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 BDB0DC54E5D for ; Mon, 18 Mar 2024 17:58:32 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rmHEW-0000VN-Oc; Mon, 18 Mar 2024 13:57:12 -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 1rmHET-0000Tm-Nm for qemu-devel@nongnu.org; Mon, 18 Mar 2024 13:57:09 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rmHES-00077n-7m for qemu-devel@nongnu.org; Mon, 18 Mar 2024 13:57:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710784627; 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=/FdiF6Ay0Y//kEppiR8e/bNkgh8x74HG5F3qOJ903Cc=; b=W25HwQM5wKO3Ejco9q5f5YJk770JzKy1xzRNwXs9xq6b9D+8OR+rt1i+l9QjQUzPgzwzC5 2Blv5ytXvQlUmv5wLZgC4LruWzR7Cowh29ZhIcnqqMixmjhqFPlGmWjwKy0jcn67RazVG/ LbvuYtsT9gIh21SveWpCVmflSOAUFbM= 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-198-dWQPopGVOFSVcJpxmYIW0g-1; Mon, 18 Mar 2024 13:57:04 -0400 X-MC-Unique: dWQPopGVOFSVcJpxmYIW0g-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (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 C7B3B185A789; Mon, 18 Mar 2024 17:57:03 +0000 (UTC) Received: from thuth-p1g4.redhat.com (unknown [10.39.192.155]) by smtp.corp.redhat.com (Postfix) with ESMTP id 027892166B34; Mon, 18 Mar 2024 17:57:01 +0000 (UTC) From: Thomas Huth To: qemu-devel@nongnu.org Cc: Peter Maydell , Claudio Fontana , Nina Schoetterl-Glausch , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Subject: [PULL 1/4] docs/s390: clarify even more that cpu-topology is KVM-only Date: Mon, 18 Mar 2024 18:56:52 +0100 Message-ID: <20240318175655.756084-2-thuth@redhat.com> In-Reply-To: <20240318175655.756084-1-thuth@redhat.com> References: <20240318175655.756084-1-thuth@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.6 Received-SPF: pass client-ip=170.10.133.124; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.374, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, 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 From: Claudio Fontana At least for now cpu-topology is implemented only for KVM. We already say this, but this tries to be more explicit, and also show it in the examples. This adds a new reference in the introduction that we can point to, whenever we need to reference accelerators and how to select them. Signed-off-by: Claudio Fontana Message-ID: <20240314172218.16478-1-cfontana@suse.de> Reviewed-by: Nina Schoetterl-Glausch Tested-by: Nina Schoetterl-Glausch Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Thomas Huth --- docs/system/introduction.rst | 2 ++ docs/system/s390x/cpu-topology.rst | 14 ++++++++------ 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/docs/system/introduction.rst b/docs/system/introduction.rst index 51ac132d6c..746707eb00 100644 --- a/docs/system/introduction.rst +++ b/docs/system/introduction.rst @@ -1,6 +1,8 @@ Introduction ============ +.. _Accelerators: + Virtualisation Accelerators --------------------------- diff --git a/docs/system/s390x/cpu-topology.rst b/docs/system/s390x/cpu-topology.rst index 5133fdc362..d5b506ee5c 100644 --- a/docs/system/s390x/cpu-topology.rst +++ b/docs/system/s390x/cpu-topology.rst @@ -25,17 +25,19 @@ monitor polarization changes, see ``docs/devel/s390-cpu-topology.rst``. Prerequisites ------------- -To use the CPU topology, you need to run with KVM on a s390x host that -uses the Linux kernel v6.0 or newer (which provide the so-called +To use the CPU topology, you currently need to choose the KVM accelerator. +See :ref:`Accelerators` for more details about accelerators and how to select them. + +The s390x host needs to use a Linux kernel v6.0 or newer (which provides the so-called ``KVM_CAP_S390_CPU_TOPOLOGY`` capability that allows QEMU to signal the CPU topology facility via the so-called STFLE bit 11 to the VM). Enabling CPU topology --------------------- -Currently, CPU topology is only enabled in the host model by default. +Currently, CPU topology is enabled by default only in the "host" CPU model. -Enabling CPU topology in a CPU model is done by setting the CPU flag +Enabling CPU topology in another CPU model is done by setting the CPU flag ``ctop`` to ``on`` as in: .. code-block:: bash @@ -132,7 +134,7 @@ In the following machine we define 8 sockets with 4 cores each. .. code-block:: bash - $ qemu-system-s390x -m 2G \ + $ qemu-system-s390x -accel kvm -m 2G \ -cpu gen16b,ctop=on \ -smp cpus=5,sockets=8,cores=4,maxcpus=32 \ -device host-s390x-cpu,core-id=14 \ @@ -227,7 +229,7 @@ with vertical high entitlement. .. code-block:: bash - $ qemu-system-s390x -m 2G \ + $ qemu-system-s390x -accel kvm -m 2G \ -cpu gen16b,ctop=on \ -smp cpus=1,sockets=8,cores=4,maxcpus=32 \ \ -- 2.44.0