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From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Oleg Nesterov <oleg@redhat.com>, Jiri Olsa <jolsa@redhat.com>,
	Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel@vger.kernel.org,
	Stephane Eranian <eranian@google.com>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: [RFC][PATCH 2/9] perf: Clean up ctx reference counting
Date: Sat, 09 Apr 2011 21:17:41 +0200	[thread overview]
Message-ID: <20110409192141.719340481@chello.nl> (raw)
In-Reply-To: 20110409191739.813727025@chello.nl

[-- Attachment #1: perf-cleanup-ctx-ref.patch --]
[-- Type: text/plain, Size: 1228 bytes --]

Small cleanup to how we refcount in find_get_context(), this also
allows us to use put_ctx() to free things instead of using kfree().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
 kernel/perf_event.c |   10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

Index: linux-2.6/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/kernel/perf_event.c
+++ linux-2.6/kernel/perf_event.c
@@ -2831,16 +2831,12 @@ find_get_context(struct pmu *pmu, struct
 		unclone_ctx(ctx);
 		++ctx->pin_count;
 		raw_spin_unlock_irqrestore(&ctx->lock, flags);
-	}
-
-	if (!ctx) {
+	} else {
 		ctx = alloc_perf_context(pmu, task);
 		err = -ENOMEM;
 		if (!ctx)
 			goto errout;
 
-		get_ctx(ctx);
-
 		err = 0;
 		mutex_lock(&task->perf_event_mutex);
 		/*
@@ -2852,14 +2848,14 @@ find_get_context(struct pmu *pmu, struct
 		else if (task->perf_event_ctxp[ctxn])
 			err = -EAGAIN;
 		else {
+			get_ctx(ctx);
 			++ctx->pin_count;
 			rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx);
 		}
 		mutex_unlock(&task->perf_event_mutex);
 
 		if (unlikely(err)) {
-			put_task_struct(task);
-			kfree(ctx);
+			put_ctx(ctx);
 
 			if (err == -EAGAIN)
 				goto retry;



  parent reply	other threads:[~2011-04-09 19:23 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-04-09 19:17 [RFC][PATCH 0/9] perf: Rework event scheduling Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 1/9] perf: Optimize ctx_sched_out Peter Zijlstra
2011-05-28 16:38   ` [tip:perf/core] perf: Optimize ctx_sched_out() tip-bot for Peter Zijlstra
2011-04-09 19:17 ` Peter Zijlstra [this message]
2011-04-11  6:05   ` [RFC][PATCH 2/9] perf: Clean up ctx reference counting Lin Ming
2011-04-11  8:35     ` Peter Zijlstra
2011-05-28 16:39   ` [tip:perf/core] perf: Clean up 'ctx' " tip-bot for Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 3/9] perf: Change event scheduling locking Peter Zijlstra
2011-05-28 16:39   ` [tip:perf/core] perf: Optimize " tip-bot for Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 4/9] perf: Remove task_ctx_sched_in Peter Zijlstra
2011-05-28 16:39   ` [tip:perf/core] perf: Remove task_ctx_sched_in() tip-bot for Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 5/9] perf: Simplify and fix __perf_install_in_context Peter Zijlstra
2011-04-10  8:13   ` Peter Zijlstra
2011-04-11  8:44     ` Lin Ming
2011-04-11  8:50       ` Peter Zijlstra
2011-04-11  8:12   ` Lin Ming
2011-05-28 16:40   ` [tip:perf/core] perf: Simplify and fix __perf_install_in_context() tip-bot for Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 6/9] perf: Change ctx::is_active semantics Peter Zijlstra
2011-05-28 16:40   ` [tip:perf/core] perf: Change and simplify " tip-bot for Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 7/9] perf: Collect the schedule in rules in one function Peter Zijlstra
2011-05-28 16:41   ` [tip:perf/core] perf: Collect the schedule-in " tip-bot for Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 8/9] perf: Change close() semantics for group events Peter Zijlstra
2011-05-28 16:41   ` [tip:perf/core] " tip-bot for Peter Zijlstra
2011-04-09 19:17 ` [RFC][PATCH 9/9] perf: De-schedule a task context when removing the last event Peter Zijlstra
2011-05-28 16:42   ` [tip:perf/core] " tip-bot for Peter Zijlstra

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