[PATCH 0/2] perf: Fix/factor auxiliary events

[PATCH 0/2] perf: Fix/factor auxiliary events

[Jiri Olsa]

hi,
sending fix for issue caused by using smp_processor_id()
in preemptible path discussed in here:
http://marc.info/?l=linux-kernel&m=136733569907888&w=2

I also noticed there's a space for some code factoring
saving some .text size and centralizing auxiliary
events notification.

Changes could be reached in here:
git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
perf/aux4

thanks,
jirka

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
---
Jiri Olsa (2):
      perf: Fix EXIT event notification
      perf: Factor auxiliary events notification

 kernel/events/core.c | 240 +++++++++++++++++++++++++++++++++++++++++---------------------------------------------------------------------
 1 file changed, 89 insertions(+), 151 deletions(-)

[PATCH 1/2] perf: Fix EXIT event notification

[Jiri Olsa]

The perf_event_task_ctx needs to be called with preemption
disabled, since it's checking for currently scheduled cpu
against event cpu.

We disable preemption for task related perf event context
if there's one defined, leaving up to the chance which cpu
it gets scheduled in.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
---
 kernel/events/core.c | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 6b41c18..38b68a0 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4474,7 +4474,7 @@ static void perf_event_task_ctx(struct perf_event_context *ctx,
 static void perf_event_task_event(struct perf_task_event *task_event)
 {
 	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
+	struct perf_event_context *ctx, *task_ctx = task_event->task_ctx;
 	struct pmu *pmu;
 	int ctxn;
 
@@ -4485,20 +4485,22 @@ static void perf_event_task_event(struct perf_task_event *task_event)
 			goto next;
 		perf_event_task_ctx(&cpuctx->ctx, task_event);
 
-		ctx = task_event->task_ctx;
-		if (!ctx) {
-			ctxn = pmu->task_ctx_nr;
-			if (ctxn < 0)
-				goto next;
-			ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-			if (ctx)
-				perf_event_task_ctx(ctx, task_event);
-		}
+		if (task_ctx)
+			goto next;
+		ctxn = pmu->task_ctx_nr;
+		if (ctxn < 0)
+			goto next;
+		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+		if (ctx)
+			perf_event_task_ctx(ctx, task_event);
 next:
 		put_cpu_ptr(pmu->pmu_cpu_context);
 	}
-	if (task_event->task_ctx)
-		perf_event_task_ctx(task_event->task_ctx, task_event);
+	if (task_ctx) {
+		preempt_disable();
+		perf_event_task_ctx(task_ctx, task_event);
+		preempt_enable();
+	}
 
 	rcu_read_unlock();
 }
-- 
1.7.11.7

[tip:perf/urgent] perf: Fix EXIT event notification

[tip-bot for Jiri Olsa]

Commit-ID:  524eff183f51d080a83b348d0ea97c08b3607b9a
Gitweb:     http://git.kernel.org/tip/524eff183f51d080a83b348d0ea97c08b3607b9a
Author:     Jiri Olsa <jolsa@redhat.com>
AuthorDate: Mon, 6 May 2013 18:27:17 +0200
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 7 May 2013 13:17:28 +0200

perf: Fix EXIT event notification

The perf_event_task_ctx() function needs to be called with
preemption disabled, since it's checking for currently
scheduled cpu against event cpu.

We disable preemption for task related perf event context
if there's one defined, leaving up to the chance which cpu
it gets scheduled in.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/1367857638-27631-2-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/events/core.c | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 6b41c18..38b68a0 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4474,7 +4474,7 @@ static void perf_event_task_ctx(struct perf_event_context *ctx,
 static void perf_event_task_event(struct perf_task_event *task_event)
 {
 	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
+	struct perf_event_context *ctx, *task_ctx = task_event->task_ctx;
 	struct pmu *pmu;
 	int ctxn;
 
@@ -4485,20 +4485,22 @@ static void perf_event_task_event(struct perf_task_event *task_event)
 			goto next;
 		perf_event_task_ctx(&cpuctx->ctx, task_event);
 
-		ctx = task_event->task_ctx;
-		if (!ctx) {
-			ctxn = pmu->task_ctx_nr;
-			if (ctxn < 0)
-				goto next;
-			ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-			if (ctx)
-				perf_event_task_ctx(ctx, task_event);
-		}
+		if (task_ctx)
+			goto next;
+		ctxn = pmu->task_ctx_nr;
+		if (ctxn < 0)
+			goto next;
+		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+		if (ctx)
+			perf_event_task_ctx(ctx, task_event);
 next:
 		put_cpu_ptr(pmu->pmu_cpu_context);
 	}
-	if (task_event->task_ctx)
-		perf_event_task_ctx(task_event->task_ctx, task_event);
+	if (task_ctx) {
+		preempt_disable();
+		perf_event_task_ctx(task_ctx, task_event);
+		preempt_enable();
+	}
 
 	rcu_read_unlock();
 }

[PATCH 2/2] perf: Factor auxiliary events notification

[Jiri Olsa]

Adding perf_event_aux function to send out all types of
auxiliary events - mmap, task, comm events. For each type
there's match and output functions defined and used as
callbacks during perf_event_aux processing.

