From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org by pdx-caf-mail.web.codeaurora.org (Dovecot) with LMTP id u0azK/xcGFvkJAAAmS7hNA ; Wed, 06 Jun 2018 22:16:17 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id E53866089E; Wed, 6 Jun 2018 22:16:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by smtp.codeaurora.org (Postfix) with ESMTP id 6CA3A605BD; Wed, 6 Jun 2018 22:16:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 6CA3A605BD Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752997AbeFFWQO (ORCPT + 25 others); Wed, 6 Jun 2018 18:16:14 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:41862 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752854AbeFFWPn (ORCPT ); Wed, 6 Jun 2018 18:15:43 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0F4A3407574B; Wed, 6 Jun 2018 22:15:42 +0000 (UTC) Received: from krava.redhat.com (ovpn-204-89.brq.redhat.com [10.40.204.89]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1AABF2026DEF; Wed, 6 Jun 2018 22:15:39 +0000 (UTC) From: Jiri Olsa To: Arnaldo Carvalho de Melo , Peter Zijlstra Cc: lkml , Ingo Molnar , Namhyung Kim , David Ahern , Alexander Shishkin , Stephane Eranian , Milian Wolff , Andi Kleen , Frederic Weisbecker Subject: [PATCH 09/10] perf/cputime: Don't stop idle tick if there's live cputime event Date: Thu, 7 Jun 2018 00:15:12 +0200 Message-Id: <20180606221513.11302-10-jolsa@kernel.org> In-Reply-To: <20180606221513.11302-1-jolsa@kernel.org> References: <20180606221513.11302-1-jolsa@kernel.org> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 06 Jun 2018 22:15:42 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 06 Jun 2018 22:15:42 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jolsa@kernel.org' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Disable stopping of the idle tick when having live cputime event. When the tick is disabled, the idle counts are out of date until next tick/update and perf cputime PMU provides misleading counts. Signed-off-by: Jiri Olsa --- include/linux/perf_event.h | 1 + kernel/events/cputime.c | 13 +++++++++++++ kernel/time/tick-sched.c | 4 ++++ 3 files changed, 18 insertions(+) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index aa9eaab370be..ba61d2f9602a 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1407,4 +1407,5 @@ int perf_event_exit_cpu(unsigned int cpu); #define perf_event_exit_cpu NULL #endif +bool has_cputime_event(int cpu); #endif /* _LINUX_PERF_EVENT_H */ diff --git a/kernel/events/cputime.c b/kernel/events/cputime.c index efad24543f13..32d3cde0047e 100644 --- a/kernel/events/cputime.c +++ b/kernel/events/cputime.c @@ -1,6 +1,7 @@ #include #include #include +#include enum perf_cputime_id { PERF_CPUTIME_USER, @@ -16,6 +17,13 @@ enum perf_cputime_id { PERF_CPUTIME_MAX, }; +static DEFINE_PER_CPU(int, has_cputime); + +bool has_cputime_event(int cpu) +{ + return per_cpu(has_cputime, cpu) != 0; +} + static enum cpu_usage_stat map[PERF_CPUTIME_MAX] = { [PERF_CPUTIME_USER] = CPUTIME_USER, [PERF_CPUTIME_NICE] = CPUTIME_NICE, @@ -143,12 +151,17 @@ static int cputime_event_add(struct perf_event *event, int flags) if (flags & PERF_EF_START) cputime_event_start(event, flags); + if (event->hw.config == PERF_CPUTIME_IDLE) + tick_nohz_idle_restart_tick(); + + this_cpu_inc(has_cputime); return 0; } static void cputime_event_del(struct perf_event *event, int flags) { cputime_event_stop(event, PERF_EF_UPDATE); + this_cpu_dec(has_cputime); } static void perf_cputime_read(struct perf_event *event) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index da9455a6b42b..1c105bc2a92e 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -28,6 +28,7 @@ #include #include #include +#include #include @@ -912,6 +913,9 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) return false; } + if (has_cputime_event(cpu)) + return false; + return true; } -- 2.13.6