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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 98B56CA9EA0 for ; Fri, 25 Oct 2019 15:27:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7893220679 for ; Fri, 25 Oct 2019 15:27:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440750AbfJYP1n (ORCPT ); Fri, 25 Oct 2019 11:27:43 -0400 Received: from foss.arm.com ([217.140.110.172]:42164 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731226AbfJYP1l (ORCPT ); Fri, 25 Oct 2019 11:27:41 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2665C328; Fri, 25 Oct 2019 08:27:41 -0700 (PDT) Received: from arrakis.emea.arm.com (arrakis.cambridge.arm.com [10.1.197.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 596103F71A; Fri, 25 Oct 2019 08:27:39 -0700 (PDT) Date: Fri, 25 Oct 2019 16:27:37 +0100 From: Catalin Marinas To: Yunfeng Ye Cc: will@kernel.org, kstewart@linuxfoundation.org, sudeep.holla@arm.com, gregkh@linuxfoundation.org, lorenzo.pieralisi@arm.com, tglx@linutronix.de, David.Laight@ACULAB.COM, mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, "linux-kernel@vger.kernel.org" , hushiyuan@huawei.com, wuyun.wu@huawei.com, linfeilong@huawei.com Subject: Re: [PATCH v6] arm64: psci: Reduce the waiting time for cpu_psci_cpu_kill() Message-ID: <20191025152737.GN3328@arrakis.emea.arm.com> References: <0842431c-fa15-2ba1-ae6d-c1fea157941f@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0842431c-fa15-2ba1-ae6d-c1fea157941f@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 21, 2019 at 07:31:21PM +0800, Yunfeng Ye wrote: > In cases like suspend-to-disk and suspend-to-ram, a large number of CPU > cores need to be shut down. At present, the CPU hotplug operation is > serialised, and the CPU cores can only be shut down one by one. In this > process, if PSCI affinity_info() does not return LEVEL_OFF quickly, > cpu_psci_cpu_kill() needs to wait for 10ms. If hundreds of CPU cores > need to be shut down, it will take a long time. > > Normally, there is no need to wait 10ms in cpu_psci_cpu_kill(). So > change the wait interval from 10 ms to max 1 ms and use usleep_range() > instead of msleep() for more accurate timer. > > In addition, reducing the time interval will increase the messages > output, so remove the "Retry ..." message, instead, track time and > output to the the sucessful message. > > Signed-off-by: Yunfeng Ye > Reviewed-by: Sudeep Holla Queued for 5.5. Thanks. -- Catalin