From patchwork Wed May 10 20:35:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 13237236 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 BC24CC77B7D for ; Wed, 10 May 2023 20:38:00 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pwqYK-0005KD-1u; Wed, 10 May 2023 16:36:48 -0400 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 1pwqY8-0005EV-MF for qemu-devel@nongnu.org; Wed, 10 May 2023 16:36:37 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pwqY5-0003MV-B7 for qemu-devel@nongnu.org; Wed, 10 May 2023 16:36:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683750992; 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=F3xsJyxmeHSomo74+D4aggMuwldNR5lEhLMTiDrQpX4=; b=EBcm4dcsSg3vSqOMqzlo8yCldJEMlEbaVm4awm5gHcNKNCCFgcnvxCQ9nPa/m728wj4rFC OLINC4lIr+ldUb/wNdblpoYUuDzzUd/YtGHBoDbvNDbdxkuNljfagg4L3d2t5DStvKpxwS P5L/GE3Xy++WUXsvbdEdLCeixz+P1Cs= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-441-peVt73ibMGu9AjjBKAg3bw-1; Wed, 10 May 2023 16:36:29 -0400 X-MC-Unique: peVt73ibMGu9AjjBKAg3bw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 27556381D1E4; Wed, 10 May 2023 20:36:29 +0000 (UTC) Received: from merkur.fritz.box (unknown [10.39.194.148]) by smtp.corp.redhat.com (Postfix) with ESMTP id E8A741121314; Wed, 10 May 2023 20:36:27 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, hreitz@redhat.com, stefanha@redhat.com, f.ebner@proxmox.com, qemu-devel@nongnu.org Subject: [PATCH 5/8] test-bdrv-drain: Take graph lock more selectively Date: Wed, 10 May 2023 22:35:58 +0200 Message-Id: <20230510203601.418015-6-kwolf@redhat.com> In-Reply-To: <20230510203601.418015-1-kwolf@redhat.com> References: <20230510203601.418015-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=kwolf@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, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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 If we take a reader lock, we can't call any functions that take a writer lock internally without causing deadlocks once the reader lock is actually enforced in the main thread, too. Take the reader lock only where it is actually needed. Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake --- tests/unit/test-bdrv-drain.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index 9a4c5e59d6..ae4299ccfa 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -1004,8 +1004,6 @@ static void coroutine_fn test_co_delete_by_drain(void *opaque) void *buffer = g_malloc(65536); QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buffer, 65536); - GRAPH_RDLOCK_GUARD(); - /* Pretend some internal write operation from parent to child. * Important: We have to read from the child, not from the parent! * Draining works by first propagating it all up the tree to the @@ -1014,7 +1012,9 @@ static void coroutine_fn test_co_delete_by_drain(void *opaque) * everything will be drained before we go back down the tree, but * we do not want that. We want to be in the middle of draining * when this following requests returns. */ + bdrv_graph_co_rdlock(); bdrv_co_preadv(tts->wait_child, 0, 65536, &qiov, 0); + bdrv_graph_co_rdunlock(); g_assert_cmpint(bs->refcnt, ==, 1);