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 8A939C433F5 for ; Thu, 28 Apr 2022 11:51:26 +0000 (UTC) Received: from localhost ([::1]:53222 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nk2g9-0001v7-N8 for qemu-devel@archiver.kernel.org; Thu, 28 Apr 2022 07:51:25 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39240) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nk2DR-00082I-DW for qemu-devel@nongnu.org; Thu, 28 Apr 2022 07:21:46 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:20449) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nk2DN-0000Kv-Hq for qemu-devel@nongnu.org; Thu, 28 Apr 2022 07:21:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1651144900; 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: in-reply-to:in-reply-to:references:references; bh=nIVqHgu5u0iyjIF6LgD7osVzHb9IxA/ThSUPMBbXoqs=; b=FuQo0H2l/ECbYTGDXx4eNmu+hzgVvupMuChNuG32dHQ95bZLymcxRmR4LgeNd6nO4WtvUB W2TcLJ77XS70o/b/yOEPbU4MI0sIB//XjdFlHn1LHkA8tLPGnbrq4xbApCswkrBpOexpFw WyDeHoRmu+/WAww1n4XV34jqTs2KZJU= 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-395-WXjNYgQXMEuCjo5IsQKcCA-1; Thu, 28 Apr 2022 07:21:36 -0400 X-MC-Unique: WXjNYgQXMEuCjo5IsQKcCA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 759363811F31; Thu, 28 Apr 2022 11:21:36 +0000 (UTC) Received: from localhost (unknown [10.39.195.83]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0B94040314F; Thu, 28 Apr 2022 11:21:35 +0000 (UTC) Date: Thu, 28 Apr 2022 12:21:34 +0100 From: Stefan Hajnoczi To: Emanuele Giuseppe Esposito Subject: Re: [RFC PATCH v2 2/8] coroutine-lock: release lock when restarting all coroutines Message-ID: References: <20220426085114.199647-1-eesposit@redhat.com> <20220426085114.199647-3-eesposit@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="0H+O0UBjKkhRSvg2" Content-Disposition: inline In-Reply-To: <20220426085114.199647-3-eesposit@redhat.com> X-Scanned-By: MIMEDefang 2.85 on 10.11.54.10 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: , Cc: Kevin Wolf , Fam Zheng , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, qemu-devel@nongnu.org, Hanna Reitz , Paolo Bonzini , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --0H+O0UBjKkhRSvg2 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Apr 26, 2022 at 04:51:08AM -0400, Emanuele Giuseppe Esposito wrote: > Current implementation of qemu_co_queue_do_restart > does not releases the lock before calling aio_co_wake. > Most of the time this is fine, but if the coroutine > acquires the lock again then we have a deadlock. >=20 > Instead of duplicating code, use qemu_co_enter_next_impl, since > it implements exactly the same functionality that we > want. >=20 > Signed-off-by: Emanuele Giuseppe Esposito > --- It's unclear whether this patch fixes a bug or introduces a new API that will be used in later patches. The commit message is a bit misleading: existing functions are not changed to release the lock when restarting all coroutines. I think what this commit is actually doing is adding a new API that will be used in later patches? --0H+O0UBjKkhRSvg2 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmJqeL4ACgkQnKSrs4Gr c8hchwf7BKl9H63EhzV7r1PhhJNvtSaX3c2Wc7KQKSSZ1PCMNc2c3rOwWZp2xfKy FEym0/AYFK0YS9bl6rJcApQYm5jWq0sza0gpSObR6D7OQUOK8Ch2ms07BiyZjjrC 8iAro4oQZEBhAsSeVdHJaXL0cMicwSI2HQdsWF2j9CRFZZvV+4Nh95qqVNgNIwCp 1kOpbD38rSrgXUjYPr1qjhg45bEVt1HJRNYY996D3sSLpjPimqjc1TxDW+K9TOaS 9+60trdvvc3kG0s6sVbyMua7KFcK2YsEZo7Rk9HVivzAKZVrcTMWVCu2A7Yr8Ftx glOUUmDJfufrZMdIfA8KR/koOuzR/A== =ePzv -----END PGP SIGNATURE----- --0H+O0UBjKkhRSvg2--