From nobody Sun Feb 8 17:04:41 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of redhat.com designates 170.10.129.124 as permitted sender) client-ip=170.10.129.124; envelope-from=libvir-list-bounces@redhat.com; helo=us-smtp-delivery-124.mimecast.com; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1665064212; cv=none; d=zohomail.com; s=zohoarc; b=MjcWwddJF6i254zSRgAYKAviUml3PvLDzUyPpF7OqmOKkGt8tg8nqqPDIULBa7vF+nl7vigYdItGVoPp5SEPyYJmRn46ihjvMBGep18doyi3Iv4HZcXMW9V49QIex85X+dVR6sxU5qzZiMAZlejcQFWe5YKa/uL9hGIxk5TMFEU= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1665064212; h=Content-Type:Content-Transfer-Encoding:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=qqHoBQvGQqZilgM51ry4EgEFviFnExhL447xGUNxZec=; b=F8AF+agbKf5HyjokPBj44hF4KY4a0z+Okk9XX9E/VNAwPrxGn7wc9IbrVnNJU8aIdEmHDBG7S2mf9MptPzQRS0BI05he6YANyxEQ6D3KsyEQCI81ltyJYU460q2s5yLTXBzvR58DC5ZUVDR+VCPEjmtnaFn96OvZ7tcH3TiHBG0= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by mx.zohomail.com with SMTPS id 1665064212606442.88169019294935; Thu, 6 Oct 2022 06:50:12 -0700 (PDT) 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-513-LIqYJAJtP4u9fEfklNqBIw-1; Thu, 06 Oct 2022 09:50:07 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id F31321C06EDD; Thu, 6 Oct 2022 13:49:59 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (unknown [10.30.29.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id DED6D1121339; Thu, 6 Oct 2022 13:49:59 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (localhost [IPv6:::1]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id A8D3F1946589; Thu, 6 Oct 2022 13:49:59 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id 1A90C19465A4 for ; Thu, 6 Oct 2022 13:49:58 +0000 (UTC) Received: by smtp.corp.redhat.com (Postfix) id 0F01114588B3; Thu, 6 Oct 2022 13:49:58 +0000 (UTC) Received: from maggie.redhat.com (unknown [10.43.2.39]) by smtp.corp.redhat.com (Postfix) with ESMTP id AB7D114588B4 for ; Thu, 6 Oct 2022 13:49:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1665064211; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=qqHoBQvGQqZilgM51ry4EgEFviFnExhL447xGUNxZec=; b=K1lcYI1bDu4htYPhcD2DaWQ9mHwaJS4DkeJt773/MtPqcjNvyfh1oViHAbsPy5AeA14Mf9 w3NolHiGsts0LWEgjS7xtHKJDH/iY0ErnIkCHE7PW0QQ2vGCozZLAQVB/hVPYX4bcwpfz9 jKfhuN7V8DJDIo317bx4bg+TVsUe+0A= X-MC-Unique: LIqYJAJtP4u9fEfklNqBIw-1 X-Original-To: libvir-list@listman.corp.redhat.com From: Michal Privoznik To: libvir-list@redhat.com Subject: [PATCH v4 7/8] qemu: Enable SCHED_CORE for vCPUs Date: Thu, 6 Oct 2022 15:49:49 +0200 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libvir-list-bounces@redhat.com Sender: "libvir-list" X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1665064212971100007 For QEMU_SCHED_CORE_VCPUS case, the vCPU threads should be placed all into one scheduling group, but not the emulator or any of its threads. Therefore, as soon as vCPU TIDs are detected, fork off a child which then creates a separate scheduling group and adds all vCPU threads into it. Please note, this commit only handles the cold boot case. Hotplug is going to be implemented in the next commit. Signed-off-by: Michal Privoznik Reviewed-by: Daniel P. Berrang=C3=A9 --- src/qemu/qemu_process.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index 22845423ce..32136978a9 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -5860,9 +5860,44 @@ qemuProcessSetupVcpu(virDomainObj *vm, } =20 =20 +static int +qemuProcessSetupAllVcpusSchedCoreHelper(pid_t ppid G_GNUC_UNUSED, + void *opaque) +{ + virDomainObj *vm =3D opaque; + size_t i; + + /* Since we are setting all vCPU threads at once and from a forked off + * child, we don't need the dummy schedCoreChildPID and can create one= on + * our own. */ + if (virProcessSchedCoreCreate() < 0) { + virReportSystemError(errno, "%s", + _("Unable to set SCHED_CORE")); + + return -1; + } + + for (i =3D 0; i < virDomainDefGetVcpusMax(vm->def); i++) { + pid_t vcpupid =3D qemuDomainGetVcpuPid(vm, i); + + if (vcpupid > 0 && + virProcessSchedCoreShareTo(vcpupid) < 0) { + virReportSystemError(errno, + _("unable to share scheduling cookie to %= lld"), + (long long) vcpupid); + return -1; + } + } + + return 0; +} + + static int qemuProcessSetupVcpus(virDomainObj *vm) { + qemuDomainObjPrivate *priv =3D vm->privateData; + g_autoptr(virQEMUDriverConfig) cfg =3D virQEMUDriverGetConfig(priv->dr= iver); virDomainVcpuDef *vcpu; unsigned int maxvcpus =3D virDomainDefGetVcpusMax(vm->def); size_t i; @@ -5905,6 +5940,10 @@ qemuProcessSetupVcpus(virDomainObj *vm) return -1; } =20 + if (cfg->schedCore =3D=3D QEMU_SCHED_CORE_VCPUS && + virProcessRunInFork(qemuProcessSetupAllVcpusSchedCoreHelper, vm) <= 0) + return -1; + return 0; } =20 --=20 2.35.1