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.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 CDD7EC10DCE for ; Mon, 4 Dec 2023 14:50:18 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.647078.1009773 (Exim 4.92) (envelope-from ) id 1rAAGw-0000Kf-33; Mon, 04 Dec 2023 14:50:10 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 647078.1009773; Mon, 04 Dec 2023 14:50:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rAAGv-0000KY-U2; Mon, 04 Dec 2023 14:50:09 +0000 Received: by outflank-mailman (input) for mailman id 647078; Mon, 04 Dec 2023 14:50:08 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rAAGu-0007Vk-9r for xen-devel@lists.xenproject.org; Mon, 04 Dec 2023 14:50:08 +0000 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 691e95ec-92b4-11ee-9b0f-b553b5be7939; Mon, 04 Dec 2023 15:50:06 +0100 (CET) Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-241-5wDKJD6mPs27fxPG3prMrg-1; Mon, 04 Dec 2023 09:49:58 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4B74B811E8F; Mon, 4 Dec 2023 14:49:57 +0000 (UTC) Received: from localhost (unknown [10.39.192.49]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3903240C6EB9; Mon, 4 Dec 2023 14:49:55 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 691e95ec-92b4-11ee-9b0f-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701701404; 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=q15/3BVVyOaihcucEucNKs/jzap+i7xs4+FWf0/CsZk=; b=Ost3AWy/dHsq1RQsEKl+UDWP48e3cYiFMOCYJmO/kVxeipKWOo/Lkw5lyJB0XEROYe8m6r 0Zb7jCnWL2u8CMMTtCzcKd3uIyN/1QpkxzOo6w781FOzVSw0yh19E8f3Ey+ULesqDedV+p qvgcGNnoGXlcMx++HIzYKuYizMf6YEg= X-MC-Unique: 5wDKJD6mPs27fxPG3prMrg-1 Date: Mon, 4 Dec 2023 09:49:54 -0500 From: Stefan Hajnoczi To: Eric Blake Cc: qemu-devel@nongnu.org, Hanna Reitz , Paul Durrant , Paolo Bonzini , Alberto Garcia , Emanuele Giuseppe Esposito , John Snow , Kevin Wolf , Wen Congyang , qemu-block@nongnu.org, xen-devel@lists.xenproject.org, Coiby Xu , Eduardo Habkost , Xie Changlong , Ari Sundholm , Li Zhijian , Cleber Rosa , Juan Quintela , "Michael S. Tsirkin" , Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= , Jason Wang , Vladimir Sementsov-Ogievskiy , Zhang Chen , Peter Xu , Anthony Perard , Stefano Stabellini , Leonardo Bras , Pavel Dovgalyuk , Fam Zheng , Fabiano Rosas Subject: Re: [PATCH 01/12] virtio-scsi: replace AioContext lock with tmf_bh_lock Message-ID: <20231204144954.GA1492005@fedora> References: <20231129195553.942921-1-stefanha@redhat.com> <20231129195553.942921-2-stefanha@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="xuVVbWEiWN36eeYa" Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 --xuVVbWEiWN36eeYa Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Nov 30, 2023 at 09:25:52AM -0600, Eric Blake wrote: > On Wed, Nov 29, 2023 at 02:55:42PM -0500, Stefan Hajnoczi wrote: > > Protect the Task Management Function BH state with a lock. The TMF BH > > runs in the main loop thread. An IOThread might process a TMF at the > > same time as the TMF BH is running. Therefore tmf_bh_list and tmf_bh > > must be protected by a lock. > >=20 > > Run TMF request completion in the IOThread using aio_wait_bh_oneshot(). > > This avoids more locking to protect the virtqueue and SCSI layer state. >=20 > Are we trying to get this into 8.2? No. 8.2 still has the AioContext lock is therefore safe without this patch. Stefan >=20 > >=20 > > Signed-off-by: Stefan Hajnoczi > > --- > > include/hw/virtio/virtio-scsi.h | 3 +- > > hw/scsi/virtio-scsi.c | 62 ++++++++++++++++++++++----------- > > 2 files changed, 43 insertions(+), 22 deletions(-) > > >=20 > Reviewed-by: Eric Blake >=20 > --=20 > Eric Blake, Principal Software Engineer > Red Hat, Inc. > Virtualization: qemu.org | libguestfs.org >=20 --xuVVbWEiWN36eeYa Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmVt5xIACgkQnKSrs4Gr c8jrKAgAi9Ez+xTcPA2/0XgPvi0dsAshvngJFgGPGKyor2T6HSiEfY5fZnA+zl/Z 6RqIc79YvldlUyqQVTXHU/H0yF/UW4h9d2gz0nlaCBx/1H0xzbAmLUTMW5bGQ/vT N5SCBl6RSfDRmU/eZcbrIqHOaphPCeBt4v6mnfrCF5F9XAS/Iarz7MybbHWnZEq3 93KGFY1LBRQIwp/IhNA+lkMxrysBl5fYLCoKaVxj03r5DSP3c/QwSKcy2jyubAG1 SQS2QRmPHmOOK5jyL2mMs6cnUk8spfmqH9BJl/46nXpvYpJ63m/6ujHjfxGbp9EJ dJdPCfP8N/qcMJGUlSGyGL7UfQp3cQ== =UZuA -----END PGP SIGNATURE----- --xuVVbWEiWN36eeYa--