From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754693AbcHSIZd (ORCPT ); Fri, 19 Aug 2016 04:25:33 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:35868 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754427AbcHSIZa (ORCPT ); Fri, 19 Aug 2016 04:25:30 -0400 From: Alex Shi Cc: Daniel Lezcano , Rasmus Villemoes , Arjan van de Ven , Rik van Riel , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org (open list) Subject: [PATCH 4/4] cpuidle/menu: add per cpu pm_qos_resume_latency consideration Date: Fri, 19 Aug 2016 16:25:14 +0800 Message-Id: <1471595114-1688-4-git-send-email-alex.shi@linaro.org> X-Mailer: git-send-email 2.8.1.101.g72d917a In-Reply-To: <1471595114-1688-1-git-send-email-alex.shi@linaro.org> References: <1471595114-1688-1-git-send-email-alex.shi@linaro.org> To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Kernel or user may have special requirement on cpu response time, like if a interrupt is pinned to a cpu, we don't want the cpu goes too deep sleep. This patch can prevent this thing happen by consider per cpu resume_latency setting in cpu sleep state selection in menu governor. The pm_qos_resume_latency ask device to give reponse in this time. That's similar with cpu cstates' entry_latency + exit_latency. But since most of cpu cstate either has no entry_latency or add it into exit_latency So, we just can restrict this time requirement as states exit_latency. The 0 value of pm_qos_resume_latency is for no limitation according ABI definition. So set the value 1 could get the 0 latency if it's needed. Signed-off-by: Alex Shi To: linux-kernel@vger.kernel.org Cc: Daniel Lezcano Cc: Rasmus Villemoes Cc: Alex Shi Cc: Arjan van de Ven Cc: Rik van Riel Cc: "Rafael J. Wysocki" --- drivers/cpuidle/governors/menu.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index bb58e2a..e354880 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -12,6 +12,7 @@ #include #include +#include #include #include #include @@ -281,17 +282,23 @@ again: static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) { struct menu_device *data = this_cpu_ptr(&menu_devices); + struct device *device = get_cpu_device(dev->cpu); int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); int i; unsigned int interactivity_req; unsigned int expected_interval; unsigned long nr_iowaiters, cpu_load; + int resume_latency = dev_pm_qos_read_value(device); if (data->needs_update) { menu_update(drv, dev); data->needs_update = 0; } + /* resume_latency is 0 means no restriction */ + if (resume_latency && resume_latency < latency_req) + latency_req = resume_latency; + /* Special case when user has set very strict latency requirement */ if (unlikely(latency_req == 0)) return 0; -- 2.8.1.101.g72d917a