From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933095Ab1LFJqN (ORCPT ); Tue, 6 Dec 2011 04:46:13 -0500 Received: from terminus.zytor.com ([198.137.202.10]:34827 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932974Ab1LFJqM (ORCPT ); Tue, 6 Dec 2011 04:46:12 -0500 Date: Tue, 6 Dec 2011 01:45:49 -0800 From: tip-bot for Peter Zijlstra Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@elte.hu To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf, x86: Prefer fixed-purpose counters when scheduling Git-Commit-ID: 4defea8559bc0f97a899d94c8d19d3b8bb802bc4 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (terminus.zytor.com [127.0.0.1]); Tue, 06 Dec 2011 01:45:54 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 4defea8559bc0f97a899d94c8d19d3b8bb802bc4 Gitweb: http://git.kernel.org/tip/4defea8559bc0f97a899d94c8d19d3b8bb802bc4 Author: Peter Zijlstra AuthorDate: Thu, 10 Nov 2011 15:15:42 +0100 Committer: Ingo Molnar CommitDate: Tue, 6 Dec 2011 08:33:58 +0100 perf, x86: Prefer fixed-purpose counters when scheduling This avoids a scheduling failure for cases like: cycles, cycles, instructions, instructions (on Core2) Which would end up being programmed like: PMC0, PMC1, FP-instructions, fail Because all events will have the same weight. Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-8tnwb92asqj7xajqqoty4gel@git.kernel.org Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event.c | 19 ++++++++++++++----- 1 files changed, 14 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index fa6fdec..66f8ba9 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -574,16 +574,25 @@ static bool __perf_sched_find_counter(struct perf_sched *sched) c = sched->constraints[sched->state.event]; + /* Prefer fixed purpose counters */ + if (x86_pmu.num_counters_fixed) { + idx = X86_PMC_IDX_FIXED; + for_each_set_bit_cont(idx, c->idxmsk, X86_PMC_IDX_MAX) { + if (!__test_and_set_bit(idx, sched->state.used)) + goto done; + } + } /* Grab the first unused counter starting with idx */ idx = sched->state.counter; - for_each_set_bit_cont(idx, c->idxmsk, X86_PMC_IDX_MAX) { + for_each_set_bit_cont(idx, c->idxmsk, X86_PMC_IDX_FIXED) { if (!__test_and_set_bit(idx, sched->state.used)) - break; + goto done; } - sched->state.counter = idx; - if (idx >= X86_PMC_IDX_MAX) - return false; + return false; + +done: + sched->state.counter = idx; if (c->overlap) perf_sched_save_state(sched);