From patchwork Fri Mar 22 06:25:29 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Abhishek Goel X-Patchwork-Id: 10864937 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BD1DB922 for ; Fri, 22 Mar 2019 06:26:13 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 98EEF2A5DD for ; Fri, 22 Mar 2019 06:26:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8BB822A5E1; Fri, 22 Mar 2019 06:26:13 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7AB632A5DD for ; Fri, 22 Mar 2019 06:26:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726096AbfCVG0K (ORCPT ); Fri, 22 Mar 2019 02:26:10 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:37862 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726205AbfCVG0K (ORCPT ); Fri, 22 Mar 2019 02:26:10 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x2M6KLoY071805 for ; Fri, 22 Mar 2019 02:26:08 -0400 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0b-001b2d01.pphosted.com with ESMTP id 2rcs7waer1-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 22 Mar 2019 02:26:08 -0400 Received: from localhost by e06smtp05.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) Fri, 22 Mar 2019 06:25:55 -0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x2M6Q3G320775098 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 22 Mar 2019 06:26:03 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6C20AAE053; Fri, 22 Mar 2019 06:26:03 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4FEB0AE04D; Fri, 22 Mar 2019 06:26:02 +0000 (GMT) Received: from boston16h.aus.stglabs.ibm.com (unknown [9.3.23.78]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 22 Mar 2019 06:26:02 +0000 (GMT) From: Abhishek Goel To: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-pm@vger.kernel.org Cc: rjw@rjwysocki.net, daniel.lezcano@linaro.org, mpe@ellerman.id.au, Abhishek Goel Subject: [PATCH 1/2] cpuidle : auto-promotion for cpuidle states Date: Fri, 22 Mar 2019 01:25:29 -0500 X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190322062530.7586-1-huntbag@linux.vnet.ibm.com> References: <20190322062530.7586-1-huntbag@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 19032206-0020-0000-0000-000003263E74 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19032206-0021-0000-0000-0000217867D0 Message-Id: <20190322062530.7586-2-huntbag@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-03-22_04:,, 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=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1903220048 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently, the cpuidle governors (menu /ladder) determine what idle state an idling CPU should enter into based on heuristics that depend on the idle history on that CPU. Given that no predictive heuristic is perfect, there are cases where the governor predicts a shallow idle state, hoping that the CPU will be busy soon. However, if no new workload is scheduled on that CPU in the near future, the CPU will end up in the shallow state. In case of POWER, this is problematic, when the predicted state in the aforementioned scenario is a lite stop state, as such lite states will inhibit SMT folding, thereby depriving the other threads in the core from using the core resources. To address this, such lite states need to be autopromoted. The cpuidle- core can queue timer to correspond with the residency value of the next available state. Thus leading to auto-promotion to a deeper idle state as soon as possible. Signed-off-by: Abhishek Goel --- drivers/cpuidle/cpuidle.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 2406e2655..c4d1c1b38 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -584,11 +584,8 @@ static void __cpuidle_unregister_device(struct cpuidle_device *dev) static void __cpuidle_device_init(struct cpuidle_device *dev) { - int i; memset(dev->states_usage, 0, sizeof(dev->states_usage)); dev->last_residency = 0; - for (i = 0; i < CPUIDLE_STATE_MAX; i++) - dev->states_usage[i].disable = true; } /**