This way we can centralize the pmu/context iterating and
event matching logic. Also since lot of the code was
duplicated, this patch reduces the .text size about 2kB
on my setup:

  snipped output from 'objdump -x kernel/events/core.o'

  before:
  Idx Name          Size
    0 .text         0000d313

  after:
  Idx Name          Size
    0 .text         0000cad3

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
---
 kernel/events/core.c | 242 +++++++++++++++++++--------------------------------
 1 file changed, 89 insertions(+), 153 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 38b68a0..9dc297f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4394,6 +4394,64 @@ perf_event_read_event(struct perf_event *event,
 	perf_output_end(&handle);
 }
 
+typedef int  (perf_event_aux_match_cb)(struct perf_event *event, void *data);
+typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);
+
+static void
+perf_event_aux_ctx(struct perf_event_context *ctx,
+		   perf_event_aux_match_cb match,
+		   perf_event_aux_output_cb output,
+		   void *data)
+{
+	struct perf_event *event;
+
+	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+		if (event->state < PERF_EVENT_STATE_INACTIVE)
+			continue;
+		if (!event_filter_match(event))
+			continue;
+		if (match(event, data))
+			output(event, data);
+	}
+}
+
+static void
+perf_event_aux(perf_event_aux_match_cb match,
+	       perf_event_aux_output_cb output,
+	       void *data,
+	       struct perf_event_context *task_ctx)
+{
+	struct perf_cpu_context *cpuctx;
+	struct perf_event_context *ctx;
+	struct pmu *pmu;
+	int ctxn;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(pmu, &pmus, entry) {
+		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
+		if (cpuctx->unique_pmu != pmu)
+			goto next;
+		perf_event_aux_ctx(&cpuctx->ctx, match, output, data);
+		if (task_ctx)
+			goto next;
+		ctxn = pmu->task_ctx_nr;
+		if (ctxn < 0)
+			goto next;
+		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+		if (ctx)
+			perf_event_aux_ctx(ctx, match, output, data);
+next:
+		put_cpu_ptr(pmu->pmu_cpu_context);
+	}
+
+	if (task_ctx) {
+		preempt_disable();
+		perf_event_aux_ctx(task_ctx, match, output, data);
+		preempt_enable();
+	}
+	rcu_read_unlock();
+}
+
 /*
  * task tracking -- fork/exit
  *
@@ -4416,8 +4474,9 @@ struct perf_task_event {
 };
 
 static void perf_event_task_output(struct perf_event *event,
-				     struct perf_task_event *task_event)
+				   void *data)
 {
+	struct perf_task_event *task_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data	sample;
 	struct task_struct *task = task_event->task;
@@ -4445,64 +4504,11 @@ out:
 	task_event->event_id.header.size = size;
 }
 
-static int perf_event_task_match(struct perf_event *event)
-{
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if (event->attr.comm || event->attr.mmap ||
-	    event->attr.mmap_data || event->attr.task)
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_task_ctx(struct perf_event_context *ctx,
-				  struct perf_task_event *task_event)
-{
-	struct perf_event *event;
-
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_task_match(event))
-			perf_event_task_output(event, task_event);
-	}
-}
-
-static void perf_event_task_event(struct perf_task_event *task_event)
+static int perf_event_task_match(struct perf_event *event,
+				 void *data __maybe_unused)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx, *task_ctx = task_event->task_ctx;
-	struct pmu *pmu;
-	int ctxn;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_task_ctx(&cpuctx->ctx, task_event);
-
-		if (task_ctx)
-			goto next;
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx)
-			perf_event_task_ctx(ctx, task_event);
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	if (task_ctx) {
-		preempt_disable();
-		perf_event_task_ctx(task_ctx, task_event);
-		preempt_enable();
-	}
-
-	rcu_read_unlock();
+	return event->attr.comm || event->attr.mmap ||
+	       event->attr.mmap_data || event->attr.task;
 }
 
 static void perf_event_task(struct task_struct *task,
@@ -4533,7 +4539,10 @@ static void perf_event_task(struct task_struct *task,
 		},
 	};
 
