From nobody Mon May 6 18:27:17 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; envelope-from=libvir-list-bounces@redhat.com; helo=mx1.redhat.com; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass(p=none dis=none) header.from=redhat.com Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mx.zohomail.com with SMTPS id 1536067859175725.8458371242576; Tue, 4 Sep 2018 06:30:59 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B79133003064; Tue, 4 Sep 2018 13:30:54 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 796CB60E3E; Tue, 4 Sep 2018 13:30:54 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id E3A45181A13A; Tue, 4 Sep 2018 13:30:53 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id w84DUfX5001378 for ; Tue, 4 Sep 2018 09:30:41 -0400 Received: by smtp.corp.redhat.com (Postfix) id 880302023416; Tue, 4 Sep 2018 13:30:41 +0000 (UTC) Received: from dell-r430-03.lab.eng.brq.redhat.com (dell-r430-03.lab.eng.brq.redhat.com [10.37.153.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id BC6EE2023417; Tue, 4 Sep 2018 13:30:40 +0000 (UTC) From: Igor Mammedov To: qemu-devel@nongnu.org Date: Tue, 4 Sep 2018 15:22:35 +0200 Message-Id: <1536067356-44609-2-git-send-email-imammedo@redhat.com> In-Reply-To: <1536067356-44609-1-git-send-email-imammedo@redhat.com> References: <1536067356-44609-1-git-send-email-imammedo@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-loop: libvir-list@redhat.com Cc: libvir-list@redhat.com, drjones@redhat.com, ehabkost@redhat.com Subject: [libvirt] [PATCH v5 1/2] vl.c deprecate incorrect CPUs topology X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Tue, 04 Sep 2018 13:30:55 +0000 (UTC) X-ZohoMail: RDMRC_0 RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" -smp [cpus],sockets/cores/threads[,maxcpus] should describe topology so that total number of logical CPUs [sockets * cores * threads] would be equal to [maxcpus], however historically we didn't have such check in QEMU and it is possible to start VM with an invalid topology. Deprecate invalid options combination so we can make sure that the topology VM started with is always correct in the future. Users with an invalid sockets/cores/threads/maxcpus values should fix their CLI to make sure that [sockets * cores * threads] =3D=3D [maxcpus] Signed-off-by: Igor Mammedov Reviewed-by: Andrew Jones Reviewed-by: Eduardo Habkost --- v5: - extend deprecation doc, adding that maxcpus should be multiple of present on CLI [sockets/cores/threads] options (Eduardo Habkost ) v4: - missed dot comment, fix it with s/./,/ (Andrew Jones ) v3: - more spelling fixes (Andrew Jones ) - place deprecation check after (sockets * cores * threads > max_cpus) ch= eck (Eduardo Habkost ) v2: - spelling&&co fixes (Andrew Jones ) --- qemu-deprecated.texi | 19 +++++++++++++++++++ vl.c | 7 +++++++ 2 files changed, 26 insertions(+) diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi index 87212b6..827c3ce 100644 --- a/qemu-deprecated.texi +++ b/qemu-deprecated.texi @@ -159,6 +159,25 @@ The 'file' driver for drives is no longer appropriate = for character or host devices and will only accept regular files (S_IFREG). The correct driver for these file types is 'host_cdrom' or 'host_device' as appropriate. =20 +@subsection -smp X,[socket=3Da,core=3Db,thread=3Dc],maxcpus=3DY (since 3.1) + +CPU topology properties should describe whole machine topology including +possible CPUs, but historically it was possible to start QEMU with +an incorrect topology where + sockets * cores * threads >=3D X && X < maxcpus +which could lead to an incorrect topology enumeration by the guest. +Support for invalid topologies will be removed, the user must ensure +topologies described with -smp include all possible cpus, i.e. + sockets * cores * threads =3D=3D maxcpus +Note: it's assumed that maxcpus value must be multiple of the topology +options present on command line to avoid creating an invalid topology. +If maxcpus isn't be multiple of present topology options then the condition +(sockets * cores * threads =3D=3D maxcpus) can't be satisfied and it will +trigger deprecation warning which later will be converted to a error. +If you get deprecation warning it's recommended to explicitly specify +a correct topology to make warning go away and ensure that it will +continue working in the future. + @section QEMU Machine Protocol (QMP) commands =20 @subsection block-dirty-bitmap-add "autoload" parameter (since 2.12.0) diff --git a/vl.c b/vl.c index 5ba06ad..7fd700e 100644 --- a/vl.c +++ b/vl.c @@ -1246,6 +1246,13 @@ static void smp_parse(QemuOpts *opts) exit(1); } =20 + if (sockets * cores * threads !