From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756767AbZETRUJ (ORCPT ); Wed, 20 May 2009 13:20:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756552AbZETRT5 (ORCPT ); Wed, 20 May 2009 13:19:57 -0400 Received: from hera.kernel.org ([140.211.167.34]:48381 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756335AbZETRTz (ORCPT ); Wed, 20 May 2009 13:19:55 -0400 Date: Wed, 20 May 2009 17:18:57 GMT From: tip-bot for Peter Zijlstra To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, acme@redhat.com, paulus@samba.org, hpa@zytor.com, mingo@redhat.com, jkacur@redhat.com, a.p.zijlstra@chello.nl, mtosatti@redhat.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, paulus@samba.org, acme@redhat.com, linux-kernel@vger.kernel.org, jkacur@redhat.com, a.p.zijlstra@chello.nl, mtosatti@redhat.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com, mingo@elte.hu In-Reply-To: <20090520102553.298769743@chello.nl> References: <20090520102553.298769743@chello.nl> Subject: [tip:perfcounters/core] perf_counter: Log irq_period changes Message-ID: Git-Commit-ID: 26b119bc811a73bac6ecf95bdf284bf31c7955f0 X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Wed, 20 May 2009 17:18:58 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 26b119bc811a73bac6ecf95bdf284bf31c7955f0 Gitweb: http://git.kernel.org/tip/26b119bc811a73bac6ecf95bdf284bf31c7955f0 Author: Peter Zijlstra AuthorDate: Wed, 20 May 2009 12:21:20 +0200 Committer: Ingo Molnar CommitDate: Wed, 20 May 2009 12:43:33 +0200 perf_counter: Log irq_period changes For the dynamic irq_period code, log whenever we change the period so that analyzing code can normalize the event flow. [ Impact: add new feature to allow more precise profiling ] Signed-off-by: Peter Zijlstra Cc: Paul Mackerras Cc: Corey Ashford Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Thomas Gleixner Cc: Marcelo Tosatti Cc: John Kacur LKML-Reference: <20090520102553.298769743@chello.nl> Signed-off-by: Ingo Molnar --- include/linux/perf_counter.h | 8 ++++++++ kernel/perf_counter.c | 40 +++++++++++++++++++++++++++++++++++++++- 2 files changed, 47 insertions(+), 1 deletions(-) diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index c8c1dfc..f612941 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -258,6 +258,14 @@ enum perf_event_type { PERF_EVENT_COMM = 3, /* + * struct { + * struct perf_event_header header; + * u64 irq_period; + * }; + */ + PERF_EVENT_PERIOD = 4, + + /* * When header.misc & PERF_EVENT_MISC_OVERFLOW the event_type field * will be PERF_RECORD_* * diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 64113e6..db02eb1 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1046,7 +1046,9 @@ int perf_counter_task_enable(void) return 0; } -void perf_adjust_freq(struct perf_counter_context *ctx) +static void perf_log_period(struct perf_counter *counter, u64 period); + +static void perf_adjust_freq(struct perf_counter_context *ctx) { struct perf_counter *counter; u64 irq_period; @@ -1072,6 +1074,8 @@ void perf_adjust_freq(struct perf_counter_context *ctx) if (!irq_period) irq_period = 1; + perf_log_period(counter, irq_period); + counter->hw.irq_period = irq_period; counter->hw.interrupts = 0; } @@ -2407,6 +2411,40 @@ void perf_counter_munmap(unsigned long addr, unsigned long len, } /* + * + */ + +static void perf_log_period(struct perf_counter *counter, u64 period) +{ + struct perf_output_handle handle; + int ret; + + struct { + struct perf_event_header header; + u64 time; + u64 period; + } freq_event = { + .header = { + .type = PERF_EVENT_PERIOD, + .misc = 0, + .size = sizeof(freq_event), + }, + .time = sched_clock(), + .period = period, + }; + + if (counter->hw.irq_period == period) + return; + + ret = perf_output_begin(&handle, counter, sizeof(freq_event), 0, 0); + if (ret) + return; + + perf_output_put(&handle, freq_event); + perf_output_end(&handle); +} + +/* * Generic counter overflow handling. */