perf session: Allocate chunks of sample objects

The ordered sample code allocates singular reference objects struct
sample_queue which have 48byte size on 64bit and 20 bytes on 32bit. That's
silly. Allocate ~64k sized chunks and hand them out.

Performance gain: ~ 15%

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101130163820.398713983@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 19 insertions, 5 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 9fef587ff11f..52672dad1fe9 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -114,6 +114,7 @@ struct perf_session *perf_session__new(const char *filename, int mode, bool forc
         self->repipe = repipe;
         INIT_LIST_HEAD(&self->ordered_samples.samples);
         INIT_LIST_HEAD(&self->ordered_samples.sample_cache);
+        INIT_LIST_HEAD(&self->ordered_samples.to_free);
         machine__init(&self->host_machine, "", HOST_KERNEL_ID);
 
         if (mode == O_RDONLY) {
@@ -403,10 +404,10 @@ static void perf_session_free_sample_buffers(struct perf_session *session)
 {
         struct ordered_samples *os = &session->ordered_samples;
 
-        while (!list_empty(&os->sample_cache)) {
+        while (!list_empty(&os->to_free)) {
                 struct sample_queue *sq;
 
-                sq = list_entry(os->sample_cache.next, struct sample_queue, list);
+                sq = list_entry(os->to_free.next, struct sample_queue, list);
                 list_del(&sq->list);
                 free(sq);
         }
@@ -538,10 +539,13 @@ static void __queue_sample_event(struct sample_queue *new,
         }
 }
 
+#define MAX_SAMPLE_BUFFER       (64 * 1024 / sizeof(struct sample_queue))
+
 static int queue_sample_event(event_t *event, struct sample_data *data,
                               struct perf_session *s)
 {
-        struct list_head *sc = &s->ordered_samples.sample_cache;
+        struct ordered_samples *os = &s->ordered_samples;
+        struct list_head *sc = &os->sample_cache;
         u64 timestamp = data->time;
         struct sample_queue *new;
 
@@ -553,10 +557,17 @@ static int queue_sample_event(event_t *event, struct sample_data *data,
         if (!list_empty(sc)) {
                 new = list_entry(sc->next, struct sample_queue, list);
                 list_del(&new->list);
+        } else if (os->sample_buffer) {
+                new = os->sample_buffer + os->sample_buffer_idx;
+                if (++os->sample_buffer_idx == MAX_SAMPLE_BUFFER)
+                        os->sample_buffer = NULL;
         } else {
-                new = malloc(sizeof(*new));
-                if (!new)
+                os->sample_buffer = malloc(MAX_SAMPLE_BUFFER * sizeof(*new));
+                if (!os->sample_buffer)
                         return -ENOMEM;
+                list_add(&os->sample_buffer->list, &os->to_free);
+                os->sample_buffer_idx = 2;
+                new = os->sample_buffer + 1;
         }
 
         new->timestamp = timestamp;
diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index e4a7ff2ba8d5..5bf6efa3788a 100644
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -19,7 +19,10 @@ struct ordered_samples {
         u64                     max_timestamp;
         struct list_head        samples;
         struct list_head        sample_cache;
+        struct list_head        to_free;
+        struct sample_queue     *sample_buffer;
         struct sample_queue     *last_sample;
+        int                     sample_buffer_idx;
 };
 
 struct perf_session {