLiwuoR7Kog1rQNNWSHT8iZCttVsWq JS8D4CicE3ii4cWGTdH8E2JgQjF6mkXdIEogJunzao/Rw9+hHrBwF8mxpbrS2abKaVz6xN sDX4/G+QBs2uNZDE9OD7eDZAM1qZN98= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-262-d9jvf7Y7Psaz0xbrYDPaJA-1; Thu, 10 Mar 2022 21:02:21 -0500 X-MC-Unique: d9jvf7Y7Psaz0xbrYDPaJA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6A991101AA5B; Fri, 11 Mar 2022 02:02:19 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com [10.30.29.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id 451FC463ED8; Fri, 11 Mar 2022 02:02:18 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (localhost [IPv6:::1]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id 857341971665; Fri, 11 Mar 2022 02:02:16 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id 5279119641B9 for ; Fri, 11 Mar 2022 02:02:15 +0000 (UTC) Received: by smtp.corp.redhat.com (Postfix) id 14ADF1897D; Fri, 11 Mar 2022 02:02:15 +0000 (UTC) Received: from octiron.msp.redhat.com (unknown [10.15.80.209]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F3981183CA; Fri, 11 Mar 2022 02:02:14 +0000 (UTC) Received: from octiron.msp.redhat.com (localhost.localdomain [127.0.0.1]) by octiron.msp.redhat.com (8.14.9/8.14.9) with ESMTP id 22B22DsI021846; Thu, 10 Mar 2022 20:02:13 -0600 Received: (from bmarzins@localhost) by octiron.msp.redhat.com (8.14.9/8.14.9/Submit) id 22B22DIF021845; Thu, 10 Mar 2022 20:02:13 -0600 From: Benjamin Marzinski To: Christophe Varoqui Date: Thu, 10 Mar 2022 20:02:10 -0600 Message-Id: <1646964130-21800-3-git-send-email-bmarzins@redhat.com> In-Reply-To: <1646964130-21800-1-git-send-email-bmarzins@redhat.com> References: <1646964130-21800-1-git-send-email-bmarzins@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Subject: [dm-devel] [PATCH 2/2] multipathd: don't keep looping when config is delayed X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: device-mapper development , Guozhonghua , Martin Wilck MIME-Version: 1.0 Errors-To: dm-devel-bounces@redhat.com Sender: "dm-devel" X-Scanned-By: MIMEDefang 2.85 on 10.11.54.10 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit If a reconfigure is delayed because multipathd is waiting on a change uevent for a new multipath device, the main thread will not pause, but will keep looping and rechecking to see if it can reconfigure. To solve this, when __post_config_state(DAEMON_IDLE) is called, if __delayed_reconfig is set we really do want to switch to the DAEMON_IDLE state, even if there is a pending reconfigure, since it's being delayed. When the last change uevent for a new map arrives (or we time out waiting for it), a reconfigure will get triggered. However, we need to avoid a race where the main thread calls enable_delayed_reconfig() and sets __delayed_reconfig, and then the uevent thread processes a change uevent that sets the state to DAEMON_CONFIGURE, an then the main thread calls post_config_state(). In this case, multipathd would move to DAEMON_IDLE, even though the reconfigure should no longer be delayed. To avoid this, when schedule_reconfigure() is called and the daemon is currently in DAEMON_CONFIGURE or DAEMON_RUNNING, __delayed_reconfig should be cleared, so switching to DAEMON_IDLE will instead become DAEMON_CONFIGURE. Signed-off-by: Benjamin Marzinski --- multipathd/main.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/multipathd/main.c b/multipathd/main.c index 86b1745a..9bd1f530 100644 --- a/multipathd/main.c +++ b/multipathd/main.c @@ -309,6 +309,7 @@ static void __post_config_state(enum daemon_status state) * again and start another reconfigure cycle. */ if (reconfigure_pending != FORCE_RELOAD_NONE && + !__delayed_reconfig && state == DAEMON_IDLE && (old_state == DAEMON_CONFIGURE || old_state == DAEMON_RUNNING)) { @@ -353,6 +354,7 @@ void schedule_reconfigure(enum force_reload_types requested_type) break; case DAEMON_CONFIGURE: case DAEMON_RUNNING: + __delayed_reconfig = false; reconfigure_pending = type; break; default: -- 2.17.2 -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel