From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752039AbaHMIXF (ORCPT ); Wed, 13 Aug 2014 04:23:05 -0400 Received: from terminus.zytor.com ([198.137.202.10]:51965 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751976AbaHMIXA (ORCPT ); Wed, 13 Aug 2014 04:23:00 -0400 Date: Wed, 13 Aug 2014 01:21:49 -0700 From: tip-bot for Jiri Olsa Message-ID: Cc: linux-kernel@vger.kernel.org, paulus@samba.org, hpa@zytor.com, mingo@kernel.org, jolsa@kernel.org, torvalds@linux-foundation.org, peterz@infradead.org, mark.rutland@arm.com, acme@kernel.org, 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, jolsa@kernel.org, torvalds@linux-foundation.org, peterz@infradead.org, acme@kernel.org, mark.rutland@arm.com, fweisbec@gmail.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com In-Reply-To: <1406896382-18404-3-git-send-email-jolsa@kernel.org> References: <1406896382-18404-3-git-send-email-jolsa@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf: Set owner pointer for kernel events Git-Commit-ID: f86977620ee4635f26befcf436700493a38ce002 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: f86977620ee4635f26befcf436700493a38ce002 Gitweb: http://git.kernel.org/tip/f86977620ee4635f26befcf436700493a38ce002 Author: Jiri Olsa AuthorDate: Fri, 1 Aug 2014 14:33:01 +0200 Committer: Ingo Molnar CommitDate: Wed, 13 Aug 2014 07:51:03 +0200 perf: Set owner pointer for kernel events Adding fake EVENT_OWNER_KERNEL owner pointer value for kernel perf events, so we could distinguish it from user events, which needs special care in following patch. Signed-off-by: Jiri Olsa Signed-off-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Mark Rutland Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Mark Rutland Cc: Linus Torvalds Link: http://lkml.kernel.org/r/1406896382-18404-3-git-send-email-jolsa@kernel.org Signed-off-by: Ingo Molnar --- kernel/events/core.c | 32 ++++++++++++++++++++++++++------ 1 file changed, 26 insertions(+), 6 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 1cf24b3..bbb3ca2 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -119,6 +119,13 @@ static int cpu_function_call(int cpu, int (*func) (void *info), void *info) return data.ret; } +#define EVENT_OWNER_KERNEL ((void *) -1) + +static bool is_kernel_event(struct perf_event *event) +{ + return event->owner == EVENT_OWNER_KERNEL; +} + #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ PERF_FLAG_FD_OUTPUT |\ PERF_FLAG_PID_CGROUP |\ @@ -3312,16 +3319,12 @@ static void free_event(struct perf_event *event) } /* - * Called when the last reference to the file is gone. + * Remove user event from the owner task. */ -static void put_event(struct perf_event *event) +static void perf_remove_from_owner(struct perf_event *event) { - struct perf_event_context *ctx = event->ctx; struct task_struct *owner; - if (!atomic_long_dec_and_test(&event->refcount)) - return; - rcu_read_lock(); owner = ACCESS_ONCE(event->owner); /* @@ -3354,6 +3357,20 @@ static void put_event(struct perf_event *event) mutex_unlock(&owner->perf_event_mutex); put_task_struct(owner); } +} + +/* + * Called when the last reference to the file is gone. + */ +static void put_event(struct perf_event *event) +{ + struct perf_event_context *ctx = event->ctx; + + if (!atomic_long_dec_and_test(&event->refcount)) + return; + + if (!is_kernel_event(event)) + perf_remove_from_owner(event); WARN_ON_ONCE(ctx->parent_ctx); /* @@ -7366,6 +7383,9 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, goto err; } + /* Mark owner so we could distinguish it from user events. */ + event->owner = EVENT_OWNER_KERNEL; + account_event(event); ctx = find_get_context(event->pmu, task, cpu);