From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753786AbcHRJKu (ORCPT ); Thu, 18 Aug 2016 05:10:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37480 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753359AbcHRJKs (ORCPT ); Thu, 18 Aug 2016 05:10:48 -0400 From: Jiri Olsa To: Peter Zijlstra Cc: lkml , Ingo Molnar , Andi Kleen , Alexander Shishkin , Arnaldo Carvalho de Melo Subject: [PATCH] perf/x86: Fix PEBs threshold initialization Date: Thu, 18 Aug 2016 11:09:52 +0200 Message-Id: <1471511392-29875-1-git-send-email-jolsa@kernel.org> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Thu, 18 Aug 2016 09:09:56 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Latest PEBS rework change could skip initialization of the ds->pebs_interrupt_threshold for single event PEBS threshold events. Making sure the PEBS threshold gets always initialized. Fixes: 09e61b4f7849 ("perf/x86/intel: Rework the large PEBS setup code") Signed-off-by: Jiri Olsa --- arch/x86/events/intel/ds.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index 248023f54c87..9fe3db5325d1 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -834,14 +834,24 @@ static inline void pebs_update_threshold(struct cpu_hw_events *cpuc) static void pebs_update_state(bool needed_cb, struct cpu_hw_events *cpuc, struct pmu *pmu) { + /* + * Make sure we get updated with the first PEBs + * event. It'll trigger also during removal, but + * that does not hurt. + */ + bool update = cpuc->n_pebs == 1; + if (needed_cb != pebs_needs_sched_cb(cpuc)) { if (!needed_cb) perf_sched_cb_inc(pmu); else perf_sched_cb_dec(pmu); - pebs_update_threshold(cpuc); + update = true; } + + if (update) + pebs_update_threshold(cpuc); } void intel_pmu_pebs_add(struct perf_event *event) -- 2.7.4