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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5262C433ED for ; Mon, 10 May 2021 09:08:09 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 713EC613DE for ; Mon, 10 May 2021 09:08:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 713EC613DE Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:37464 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lg1tY-0007Iw-Gl for qemu-devel@archiver.kernel.org; Mon, 10 May 2021 05:08:08 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56308) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lg1mG-0004CN-Jr for qemu-devel@nongnu.org; Mon, 10 May 2021 05:00:38 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:52342) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lg1mF-00068x-3c for qemu-devel@nongnu.org; Mon, 10 May 2021 05:00:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1620637234; h=from:from: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; bh=T6kPlDFfZY6SAUMlloEcSFKJbzHvBXzvBVlEynO4IUQ=; b=R67uKwNAY+rhzkSpd6QVWZlQw6AHM7caH29PjNWykcXz0PoZt/F58guT2jMQdPQDisdGI/ mX6ajGo/an4yltyG9iF0yqTJtsEMIaMxvJ2tSIM4achOnImNNlluNJsc4jLVRdKTU5ap7y y0uj7smTFRbiyf6sQUbinZfMOupVPtc= 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-141-dnpzblSOPEKQ2W4AVhWGNg-1; Mon, 10 May 2021 05:00:02 -0400 X-MC-Unique: dnpzblSOPEKQ2W4AVhWGNg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5200B107ACE3; Mon, 10 May 2021 09:00:01 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-113-184.ams2.redhat.com [10.36.113.184]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2CF91627DC; Mon, 10 May 2021 08:59:59 +0000 (UTC) From: Emanuele Giuseppe Esposito To: qemu-block@nongnu.org Subject: [PATCH 5/6] co-shared-resource: protect with a mutex Date: Mon, 10 May 2021 10:59:40 +0200 Message-Id: <20210510085941.22769-6-eesposit@redhat.com> In-Reply-To: <20210510085941.22769-1-eesposit@redhat.com> References: <20210510085941.22769-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eesposit@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=216.205.24.124; envelope-from=eesposit@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.699, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Emanuele Giuseppe Esposito , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, Max Reitz , Stefan Hajnoczi , Paolo Bonzini , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" co-shared-resource is currently not thread-safe, as also reported in co-shared-resource.h. Add a QemuMutex because co_try_get_from_shres can also be invoked from non-coroutine context. Signed-off-by: Emanuele Giuseppe Esposito --- util/qemu-co-shared-resource.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/util/qemu-co-shared-resource.c b/util/qemu-co-shared-resource.c index 1c83cd9d29..c455d02a1e 100644 --- a/util/qemu-co-shared-resource.c +++ b/util/qemu-co-shared-resource.c @@ -32,6 +32,7 @@ struct SharedResource { uint64_t available; CoQueue queue; + QemuMutex lock; }; SharedResource *shres_create(uint64_t total) @@ -40,17 +41,23 @@ SharedResource *shres_create(uint64_t total) s->total = s->available = total; qemu_co_queue_init(&s->queue); + qemu_mutex_init(&s->lock); return s; } void shres_destroy(SharedResource *s) { - assert(s->available == s->total); + WITH_QEMU_LOCK_GUARD(&s->lock) { + assert(s->available == s->total); + } + + qemu_mutex_destroy(&s->lock); g_free(s); } -bool co_try_get_from_shres(SharedResource *s, uint64_t n) +/* Called with lock held */ +static bool co_try_get_from_shres_unlocked(SharedResource *s, uint64_t n) { if (s->available >= n) { s->available -= n; @@ -60,16 +67,27 @@ bool co_try_get_from_shres(SharedResource *s, uint64_t n) return false; } +bool co_try_get_from_shres(SharedResource *s, uint64_t n) +{ + bool res; + QEMU_LOCK_GUARD(&s->lock); + res = co_try_get_from_shres_unlocked(s, n); + + return res; +} + void coroutine_fn co_get_from_shres(SharedResource *s, uint64_t n) { + QEMU_LOCK_GUARD(&s->lock); assert(n <= s->total); - while (!co_try_get_from_shres(s, n)) { - qemu_co_queue_wait(&s->queue, NULL); + while (!co_try_get_from_shres_unlocked(s, n)) { + qemu_co_queue_wait(&s->queue, &s->lock); } } void coroutine_fn co_put_to_shres(SharedResource *s, uint64_t n) { + QEMU_LOCK_GUARD(&s->lock); assert(s->total - s->available >= n); s->available += n; qemu_co_queue_restart_all(&s->queue); -- 2.30.2