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 X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5E8FC4321D for ; Mon, 20 Aug 2018 18:05:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AAF442173A for ; Mon, 20 Aug 2018 18:05:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AAF442173A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726595AbeHTVVx (ORCPT ); Mon, 20 Aug 2018 17:21:53 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:59846 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726106AbeHTVVw (ORCPT ); Mon, 20 Aug 2018 17:21:52 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w7KI4oYJ086778 for ; Mon, 20 Aug 2018 14:05:13 -0400 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0b-001b2d01.pphosted.com with ESMTP id 2m006xdy88-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 20 Aug 2018 14:05:13 -0400 Received: from localhost by e06smtp01.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 20 Aug 2018 19:05:07 +0100 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w7KI56KI44892188 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 20 Aug 2018 18:05:06 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 713605204E; Mon, 20 Aug 2018 21:05:07 +0100 (BST) Received: from linux.vnet.ibm.com (unknown [9.40.192.68]) by d06av21.portsmouth.uk.ibm.com (Postfix) with SMTP id 6E44F52050; Mon, 20 Aug 2018 21:05:05 +0100 (BST) Date: Mon, 20 Aug 2018 11:05:03 -0700 From: Srikar Dronamraju To: "Gautham R. Shenoy" Cc: Michael Ellerman , Benjamin Herrenschmidt , Michael Neuling , Vaidyanathan Srinivasan , Akshay Adiga , Shilpasri G Bhat , "Oliver O'Halloran" , Nicholas Piggin , Murilo Opsfelder Araujo , Anton Blanchard , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 2/2] powerpc: Use cpu_smallcore_sibling_mask at SMT level on bigcores Reply-To: Srikar Dronamraju References: <1534743704-4760-1-git-send-email-ego@linux.vnet.ibm.com> <1534743704-4760-3-git-send-email-ego@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1534743704-4760-3-git-send-email-ego@linux.vnet.ibm.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-TM-AS-GCONF: 00 x-cbid: 18082018-4275-0000-0000-000002AC580A X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18082018-4276-0000-0000-000037B58B40 Message-Id: <20180820180503.GB23117@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-08-20_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=800 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1808200187 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Gautham R. Shenoy [2018-08-20 11:11:44]: > From: "Gautham R. Shenoy" > > Each of the SMT4 cores forming a big-core are more or less independent > units. Thus when multiple tasks are scheduled to run on the fused > core, we get the best performance when the tasks are spread across the > pair of SMT4 cores. > > This patch achieves this by setting the SMT level mask to correspond > to the smallcore sibling mask on big-core systems. This patch also > ensures that while checked for shared-caches on big-core system, we > use the smallcore_sibling_mask to compare with the l2_cache_mask. > This ensure that the CACHE level sched-domain is created, whose groups > correspond to the threads of the big-core. > > With this patch, the SMT sched-domain with SMT=8,4,2 on big-core > systems are as follows: Reviewed-by: Srikar Dronamraju