[V2,17/30] perf: changing pmu::setup_aux() parameter to include event

Message ID 1445192687-24112-18-git-send-email-mathieu.poirier@linaro.org
State New
Headers show

Commit Message

Mathieu Poirier Oct. 18, 2015, 6:24 p.m.
For some tracers the event carries information to be embedded
in the private structure returned by setup_aux().

As such changing the first parameter to be of type struct perf_event *
so that all the necessary information can be conveyed.  Also changing
current customer of the API to reflect the modification.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
 arch/x86/kernel/cpu/perf_event_intel_bts.c | 4 +++-
 arch/x86/kernel/cpu/perf_event_intel_pt.c  | 5 +++--
 include/linux/perf_event.h                 | 2 +-
 kernel/events/ring_buffer.c                | 2 +-
 4 files changed, 8 insertions(+), 5 deletions(-)


Alexander Shishkin Oct. 19, 2015, 1:34 p.m. | #1
Mathieu Poirier <mathieu.poirier@linaro.org> writes:

> For some tracers the event carries information to be embedded
> in the private structure returned by setup_aux().

You need to mention here what these tracers are and which bits of
event's information they need in their setup_aux(). Right now I can look
it up in this patchset, but when this code gets merged it will make it
easier to understand why this change was made.

Now, I understand that you're interested in event::attr in your
setup_aux(), I have more comments on that in that other patch. :)

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/


diff --git a/arch/x86/kernel/cpu/perf_event_intel_bts.c b/arch/x86/kernel/cpu/perf_event_intel_bts.c
index d1c0f254afbe..773600b2f313 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_bts.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_bts.c
@@ -68,10 +68,12 @@  static size_t buf_size(struct page *page)
 static void *
-bts_buffer_setup_aux(int cpu, void **pages, int nr_pages, bool overwrite)
+bts_buffer_setup_aux(struct perf_event *event, void **pages,
+		     int nr_pages, bool overwrite)
 	struct bts_buffer *buf;
 	struct page *page;
+	int cpu = event->cpu;
 	int node = (cpu == -1) ? cpu : cpu_to_node(cpu);
 	unsigned long offset;
 	size_t size = nr_pages << PAGE_SHIFT;
diff --git a/arch/x86/kernel/cpu/perf_event_intel_pt.c b/arch/x86/kernel/cpu/perf_event_intel_pt.c
index 42169283448b..f8b881210648 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_pt.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_pt.c
@@ -863,10 +863,11 @@  static int pt_buffer_init_topa(struct pt_buffer *buf, unsigned long nr_pages,
  * Return:	Our private PT buffer structure.
 static void *
-pt_buffer_setup_aux(int cpu, void **pages, int nr_pages, bool snapshot)
+pt_buffer_setup_aux(struct perf_event *event, void **pages,
+		    int nr_pages, bool snapshot)
 	struct pt_buffer *buf;
-	int node, ret;
+	int node, ret, cpu = event->cpu;
 	if (!nr_pages)
 		return NULL;
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 092a0e8a479a..0d9964b5ed4d 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -292,7 +292,7 @@  struct pmu {
 	 * Set up pmu-private data structures for an AUX area
-	void *(*setup_aux)		(int cpu, void **pages,
+	void *(*setup_aux)		(struct perf_event *event, void **pages,
 					 int nr_pages, bool overwrite);
 					/* optional */
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 182bc30899d5..87171b700c77 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -522,7 +522,7 @@  int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
 			goto out;
-	rb->aux_priv = event->pmu->setup_aux(event->cpu, rb->aux_pages, nr_pages,
+	rb->aux_priv = event->pmu->setup_aux(event, rb->aux_pages, nr_pages,
 	if (!rb->aux_priv)
 		goto out;