-	perf_event_task_event(&task_event);
+	perf_event_aux(perf_event_task_match,
+		       perf_event_task_output,
+		       &task_event,
+		       task_ctx);
 }
 
 void perf_event_fork(struct task_struct *task)
@@ -4559,8 +4568,9 @@ struct perf_comm_event {
 };
 
 static void perf_event_comm_output(struct perf_event *event,
-				     struct perf_comm_event *comm_event)
+				   void *data)
 {
+	struct perf_comm_event *comm_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data sample;
 	int size = comm_event->event_id.header.size;
@@ -4587,39 +4597,16 @@ out:
 	comm_event->event_id.header.size = size;
 }
 
-static int perf_event_comm_match(struct perf_event *event)
-{
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if (event->attr.comm)
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_comm_ctx(struct perf_event_context *ctx,
-				  struct perf_comm_event *comm_event)
+static int perf_event_comm_match(struct perf_event *event,
+				 void *data __maybe_unused)
 {
-	struct perf_event *event;
-
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_comm_match(event))
-			perf_event_comm_output(event, comm_event);
-	}
+	return event->attr.comm;
 }
 
 static void perf_event_comm_event(struct perf_comm_event *comm_event)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
 	char comm[TASK_COMM_LEN];
 	unsigned int size;
-	struct pmu *pmu;
-	int ctxn;
 
 	memset(comm, 0, sizeof(comm));
 	strlcpy(comm, comm_event->task->comm, sizeof(comm));
@@ -4629,24 +4616,11 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	comm_event->comm_size = size;
 
 	comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_comm_ctx(&cpuctx->ctx, comm_event);
 
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx)
-			perf_event_comm_ctx(ctx, comm_event);
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	rcu_read_unlock();
+	perf_event_aux(perf_event_comm_match,
+		       perf_event_comm_output,
+		       comm_event,
+		       NULL);
 }
 
 void perf_event_comm(struct task_struct *task)
@@ -4708,8 +4682,9 @@ struct perf_mmap_event {
 };
 
 static void perf_event_mmap_output(struct perf_event *event,
-				     struct perf_mmap_event *mmap_event)
+				   void *data)
 {
+	struct perf_mmap_event *mmap_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data sample;
 	int size = mmap_event->event_id.header.size;
@@ -4736,46 +4711,24 @@ out:
 }
 
 static int perf_event_mmap_match(struct perf_event *event,
-				   struct perf_mmap_event *mmap_event,
-				   int executable)
+				 void *data)
 {
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if ((!executable && event->attr.mmap_data) ||
-	    (executable && event->attr.mmap))
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_mmap_ctx(struct perf_event_context *ctx,
-				  struct perf_mmap_event *mmap_event,
-				  int executable)
-{
-	struct perf_event *event;
+	struct perf_mmap_event *mmap_event = data;
+	struct vm_area_struct *vma = mmap_event->vma;
+	int executable = vma->vm_flags & VM_EXEC;
 
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_mmap_match(event, mmap_event, executable))
-			perf_event_mmap_output(event, mmap_event);
-	}
+	return (!executable && event->attr.mmap_data) ||
+	       (executable && event->attr.mmap);
 }
 
 static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
 	struct vm_area_struct *vma = mmap_event->vma;
 	struct file *file = vma->vm_file;
 	unsigned int size;
 	char tmp[16];
 	char *buf = NULL;
 	const char *name;
-	struct pmu *pmu;
-	int ctxn;
 
 	memset(tmp, 0, sizeof(tmp));
 
@@ -4831,27 +4784,10 @@ got_name:
 
 	mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_mmap_ctx(&cpuctx->ctx, mmap_event,
-					vma->vm_flags & VM_EXEC);
-
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx) {
-			perf_event_mmap_ctx(ctx, mmap_event,
-					vma->vm_flags & VM_EXEC);
-		}
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	rcu_read_unlock();
+	perf_event_aux(perf_event_mmap_match,
+		       perf_event_mmap_output,
+		       mmap_event,
+		       NULL);
 
 	kfree(buf);
 }
-- 
1.7.11.7

[tip:perf/urgent] perf: Factor out auxiliary events notification

[tip-bot for Jiri Olsa]

Commit-ID:  52d857a8784a09576215c71cebf368d61c12a754
Gitweb:     http://git.kernel.org/tip/52d857a8784a09576215c71cebf368d61c12a754
Author:     Jiri Olsa <jolsa@redhat.com>
AuthorDate: Mon, 6 May 2013 18:27:18 +0200
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 7 May 2013 13:17:29 +0200

perf: Factor out auxiliary events notification

Add perf_event_aux() function to send out all types of
auxiliary events - mmap, task, comm events. For each type
there's match and output functions defined and used as
callbacks during perf_event_aux processing.

