From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756089Ab3HLKRT (ORCPT ); Mon, 12 Aug 2013 06:17:19 -0400 Received: from terminus.zytor.com ([198.137.202.10]:47659 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756011Ab3HLKRM (ORCPT ); Mon, 12 Aug 2013 06:17:12 -0400 Date: Mon, 12 Aug 2013 03:16:32 -0700 From: tip-bot for Jiri Olsa Message-ID: Cc: acme@redhat.com, linux-kernel@vger.kernel.org, paulus@samba.org, hpa@zytor.com, mingo@kernel.org, a.p.zijlstra@chello.nl, namhyung@kernel.org, jolsa@redhat.com, fweisbec@gmail.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com Reply-To: mingo@kernel.org, hpa@zytor.com, paulus@samba.org, linux-kernel@vger.kernel.org, acme@redhat.com, a.p.zijlstra@chello.nl, namhyung@kernel.org, jolsa@redhat.com, fweisbec@gmail.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf: Add PERF_EVENT_IOC_ID ioctl to return event ID Git-Commit-ID: cf4957f17f2a89984915ea808876d9c82225b862 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Mon, 12 Aug 2013 03:16:40 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: cf4957f17f2a89984915ea808876d9c82225b862 Gitweb: http://git.kernel.org/tip/cf4957f17f2a89984915ea808876d9c82225b862 Author: Jiri Olsa AuthorDate: Wed, 24 Oct 2012 13:37:58 +0200 Committer: Arnaldo Carvalho de Melo CommitDate: Wed, 7 Aug 2013 17:35:19 -0300 perf: Add PERF_EVENT_IOC_ID ioctl to return event ID The only way to get the event ID is by reading the event fd, followed by parsing the ID value out of the returned data. While this is ok for current read format used by perf tool, it is not ok when we use PERF_FORMAT_GROUP format. With this format the data are returned for the whole group and there's no way to find out what ID belongs to our fd (if we are not group leader event). Adding a simple ioctl that returns event primary ID for given fd. Signed-off-by: Jiri Olsa Acked-by: Namhyung Kim Acked-by: Peter Zijlstra Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-v1bn5cto707jn0bon34afqr1@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- include/uapi/linux/perf_event.h | 1 + kernel/events/core.c | 9 +++++++++ 2 files changed, 10 insertions(+) diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index efef1d3..62c25a2 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -321,6 +321,7 @@ struct perf_event_attr { #define PERF_EVENT_IOC_PERIOD _IOW('$', 4, __u64) #define PERF_EVENT_IOC_SET_OUTPUT _IO ('$', 5) #define PERF_EVENT_IOC_SET_FILTER _IOW('$', 6, char *) +#define PERF_EVENT_IOC_ID _IOR('$', 7, u64 *) enum perf_event_ioc_flags { PERF_IOC_FLAG_GROUP = 1U << 0, diff --git a/kernel/events/core.c b/kernel/events/core.c index 916cf1f..5200b60 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3568,6 +3568,15 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case PERF_EVENT_IOC_PERIOD: return perf_event_period(event, (u64 __user *)arg); + case PERF_EVENT_IOC_ID: + { + u64 id = primary_event_id(event); + + if (copy_to_user((void __user *)arg, &id, sizeof(id))) + return -EFAULT; + return 0; + } + case PERF_EVENT_IOC_SET_OUTPUT: { int ret;