Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753138AbcDBJcp (ORCPT ); Sat, 2 Apr 2016 05:32:45 -0400 Received: from ud10.udmedia.de ([194.117.254.50]:44358 "EHLO mail.ud10.udmedia.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752618AbcDBJcn (ORCPT ); Sat, 2 Apr 2016 05:32:43 -0400 Date: Sat, 2 Apr 2016 11:32:39 +0200 From: Markus Trippelsdorf To: linux-kernel@vger.kernel.org Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin Subject: "perf: interrupt took too long" messages even with perf_cpu_time_max_percent==0 Message-ID: <20160402093239.GA305@x4> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 618 Lines: 14 Current git kernel sometimes shows: perf: interrupt took too long (71 > 52), lowering kernel.perf_event_max_sample_rate to 300 perf: interrupt took too long (103 > 88), lowering kernel.perf_event_max_sample_rate to 300 perf: interrupt took too long (130 > 128), lowering kernel.perf_event_max_sample_rate to 300 perf: interrupt took too long (175 > 162), lowering kernel.perf_event_max_sample_rate to 300 perf: interrupt took too long (219 > 218), lowering kernel.perf_event_max_sample_rate to 300 ... when running e.g. "perf top" even when /proc/sys/kernel/perf_cpu_time_max_percent is set to 0. -- Markus