This way we can centralize the pmu/context iterating and
event matching logic. Also since lot of the code was
duplicated, this patch reduces the .text size about 2kB
on my setup:

  snipped output from 'objdump -x kernel/events/core.o'

  before:
  Idx Name          Size
    0 .text         0000d313

  after:
  Idx Name          Size
    0 .text         0000cad3

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/1367857638-27631-3-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/events/core.c | 242 +++++++++++++++++++--------------------------------
 1 file changed, 89 insertions(+), 153 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 38b68a0..9dc297f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4394,6 +4394,64 @@ perf_event_read_event(struct perf_event *event,
 	perf_output_end(&handle);
 }
 
+typedef int  (perf_event_aux_match_cb)(struct perf_event *event, void *data);
+typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);
+
+static void
+perf_event_aux_ctx(struct perf_event_context *ctx,
+		   perf_event_aux_match_cb match,
+		   perf_event_aux_output_cb output,
+		   void *data)
+{
+	struct perf_event *event;
+
+	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+		if (event->state < PERF_EVENT_STATE_INACTIVE)
+			continue;
+		if (!event_filter_match(event))
+			continue;
+		if (match(event, data))
+			output(event, data);
+	}
+}
+
+static void
+perf_event_aux(perf_event_aux_match_cb match,
+	       perf_event_aux_output_cb output,
+	       void *data,
+	       struct perf_event_context *task_ctx)
+{
+	struct perf_cpu_context *cpuctx;
+	struct perf_event_context *ctx;
+	struct pmu *pmu;
+	int ctxn;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(pmu, &pmus, entry) {
+		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
+		if (cpuctx->unique_pmu != pmu)
+			goto next;
+		perf_event_aux_ctx(&cpuctx->ctx, match, output, data);
+		if (task_ctx)
+			goto next;
+		ctxn = pmu->task_ctx_nr;
+		if (ctxn < 0)
+			goto next;
+		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+		if (ctx)
+			perf_event_aux_ctx(ctx, match, output, data);
+next:
+		put_cpu_ptr(pmu->pmu_cpu_context);
+	}
+
+	if (task_ctx) {
+		preempt_disable();
+		perf_event_aux_ctx(task_ctx, match, output, data);
+		preempt_enable();
+	}
+	rcu_read_unlock();
+}
+
 /*
  * task tracking -- fork/exit
  *
@@ -4416,8 +4474,9 @@ struct perf_task_event {
 };
 
 static void perf_event_task_output(struct perf_event *event,
-				     struct perf_task_event *task_event)
+				   void *data)
 {
+	struct perf_task_event *task_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data	sample;
 	struct task_struct *task = task_event->task;
@@ -4445,64 +4504,11 @@ out:
 	task_event->event_id.header.size = size;
 }
 
-static int perf_event_task_match(struct perf_event *event)
-{
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if (event->attr.comm || event->attr.mmap ||
-	    event->attr.mmap_data || event->attr.task)
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_task_ctx(struct perf_event_context *ctx,
-				  struct perf_task_event *task_event)
-{
-	struct perf_event *event;
-
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_task_match(event))
-			perf_event_task_output(event, task_event);
-	}
-}
-
-static void perf_event_task_event(struct perf_task_event *task_event)
+static int perf_event_task_match(struct perf_event *event,
+				 void *data __maybe_unused)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx, *task_ctx = task_event->task_ctx;
-	struct pmu *pmu;
-	int ctxn;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_task_ctx(&cpuctx->ctx, task_event);
-
-		if (task_ctx)
-			goto next;
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx)
-			perf_event_task_ctx(ctx, task_event);
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	if (task_ctx) {
-		preempt_disable();
-		perf_event_task_ctx(task_ctx, task_event);
-		preempt_enable();
-	}
-
-	rcu_read_unlock();
+	return event->attr.comm || event->attr.mmap ||
+	       event->attr.mmap_data || event->attr.task;
 }
 
 static void perf_event_task(struct task_struct *task,
@@ -4533,7 +4539,10 @@ static void perf_event_task(struct task_struct *task,
 		},
 	};
 