=3D max_cpus) { + warn_report("Invalid CPU topology deprecated: " + "sockets (%u) * cores (%u) * threads (%u) " + "!=3D maxcpus (%u)", + sockets, cores, threads, max_cpus); + } + smp_cpus =3D cpus; smp_cores =3D cores; smp_threads =3D threads; --=20 2.7.4 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list From nobody Mon May 6 18:27:17 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; envelope-from=libvir-list-bounces@redhat.com; helo=mx1.redhat.com; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass(p=none dis=none) header.from=redhat.com Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mx.zohomail.com with SMTPS id 1536067863024604.2587186980103; Tue, 4 Sep 2018 06:31:03 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 73E7B432D1; Tue, 4 Sep 2018 13:31:00 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 22CF7308BDAF; Tue, 4 Sep 2018 13:31:00 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id A82C0181A439; Tue, 4 Sep 2018 13:30:59 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id w84DUgXX001384 for ; Tue, 4 Sep 2018 09:30:42 -0400 Received: by smtp.corp.redhat.com (Postfix) id 8FE722027069; Tue, 4 Sep 2018 13:30:42 +0000 (UTC) Received: from dell-r430-03.lab.eng.brq.redhat.com (dell-r430-03.lab.eng.brq.redhat.com [10.37.153.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id C343E202322B; Tue, 4 Sep 2018 13:30:41 +0000 (UTC) From: Igor Mammedov To: qemu-devel@nongnu.org Date: Tue, 4 Sep 2018 15:22:36 +0200 Message-Id: <1536067356-44609-3-git-send-email-imammedo@redhat.com> In-Reply-To: <1536067356-44609-1-git-send-email-imammedo@redhat.com> References: <1536067356-44609-1-git-send-email-imammedo@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-loop: libvir-list@redhat.com Cc: libvir-list@redhat.com, drjones@redhat.com, ehabkost@redhat.com Subject: [libvirt] [PATCH v5 2/2] vl:c: make sure that sockets are calculated correctly in '-smp X' case X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.24 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Tue, 04 Sep 2018 13:31:01 +0000 (UTC) X-ZohoMail: RDMRC_0 RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" commit (5cdc9b76e3 vl.c: Remove dead assignment) removed sockets calculation when 'sockets' weren't provided on CLI since there wasn't any users for it back then. Exiting checks are neither reachable } else if (sockets * cores * threads < cpus) { or nor triggable if (sockets * cores * threads > max_cpus) so we weren't noticing wrong topology since then, since users recalculate sockets adhoc on their own. However with deprecation check it becomes noticable, for example -smp 2 will start printing warning: "warning: Invalid CPU topology deprecated: sockets (1) * cores (1) * thre= ads (1) !=3D maxcpus (2)" calculating sockets if they weren't specified. Fix it by returning back sockets calculation if it's omited on CLI. Signed-off-by: Igor Mammedov Reviewed-by: Andrew Jones --- vl.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/vl.c b/vl.c index 7fd700e..333d638 100644 --- a/vl.c +++ b/vl.c @@ -1210,11 +1210,14 @@ static void smp_parse(QemuOpts *opts) =20 /* compute missing values, prefer sockets over cores over threads = */ if (cpus =3D=3D 0 || sockets =3D=3D 0) { - sockets =3D sockets > 0 ? sockets : 1; cores =3D cores > 0 ? cores : 1; threads =3D threads > 0 ? threads : 1; if (cpus =3D=3D 0) { + sockets =3D sockets > 0 ? sockets : 1; cpus =3D cores * threads * sockets; + } else { + max_cpus =3D qemu_opt_get_number(opts, "maxcpus", cpus); + sockets =3D !sockets ? max_cpus / (cores * threads) : sock= ets; } } else if (cores =3D=3D 0) { threads =3D threads > 0 ? threads : 1; --=20 2.7.4 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list