From patchwork Thu Apr 20 12:00:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 752767 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3w7yL02fCKz9s2x for ; Thu, 20 Apr 2017 22:07:36 +1000 (AEST) Received: from localhost ([::1]:53552 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d1As1-0003CJ-Gs for incoming@patchwork.ozlabs.org; Thu, 20 Apr 2017 08:07:33 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38744) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d1Amq-0007gZ-4t for qemu-devel@nongnu.org; Thu, 20 Apr 2017 08:02:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d1Ami-00034h-Pf for qemu-devel@nongnu.org; Thu, 20 Apr 2017 08:02:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54226) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d1Alo-0002Nd-B6; Thu, 20 Apr 2017 08:01:08 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DA565ADAEF; Thu, 20 Apr 2017 12:01:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com DA565ADAEF Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=pbonzini@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com DA565ADAEF Received: from donizetti.redhat.com (ovpn-117-9.ams2.redhat.com [10.36.117.9]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v3KC0w3s002037; Thu, 20 Apr 2017 08:01:05 -0400 From: Paolo Bonzini To: qemu-devel@nongnu.org Date: Thu, 20 Apr 2017 14:00:45 +0200 Message-Id: <20170420120058.28404-5-pbonzini@redhat.com> In-Reply-To: <20170420120058.28404-1-pbonzini@redhat.com> References: <20170420120058.28404-1-pbonzini@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Thu, 20 Apr 2017 12:01:07 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 04/17] block: access serialising_in_flight with atomic ops X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-block@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Signed-off-by: Paolo Bonzini Reviewed-by: Stefan Hajnoczi --- block/io.c | 6 +++--- include/block/block_int.h | 10 ++++++---- 2 files changed, 9 insertions(+), 7 deletions(-) diff --git a/block/io.c b/block/io.c index 3a27fd5..869322a 100644 --- a/block/io.c +++ b/block/io.c @@ -375,7 +375,7 @@ void bdrv_drain_all(void) static void tracked_request_end(BdrvTrackedRequest *req) { if (req->serialising) { - req->bs->serialising_in_flight--; + atomic_dec(&req->bs->serialising_in_flight); } QLIST_REMOVE(req, list); @@ -414,7 +414,7 @@ static void mark_request_serialising(BdrvTrackedRequest *req, uint64_t align) - overlap_offset; if (!req->serialising) { - req->bs->serialising_in_flight++; + atomic_inc(&req->bs->serialising_in_flight); req->serialising = true; } @@ -519,7 +519,7 @@ static bool coroutine_fn wait_serialising_requests(BdrvTrackedRequest *self) bool retry; bool waited = false; - if (!bs->serialising_in_flight) { + if (!atomic_read(&bs->serialising_in_flight)) { return false; } diff --git a/include/block/block_int.h b/include/block/block_int.h index a43fe78..7317db6 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -590,10 +590,6 @@ struct BlockDriverState { /* Callback before write request is processed */ NotifierWithReturnList before_write_notifiers; - /* number of in-flight requests; overall and serialising */ - unsigned int in_flight; - unsigned int serialising_in_flight; - bool wakeup; /* Offset after the highest byte written to */ @@ -620,6 +616,12 @@ struct BlockDriverState { */ int copy_on_read; + /* number of in-flight requests; overall and serialising. + * Accessed with atomic ops. + */ + unsigned int in_flight; + unsigned int serialising_in_flight; + /* do we need to tell the quest if we have a volatile write cache? */ int enable_write_cache;