-	perf_event_task_event(&task_event);
+	perf_event_aux(perf_event_task_match,
+		       perf_event_task_output,
+		       &task_event,
+		       task_ctx);
 }
 
 void perf_event_fork(struct task_struct *task)
@@ -4559,8 +4568,9 @@ struct perf_comm_event {
 };
 
 static void perf_event_comm_output(struct perf_event *event,
-				     struct perf_comm_event *comm_event)
+				   void *data)
 {
+	struct perf_comm_event *comm_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data sample;
 	int size = comm_event->event_id.header.size;
@@ -4587,39 +4597,16 @@ out:
 	comm_event->event_id.header.size = size;
 }
 
-static int perf_event_comm_match(struct perf_event *event)
-{
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if (event->attr.comm)
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_comm_ctx(struct perf_event_context *ctx,
-				  struct perf_comm_event *comm_event)
+static int perf_event_comm_match(struct perf_event *event,
+				 void *data __maybe_unused)
 {
-	struct perf_event *event;
-
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_comm_match(event))
-			perf_event_comm_output(event, comm_event);
-	}
+	return event->attr.comm;
 }
 
 static void perf_event_comm_event(struct perf_comm_event *comm_event)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
 	char comm[TASK_COMM_LEN];
 	unsigned int size;
-	struct pmu *pmu;
-	int ctxn;
 
 	memset(comm, 0, sizeof(comm));
 	strlcpy(comm, comm_event->task->comm, sizeof(comm));
@@ -4629,24 +4616,11 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	comm_event->comm_size = size;
 
 	comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_comm_ctx(&cpuctx->ctx, comm_event);
 
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx)
-			perf_event_comm_ctx(ctx, comm_event);
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	rcu_read_unlock();
+	perf_event_aux(perf_event_comm_match,
+		       perf_event_comm_output,
+		       comm_event,
+		       NULL);
 }
 
 void perf_event_comm(struct task_struct *task)
@@ -4708,8 +4682,9 @@ struct perf_mmap_event {
 };
 
 static void perf_event_mmap_output(struct perf_event *event,
-				     struct perf_mmap_event *mmap_event)
+				   void *data)
 {
+	struct perf_mmap_event *mmap_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data sample;
 	int size = mmap_event->event_id.header.size;
@@ -4736,46 +4711,24 @@ out:
 }
 
 static int perf_event_mmap_match(struct perf_event *event,
-				   struct perf_mmap_event *mmap_event,
-				   int executable)
+				 void *data)
 {
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if ((!executable && event->attr.mmap_data) ||
-	    (executable && event->attr.mmap))
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_mmap_ctx(struct perf_event_context *ctx,
-				  struct perf_mmap_event *mmap_event,
-				  int executable)
-{
-	struct perf_event *event;
+	struct perf_mmap_event *mmap_event = data;
+	struct vm_area_struct *vma = mmap_event->vma;
+	int executable = vma->vm_flags & VM_EXEC;
 
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_mmap_match(event, mmap_event, executable))
-			perf_event_mmap_output(event, mmap_event);
-	}
+	return (!executable && event->attr.mmap_data) ||
+	       (executable && event->attr.mmap);
 }
 
 static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
 	struct vm_area_struct *vma = mmap_event->vma;
 	struct file *file = vma->vm_file;
 	unsigned int size;
 	char tmp[16];
 	char *buf = NULL;
 	const char *name;
-	struct pmu *pmu;
-	int ctxn;
 
 	memset(tmp, 0, sizeof(tmp));
 
@@ -4831,27 +4784,10 @@ got_name:
 
 	mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_mmap_ctx(&cpuctx->ctx, mmap_event,
-					vma->vm_flags & VM_EXEC);
-
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx) {
-			perf_event_mmap_ctx(ctx, mmap_event,
-					vma->vm_flags & VM_EXEC);
-		}
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	rcu_read_unlock();
+	perf_event_aux(perf_event_mmap_match,
+		       perf_event_mmap_output,
+		       mmap_event,
+		       NULL);
 
 	kfree(buf);
 }

Re: [PATCH 0/2] perf: Fix/factor auxiliary events

[Peter Zijlstra]

On Mon, May 06, 2013 at 06:27:16PM +0200, Jiri Olsa wrote:
> hi,
> sending fix for issue caused by using smp_processor_id()
> in preemptible path discussed in here:
> http://marc.info/?l=linux-kernel&m=136733569907888&w=2
> 
> I also noticed there's a space for some code factoring
> saving some .text size and centralizing auxiliary
> events notification.

These look good, thanks!

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>