[PATCH 10/49] perf tools: Add HEADER_DATA_INDEX feature

[Jiri Olsa]

From: Namhyung Kim <namhyung@xxxxxxxxxx>

The HEADER_DATA_INDEX feature is to record index table for sample data
so that they can be processed by multiple thread concurrently.  Each
item is a struct perf_file_section which consists of an offset and size.

Link: http://lkml.kernel.org/n/tip-q5rh23fs1qlenc2s9fj0ug7u@xxxxxxxxxxxxxx
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
 tools/perf/builtin-record.c |  1 +
 tools/perf/util/header.c    | 76 +++++++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/header.h    |  3 ++
 3 files changed, 80 insertions(+)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 385aa9fba282..e52be5593b2f 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -579,6 +579,7 @@ static void record__init_features(struct record *rec)
 		perf_header__clear_feat(&session->header, HEADER_AUXTRACE);
 
 	perf_header__clear_feat(&session->header, HEADER_STAT);
+	perf_header__clear_feat(&session->header, HEADER_DATA_INDEX);
 }
 
 static void
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 418608a7c91a..e947a380eddb 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -33,6 +33,7 @@
 #include "strbuf.h"
 #include "build-id.h"
 #include "data.h"
+#include "units.h"
 #include <api/fs/fs.h>
 #include "asm/bug.h"
 #include "tool.h"
@@ -1196,6 +1197,25 @@ static int write_sample_time(struct feat_fd *ff,
 			sizeof(evlist->last_sample_time));
 }
 
+static int write_data_index(struct feat_fd *ff,
+			    struct perf_evlist *evlist __maybe_unused)
+{
+	struct perf_header *ph = ff->ph;
+	int ret;
+	unsigned int i;
+
+	ret = do_write(ff, &ph->nr_index, sizeof(ph->nr_index));
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < ph->nr_index; i++) {
+		ret = do_write(ff, &ph->index[i], sizeof(*ph->index));
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
 static void print_hostname(struct feat_fd *ff, FILE *fp)
 {
 	fprintf(fp, "# hostname : %s\n", ff->ph->env.hostname);
@@ -1543,6 +1563,23 @@ static void print_sample_time(struct feat_fd *ff, FILE *fp)
 	fprintf(fp, "# sample duration : %10.3f ms\n", d);
 }
 
+static void print_data_index(struct feat_fd *ff, FILE *fp)
+{
+	struct perf_header *ph = ff->ph;
+	unsigned int i;
+
+	fprintf(fp, "# contains data index (%lu) for parallel processing\n",
+		ph->nr_index);
+
+	for (i = 0; i < ph->nr_index; i++) {
+		struct perf_file_section *s = &ph->index[i];
+		char buf[20];
+
+		unit_number__scnprintf(buf, sizeof(buf), s->size);
+		fprintf(fp, "#   %u: %s @ %lu\n", i, buf, s->offset);
+	}
+}
+
 static int __event_process_build_id(struct build_id_event *bev,
 				    char *filename,
 				    struct perf_session *session)
@@ -2205,6 +2242,44 @@ static int process_sample_time(struct feat_fd *ff, void *data __maybe_unused)
 	return 0;
 }
 
+static int process_data_index(struct feat_fd *ff, void *data __maybe_unused)
+{
+	struct perf_header *ph = ff->ph;
+	int fd = ff->fd;
+	ssize_t ret;
+	u64 nr_idx;
+	unsigned int i;
+	struct perf_file_section *idx;
+
+	ret = readn(fd, &nr_idx, sizeof(nr_idx));
+	if (ret != sizeof(nr_idx))
+		return -1;
+
+	if (ph->needs_swap)
+		nr_idx = bswap_64(nr_idx);
+
+	idx = calloc(nr_idx, sizeof(*idx));
+	if (idx == NULL)
+		return -1;
+
+	for (i = 0; i < nr_idx; i++) {
+		ret = readn(fd, &idx[i], sizeof(*idx));
+		if (ret != sizeof(*idx)) {
+			free(idx);
+			return -1;
+		}
+
+		if (ph->needs_swap) {
+			idx[i].offset = bswap_64(idx[i].offset);
+			idx[i].size   = bswap_64(idx[i].size);
+		}
+	}
+
+	ph->index = idx;
+	ph->nr_index = nr_idx;
+	return 0;
+}
+
 struct feature_ops {
 	int (*write)(struct feat_fd *ff, struct perf_evlist *evlist);
 	void (*print)(struct feat_fd *ff, FILE *fp);
@@ -2263,6 +2338,7 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
 	FEAT_OPN(STAT,		stat,		false),
 	FEAT_OPN(CACHE,		cache,		true),
 	FEAT_OPR(SAMPLE_TIME,	sample_time,	false),
+	FEAT_OPN(DATA_INDEX,	data_index,	true),
 };
 
 struct header_print_data {
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index fa8025fbe90d..cc8b651e779a 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -36,6 +36,7 @@ enum {
 	HEADER_STAT,
 	HEADER_CACHE,
 	HEADER_SAMPLE_TIME,
+	HEADER_DATA_INDEX,
 	HEADER_LAST_FEATURE,
 	HEADER_FEAT_BITS	= 256,
 };
@@ -76,6 +77,8 @@ struct perf_header {
 	bool				needs_swap;
 	u64				data_offset;
 	u64				data_size;
+	struct perf_file_section	*index;
+	u64				nr_index;
 	u64				feat_offset;
 	DECLARE_BITMAP(adds_features, HEADER_FEAT_BITS);
 	struct perf_env 	env;
-- 
2.13.6