From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752581AbdBJIhf (ORCPT ); Fri, 10 Feb 2017 03:37:35 -0500 Received: from terminus.zytor.com ([65.50.211.136]:53368 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752075AbdBJIhP (ORCPT ); Fri, 10 Feb 2017 03:37:15 -0500 Date: Fri, 10 Feb 2017 00:34:26 -0800 From: tip-bot for Alexander Shishkin Message-ID: Cc: jolsa@redhat.com, eranian@google.com, vincent.weaver@maine.edu, mark.rutland@arm.com, linux-kernel@vger.kernel.org, acme@redhat.com, will.deacon@arm.com, mingo@kernel.org, peterz@infradead.org, tglx@linutronix.de, acme@infradead.org, hpa@zytor.com, mathieu.poirier@linaro.org, alexander.shishkin@linux.intel.com, torvalds@linux-foundation.org Reply-To: acme@infradead.org, hpa@zytor.com, peterz@infradead.org, tglx@linutronix.de, mingo@kernel.org, torvalds@linux-foundation.org, alexander.shishkin@linux.intel.com, mathieu.poirier@linaro.org, mark.rutland@arm.com, eranian@google.com, vincent.weaver@maine.edu, jolsa@redhat.com, will.deacon@arm.com, acme@redhat.com, linux-kernel@vger.kernel.org In-Reply-To: <20170126094057.13805-4-alexander.shishkin@linux.intel.com> References: <20170126094057.13805-4-alexander.shishkin@linux.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf/core: Allow kernel filters on CPU events Git-Commit-ID: 6ce77bfd6cedbff61eabf8837dc0901bb671cc86 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 6ce77bfd6cedbff61eabf8837dc0901bb671cc86 Gitweb: http://git.kernel.org/tip/6ce77bfd6cedbff61eabf8837dc0901bb671cc86 Author: Alexander Shishkin AuthorDate: Thu, 26 Jan 2017 11:40:57 +0200 Committer: Ingo Molnar CommitDate: Fri, 10 Feb 2017 09:08:09 +0100 perf/core: Allow kernel filters on CPU events While supporting file-based address filters for CPU events requires some extra context switch handling, kernel address filters are easy, since the kernel mapping is preserved across address spaces. It is also useful as it permits tracing scheduling paths of the kernel. This patch allows setting up kernel filters for CPU events. Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Mark Rutland Cc: Mathieu Poirier Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: Will Deacon Cc: vince@deater.net Link: http://lkml.kernel.org/r/20170126094057.13805-4-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- include/linux/perf_event.h | 2 ++ kernel/events/core.c | 42 ++++++++++++++++++++++++++++-------------- 2 files changed, 30 insertions(+), 14 deletions(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 5c58e93..000fdb2 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -482,6 +482,7 @@ struct perf_addr_filter { * @list: list of filters for this event * @lock: spinlock that serializes accesses to the @list and event's * (and its children's) filter generations. + * @nr_file_filters: number of file-based filters * * A child event will use parent's @list (and therefore @lock), so they are * bundled together; see perf_event_addr_filters(). @@ -489,6 +490,7 @@ struct perf_addr_filter { struct perf_addr_filters_head { struct list_head list; raw_spinlock_t lock; + unsigned int nr_file_filters; }; /** diff --git a/kernel/events/core.c b/kernel/events/core.c index 1730995..a866424 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8090,6 +8090,9 @@ static void perf_event_addr_filters_apply(struct perf_event *event) if (task == TASK_TOMBSTONE) return; + if (!ifh->nr_file_filters) + return; + mm = get_task_mm(event->ctx->task); if (!mm) goto restart; @@ -8268,6 +8271,18 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr, if (!filename) goto fail; + /* + * For now, we only support file-based filters + * in per-task events; doing so for CPU-wide + * events requires additional context switching + * trickery, since same object code will be + * mapped at different virtual addresses in + * different processes. + */ + ret = -EOPNOTSUPP; + if (!event->ctx->task) + goto fail_free_name; + /* look up the path and grab its inode */ ret = kern_path(filename, LOOKUP_FOLLOW, &path); if (ret) @@ -8283,6 +8298,8 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr, !S_ISREG(filter->inode->i_mode)) /* free_filters_list() will iput() */ goto fail; + + event->addr_filters.nr_file_filters++; } /* ready to consume more filters */ @@ -8322,24 +8339,13 @@ perf_event_set_addr_filter(struct perf_event *event, char *filter_str) if (WARN_ON_ONCE(event->parent)) return -EINVAL; - /* - * For now, we only support filtering in per-task events; doing so - * for CPU-wide events requires additional context switching trickery, - * since same object code will be mapped at different virtual - * addresses in different processes. - */ - if (!event->ctx->task) - return -EOPNOTSUPP; - ret = perf_event_parse_addr_filter(event, filter_str, &filters); if (ret) - return ret; + goto fail_clear_files; ret = event->pmu->addr_filters_validate(&filters); - if (ret) { - free_filters_list(&filters); - return ret; - } + if (ret) + goto fail_free_filters; /* remove existing filters, if any */ perf_addr_filters_splice(event, &filters); @@ -8348,6 +8354,14 @@ perf_event_set_addr_filter(struct perf_event *event, char *filter_str) perf_event_for_each_child(event, perf_event_addr_filters_apply); return ret; + +fail_free_filters: + free_filters_list(&filters); + +fail_clear_files: + event->addr_filters.nr_file_filters = 0; + + return ret; } static int perf_event_set_filter(struct perf_event *event, void __user *arg)