From patchwork Wed Sep 16 15:37:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Wilck X-Patchwork-Id: 11779947 X-Patchwork-Delegate: christophe.varoqui@free.fr Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C19A41580 for ; Wed, 16 Sep 2020 15:40:29 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 40DDA22288 for ; Wed, 16 Sep 2020 15:40:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 40DDA22288 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-356-mrDWb244PcqF-qVI8-fOPw-1; Wed, 16 Sep 2020 11:39:54 -0400 X-MC-Unique: mrDWb244PcqF-qVI8-fOPw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 81908192C8CC; Wed, 16 Sep 2020 15:39:49 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6695178809; Wed, 16 Sep 2020 15:39:49 +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 3D13F183D030; Wed, 16 Sep 2020 15:39:49 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 08GFdWgC024201 for ; Wed, 16 Sep 2020 11:39:32 -0400 Received: by smtp.corp.redhat.com (Postfix) id 519EA202451D; Wed, 16 Sep 2020 15:39:32 +0000 (UTC) Delivered-To: dm-devel@redhat.com Received: from mimecast-mx02.redhat.com (mimecast04.extmail.prod.ext.rdu2.redhat.com [10.11.55.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4989D20244F7 for ; Wed, 16 Sep 2020 15:39:29 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A52D0101A540 for ; Wed, 16 Sep 2020 15:39:29 +0000 (UTC) Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-530-vxBJ9j-FMauFfuKsJpyyJg-1; Wed, 16 Sep 2020 11:39:26 -0400 X-MC-Unique: vxBJ9j-FMauFfuKsJpyyJg-1 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 0A434B34E; Wed, 16 Sep 2020 15:39:39 +0000 (UTC) From: mwilck@suse.com To: Christophe Varoqui , Benjamin Marzinski Date: Wed, 16 Sep 2020 17:37:04 +0200 Message-Id: <20200916153718.582-6-mwilck@suse.com> In-Reply-To: <20200916153718.582-1-mwilck@suse.com> References: <20200916153718.582-1-mwilck@suse.com> MIME-Version: 1.0 X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false; X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-MIME-Autoconverted: from quoted-printable to 8bit by lists01.pubmisc.prod.ext.phx2.redhat.com id 08GFdWgC024201 X-loop: dm-devel@redhat.com Cc: dm-devel@redhat.com, Martin Wilck Subject: [dm-devel] [PATCH 05/19] multipathd: use volatile qualifier for running_state 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: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: redhat.com From: Martin Wilck While we access running_state only under the config_lock, we sometimes do in a loop. Use the volatile qualifier to make sure compilers can't optimize away the loads. Signed-off-by: Martin Wilck --- multipathd/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/multipathd/main.c b/multipathd/main.c index 8cc9b74..451d68c 100644 --- a/multipathd/main.c +++ b/multipathd/main.c @@ -126,7 +126,7 @@ int poll_dmevents = 0; int poll_dmevents = 1; #endif /* Don't access this variable without holding config_lock */ -enum daemon_status running_state = DAEMON_INIT; +volatile enum daemon_status running_state = DAEMON_INIT; pid_t daemon_pid; pthread_mutex_t config_lock = PTHREAD_MUTEX_INITIALIZER; pthread_cond_t config_cond;