From patchwork Fri Mar 11 02:02:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Marzinski X-Patchwork-Id: 12777260 X-Patchwork-Delegate: christophe.varoqui@free.fr 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 8D608C433F5 for ; Fri, 11 Mar 2022 02:03:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646964207; 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=RKsB+y1IVdZ7uUzveeOUdaARL/gI9Q1PSxObeSDF9gQ=; b=HgakCe9pLzQ58X8Qrx72lY39+RuzV+CX+I3oKKyAhG6XGNztGPVdvef9q3xwRF+eFgPfHf vzuec3xXyqxoa3W/XCEAXJG7Zdmdf3rEHHdqDJH4UAzHA1tLi8hSR2+bLAqD2ZKZ/EnDLa ooPb8l9+KYmjXtbBD0qb1fueRywXU6U= 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-434-jVUJMLNHN4GIDzRlK_9QBA-1; Thu, 10 Mar 2022 21:03:26 -0500 X-MC-Unique: jVUJMLNHN4GIDzRlK_9QBA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 42E0E101AA45; Fri, 11 Mar 2022 02:03:24 +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 2C08C4428F2; Fri, 11 Mar 2022 02:02:46 +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 B7F7D19679FF; Fri, 11 Mar 2022 02:02:30 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id 252E4194F4AE for ; Fri, 11 Mar 2022 02:02:29 +0000 (UTC) Received: by smtp.corp.redhat.com (Postfix) id 76A143058F; Fri, 11 Mar 2022 02:02:28 +0000 (UTC) Received: from octiron.msp.redhat.com (unknown [10.15.80.209]) by smtp.corp.redhat.com (Postfix) with ESMTPS id EFAD83058D; Fri, 11 Mar 2022 02:02:13 +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 22B22CCb021842; Thu, 10 Mar 2022 20:02:12 -0600 Received: (from bmarzins@localhost) by octiron.msp.redhat.com (8.14.9/8.14.9/Submit) id 22B22BuW021841; Thu, 10 Mar 2022 20:02:11 -0600 From: Benjamin Marzinski To: Christophe Varoqui Date: Thu, 10 Mar 2022 20:02:09 -0600 Message-Id: <1646964130-21800-2-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 2.84 on 10.5.11.23 Subject: [dm-devel] [PATCH 1/2] multipathd: set reload_type in when calling reconfigure() 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 , Martin Wilck MIME-Version: 1.0 Errors-To: dm-devel-bounces@redhat.com Sender: "dm-devel" X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 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 From: Martin Wilck Only set reload_type (and reset reconfigure_pending) immediately before we actually call reconfigure(). This allows us to get rid of the reload_type global variable, and makes sure that reconfigure() is called with the reload type that was last requested. While at it, convert configure() and reconfigure() to static functions. Signed-off-by: Martin Wilck Signed-off-by: Benjamin Marzinski --- multipathd/main.c | 34 ++++++++++++++++------------------ 1 file changed, 16 insertions(+), 18 deletions(-) diff --git a/multipathd/main.c b/multipathd/main.c index f2c0b280..86b1745a 100644 --- a/multipathd/main.c +++ b/multipathd/main.c @@ -287,14 +287,10 @@ enum daemon_status wait_for_state_change_if(enum daemon_status oldstate, /* Don't access this variable without holding config_lock */ static enum force_reload_types reconfigure_pending = FORCE_RELOAD_NONE; -/* Only set while changing to DAEMON_CONFIGURE, and only access while - * reconfiguring or scheduling a delayed reconfig in DAEMON_CONFIGURE */ -static volatile enum force_reload_types reload_type = FORCE_RELOAD_NONE; static void enable_delayed_reconfig(void) { pthread_mutex_lock(&config_lock); - reconfigure_pending = reload_type; __delayed_reconfig = true; pthread_mutex_unlock(&config_lock); } @@ -324,11 +320,6 @@ static void __post_config_state(enum daemon_status state) old_state = DAEMON_IDLE; state = DAEMON_CONFIGURE; } - if (state == DAEMON_CONFIGURE) { - reload_type = (reconfigure_pending == FORCE_RELOAD_YES) ? FORCE_RELOAD_YES : FORCE_RELOAD_WEAK; - reconfigure_pending = FORCE_RELOAD_NONE; - __delayed_reconfig = false; - } running_state = state; pthread_cond_broadcast(&config_cond); do_sd_notify(old_state, state); @@ -2714,8 +2705,8 @@ checkerloop (void *ap) return NULL; } -int -configure (struct vectors * vecs) +static int +configure (struct vectors * vecs, enum force_reload_types reload_type) { struct multipath * mpp; struct path * pp; @@ -2846,8 +2837,8 @@ void rcu_free_config(struct rcu_head *head) free_config(conf); } -int -reconfigure (struct vectors * vecs) +static int +reconfigure (struct vectors *vecs, enum force_reload_types reload_type) { struct config * old, *conf; int old_marginal_pathgroups; @@ -2894,8 +2885,7 @@ reconfigure (struct vectors * vecs) #ifdef FPIN_EVENT_HANDLER fpin_clean_marginal_dev_list(NULL); #endif - configure(vecs); - + configure(vecs, reload_type); return 0; } @@ -3406,13 +3396,21 @@ child (__attribute__((unused)) void *param) break; if (state == DAEMON_CONFIGURE) { int rc = 0; + enum force_reload_types reload_type; pthread_cleanup_push(cleanup_lock, &vecs->lock); lock(&vecs->lock); pthread_testcancel(); - if (!need_to_delay_reconfig(vecs)) - rc = reconfigure(vecs); - else + if (!need_to_delay_reconfig(vecs)) { + pthread_mutex_lock(&config_lock); + reload_type = reconfigure_pending == FORCE_RELOAD_YES ? + FORCE_RELOAD_YES : FORCE_RELOAD_WEAK; + reconfigure_pending = FORCE_RELOAD_NONE; + __delayed_reconfig = false; + pthread_mutex_unlock(&config_lock); + + rc = reconfigure(vecs, reload_type); + } else enable_delayed_reconfig(); lock_cleanup_pop(vecs->lock); if (!rc) From patchwork Fri Mar 11 02:02:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Marzinski X-Patchwork-Id: 12777259 X-Patchwork-Delegate: christophe.varoqui@free.fr 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 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: