From nobody Tue Nov 4 10:50:34 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1505840543962986.3935547967114; Tue, 19 Sep 2017 10:02:23 -0700 (PDT) Received: from localhost ([::1]:44163 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1duLug-0004q3-RL for importer@patchew.org; Tue, 19 Sep 2017 13:02:22 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40306) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1duLf6-0007aM-2D for qemu-devel@nongnu.org; Tue, 19 Sep 2017 12:46:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1duLf4-0004F2-Vz for qemu-devel@nongnu.org; Tue, 19 Sep 2017 12:46:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44592) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1duLf4-0004Eb-R9 for qemu-devel@nongnu.org; Tue, 19 Sep 2017 12:46:14 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id D0E904E33A; Tue, 19 Sep 2017 16:46:13 +0000 (UTC) Received: from localhost (unknown [10.36.117.0]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4337F5D6A4; Tue, 19 Sep 2017 16:46:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com D0E904E33A Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=cohuck@redhat.com From: Cornelia Huck To: peter.maydell@linaro.org Date: Tue, 19 Sep 2017 18:43:31 +0200 Message-Id: <20170919164337.18555-33-cohuck@redhat.com> In-Reply-To: <20170919164337.18555-1-cohuck@redhat.com> References: <20170919164337.18555-1-cohuck@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 19 Sep 2017 16:46:14 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL v2 32/38] s390x: allow CPU hotplug in random core-id order X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: thuth@redhat.com, david@redhat.com, Cornelia Huck , agraf@suse.de, qemu-devel@nongnu.org, borntraeger@de.ibm.com, rth@twiddle.net Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: David Hildenbrand SCLP correctly indicates the core-id aka. CPU address for each available CPU. As the core-id corresponds to cpu_index, also a newly created kvm vcpu gets assigned this core-id as vcpu id. So SIGP in the kernel works correctly (it uses the vcpu id to lookup the correct CPU). So there should be nothing hindering us from hotplugging CPUs in random core-id order. This now makes sure that the output from "query-hotpluggable-cpus" is completely true. Until now, a specific order is implicit. Performance vice, hotplugging CPUs in non-sequential order might not be the best thing to do, as VCPU lookup inside KVM might be a little slower. But that doesn't hinder us from supporting it. next_core_id is now used by linux user only. Signed-off-by: David Hildenbrand Message-Id: <20170913132417.24384-23-david@redhat.com> Reviewed-by: Igor Mammedov Signed-off-by: Cornelia Huck --- target/s390x/cpu.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c index 5724dffb88..34538c3ab9 100644 --- a/target/s390x/cpu.c +++ b/target/s390x/cpu.c @@ -199,6 +199,7 @@ static void s390_cpu_realizefn(DeviceState *dev, Error = **errp) #else /* implicitly set for linux-user only */ cpu->env.core_id =3D scc->next_core_id; + scc->next_core_id++; #endif =20 if (cpu_exists(cpu->env.core_id)) { @@ -206,12 +207,6 @@ static void s390_cpu_realizefn(DeviceState *dev, Error= **errp) ", it already exists", cpu->env.core_id); goto out; } - if (cpu->env.core_id !=3D scc->next_core_id) { - error_setg(&err, "Unable to add CPU with core-id: %" PRIu32 - ", the next available core-id is %" PRIu32, cpu->env.co= re_id, - scc->next_core_id); - goto out; - } =20 /* sync cs->cpu_index and env->core_id. The latter is needed for TCG. = */ cs->cpu_index =3D env->core_id; @@ -219,7 +214,6 @@ static void s390_cpu_realizefn(DeviceState *dev, Error = **errp) if (err !=3D NULL) { goto out; } - scc->next_core_id++; =20 #if !defined(CONFIG_USER_ONLY) qemu_register_reset(s390_cpu_machine_reset_cb, cpu); --=20 2.13.5