From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758064AbZEEQTv (ORCPT ); Tue, 5 May 2009 12:19:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755510AbZEEQSM (ORCPT ); Tue, 5 May 2009 12:18:12 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:50001 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754324AbZEEQSJ (ORCPT ); Tue, 5 May 2009 12:18:09 -0400 Message-Id: <20090505155437.331556171@chello.nl> References: <20090505155020.309162852@chello.nl> User-Agent: quilt/0.46-1 Date: Tue, 05 May 2009 17:50:26 +0200 From: Peter Zijlstra To: Ingo Molnar Cc: Paul Mackerras , Corey Ashford , linux-kernel@vger.kernel.org, Peter Zijlstra Subject: [PATCH 6/7] perf_counter: inheritable sample counters Content-Disposition: inline; filename=perf_counter-inherit.patch X-Bad-Reply: References but no 'Re:' in Subject. Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Redirect the output to the parent counter and put in some sanity checks. Signed-off-by: Peter Zijlstra --- kernel/perf_counter.c | 32 ++++++++++++++++++++++++++++++-- 1 file changed, 30 insertions(+), 2 deletions(-) Index: linux-2.6/kernel/perf_counter.c =================================================================== --- linux-2.6.orig/kernel/perf_counter.c +++ linux-2.6/kernel/perf_counter.c @@ -738,10 +738,18 @@ static void perf_counter_enable(struct p spin_unlock_irq(&ctx->lock); } -static void perf_counter_refresh(struct perf_counter *counter, int refresh) +static int perf_counter_refresh(struct perf_counter *counter, int refresh) { + /* + * not supported on inherited counters + */ + if (counter->hw_event.inherit) + return -EINVAL; + atomic_add(refresh, &counter->event_limit); perf_counter_enable(counter); + + return 0; } /* @@ -1307,7 +1315,7 @@ static long perf_ioctl(struct file *file perf_counter_disable_family(counter); break; case PERF_COUNTER_IOC_REFRESH: - perf_counter_refresh(counter, arg); + err = perf_counter_refresh(counter, arg); break; case PERF_COUNTER_IOC_RESET: perf_counter_reset(counter); @@ -1814,6 +1822,12 @@ static int perf_output_begin(struct perf struct perf_mmap_data *data; unsigned int offset, head; + /* + * For inherited counters we send all the output towards the parent. + */ + if (counter->parent) + counter = counter->parent; + rcu_read_lock(); data = rcu_dereference(counter->data); if (!data) @@ -1995,6 +2009,9 @@ static void perf_counter_output(struct p if (record_type & PERF_RECORD_ADDR) perf_output_put(&handle, addr); + /* + * XXX PERF_RECORD_GROUP vs inherited counters seems difficult. + */ if (record_type & PERF_RECORD_GROUP) { struct perf_counter *leader, *sub; u64 nr = counter->nr_siblings; @@ -2281,6 +2298,11 @@ int perf_counter_overflow(struct perf_co int events = atomic_read(&counter->event_limit); int ret = 0; + /* + * XXX event_limit might not quite work as expected on inherited + * counters + */ + counter->pending_kill = POLL_IN; if (events && atomic_dec_and_test(&counter->event_limit)) { ret = 1; @@ -2801,6 +2823,12 @@ perf_counter_alloc(struct perf_counter_h pmu = NULL; + /* + * we currently do not support PERF_RECORD_GROUP on inherited counters + */ + if (hw_event->inherit && (hw_event->record_type & PERF_RECORD_GROUP)) + goto done; + if (perf_event_raw(hw_event)) { pmu = hw_perf_counter_init(counter); goto done; --