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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 87678C4332F for ; Tue, 8 Nov 2022 21:22:44 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1osW16-0005OG-ET; Tue, 08 Nov 2022 16:20:20 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1osW0w-0005FY-4Q for qemu-devel@nongnu.org; Tue, 08 Nov 2022 16:20:13 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1osW0t-00009S-U1 for qemu-devel@nongnu.org; Tue, 08 Nov 2022 16:20:09 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1667942407; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VQ3ATQgKtUyo3XXFzYY5Hl43Lj2yTiPHOQSl+WRJnsw=; b=Oy8SLnjbxwDWcynUAkWOZGEJnJzuTNVs30Lng83TFokdn83Ur9BVYUCO/jcaB1SpaW8JjE KP/h4y8nzOw6PhDti2uzGKZi/Ut3kLbYQC/m8yAYUeJCYX0rVrgzZn7jNu1mhTLgM4dOPK F4ZtUW24BY6bI9UEdf0DVEqimDRkBZg= 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-252-SN4d4uxvM_-o4ZRA5swXig-1; Tue, 08 Nov 2022 16:20:03 -0500 X-MC-Unique: SN4d4uxvM_-o4ZRA5swXig-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 00B3E185A7AA; Tue, 8 Nov 2022 21:20:03 +0000 (UTC) Received: from localhost (unknown [10.39.192.85]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6A0F54C819; Tue, 8 Nov 2022 21:20:02 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Emanuele Giuseppe Esposito , "Michael S. Tsirkin" , qemu-block@nongnu.org, Kevin Wolf , Hanna Reitz , Paolo Bonzini , Fam Zheng , Stefan Hajnoczi Subject: [PATCH 8/8] virtio-blk: minimize virtio_blk_reset() AioContext lock region Date: Tue, 8 Nov 2022 16:19:30 -0500 Message-Id: <20221108211930.876142-9-stefanha@redhat.com> In-Reply-To: <20221108211930.876142-1-stefanha@redhat.com> References: <20221108211930.876142-1-stefanha@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org blk_drain() needs the lock because it calls AIO_WAIT_WHILE(). The s->rq loop doesn't need the lock because dataplane has been stopped when virtio_blk_reset() is called. Signed-off-by: Stefan Hajnoczi --- hw/block/virtio-blk.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 771d87cfbe..0b411b3065 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -898,6 +898,7 @@ static void virtio_blk_reset(VirtIODevice *vdev) ctx = blk_get_aio_context(s->blk); aio_context_acquire(ctx); blk_drain(s->blk); + aio_context_release(ctx); /* We drop queued requests after blk_drain() because blk_drain() itself can * produce them. */ @@ -908,8 +909,6 @@ static void virtio_blk_reset(VirtIODevice *vdev) virtio_blk_free_request(req); } - aio_context_release(ctx); - assert(!s->dataplane_started); blk_set_enable_write_cache(s->blk, s->original_wce); } -- 2.38.1