From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759487Ab3KMPSi (ORCPT ); Wed, 13 Nov 2013 10:18:38 -0500 Received: from merlin.infradead.org ([205.233.59.134]:60234 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754062Ab3KMPSf (ORCPT ); Wed, 13 Nov 2013 10:18:35 -0500 Date: Wed, 13 Nov 2013 16:18:22 +0100 From: Peter Zijlstra To: Mischa Jonker Cc: linux-kernel@vger.kernel.org, Vineet Gupta Subject: Re: [PATCH] ARC: perf: ARC 700 PMU doesn't support sampling events Message-ID: <20131113151822.GO21461@twins.programming.kicks-ass.net> References: <1384355166-21409-1-git-send-email-mjonker@synopsys.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1384355166-21409-1-git-send-email-mjonker@synopsys.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 13, 2013 at 04:06:06PM +0100, Mischa Jonker wrote: > The ARC 700 does not have an interrupt associated with it, and as > such it cannot trigger when a counter overflows. As the counters are > 48 bit, it will usually take at least 100 days before a counter > overflows, so for mere counting of events, there is no problem. > Sampling is not supported though. Acked-by: Peter Zijlstra > Cc: Vineet Gupta > Signed-off-by: Mischa Jonker > --- > arch/arc/kernel/perf_event.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c > index 759e5f3..e46d81f 100644 > --- a/arch/arc/kernel/perf_event.c > +++ b/arch/arc/kernel/perf_event.c > @@ -99,6 +99,10 @@ static int arc_pmu_event_init(struct perf_event *event) > struct hw_perf_event *hwc = &event->hw; > int ret; > > + /* ARC 700 PMU does not support sampling events */ > + if (is_sampling_event(event)) > + return -ENOENT; > + > switch (event->attr.type) { > case PERF_TYPE_HARDWARE: > if (event->attr.config >= PERF_COUNT_HW_MAX) > -- > 1.7.9.5 >