libperf: Adopt perf_evsel__read() function from tools/perf

Move the perf_evsel__read() function to libperf as a public interface
together with struct perf_counts_values for returning counter values.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190721112506.12306-65-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/lib/evsel.c

@@ -12,6 +12,7 @@
 #include <internal/xyarray.h>
 #include <internal/cpumap.h>
 #include <internal/threadmap.h>
+#include <internal/lib.h>
 #include <linux/string.h>
 
 void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr)
@@ -137,3 +138,44 @@ void perf_evsel__close(struct perf_evsel *evsel)
 	perf_evsel__close_fd(evsel);
 	perf_evsel__free_fd(evsel);
 }
+
+int perf_evsel__read_size(struct perf_evsel *evsel)
+{
+	u64 read_format = evsel->attr.read_format;
+	int entry = sizeof(u64); /* value */
+	int size = 0;
+	int nr = 1;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+		size += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+		size += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_ID)
+		entry += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_GROUP) {
+		nr = evsel->nr_members;
+		size += sizeof(u64);
+	}
+
+	size += entry * nr;
+	return size;
+}
+
+int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
+		     struct perf_counts_values *count)
+{
+	size_t size = perf_evsel__read_size(evsel);
+
+	memset(count, 0, sizeof(*count));
+
+	if (FD(evsel, cpu, thread) < 0)
+		return -EINVAL;
+
+	if (readn(FD(evsel, cpu, thread), count->values, size) <= 0)
+		return -errno;
+
+	return 0;
+}

tools/perf/lib/include/internal/evsel.h

@@ -23,5 +23,6 @@ struct perf_evsel {
 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads);
 void perf_evsel__close_fd(struct perf_evsel *evsel);
 void perf_evsel__free_fd(struct perf_evsel *evsel);
+int perf_evsel__read_size(struct perf_evsel *evsel);
 
 #endif /* __LIBPERF_INTERNAL_EVSEL_H */

tools/perf/lib/include/perf/evsel.h

@@ -2,6 +2,7 @@
 #ifndef __LIBPERF_EVSEL_H
 #define __LIBPERF_EVSEL_H
 
+#include <stdint.h>
 #include <perf/core.h>
 
 struct perf_evsel;
@@ -9,6 +10,17 @@ struct perf_event_attr;
 struct perf_cpu_map;
 struct perf_thread_map;
 
+struct perf_counts_values {
+	union {
+		struct {
+			uint64_t val;
+			uint64_t ena;
+			uint64_t run;
+		};
+		uint64_t values[3];
+	};
+};
+
 LIBPERF_API void perf_evsel__init(struct perf_evsel *evsel,
 				  struct perf_event_attr *attr);
 LIBPERF_API struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr);
@@ -16,5 +28,7 @@ LIBPERF_API void perf_evsel__delete(struct perf_evsel *evsel);
 LIBPERF_API int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus,
 				 struct perf_thread_map *threads);
 LIBPERF_API void perf_evsel__close(struct perf_evsel *evsel);
+LIBPERF_API int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
+				 struct perf_counts_values *count);
 
 #endif /* __LIBPERF_EVSEL_H */

tools/perf/lib/libperf.map

@@ -16,6 +16,7 @@ LIBPERF_0.0.1 {
 		perf_evsel__init;
 		perf_evsel__open;
 		perf_evsel__close;
+		perf_evsel__read;
 		perf_evlist__new;
 		perf_evlist__delete;
 		perf_evlist__init;

tools/perf/tests/event-times.c

@@ -196,7 +196,7 @@ static int test_times(int (attach)(struct evlist *),
 
 	TEST_ASSERT_VAL("failed to detach", !detach(evlist));
 
-	perf_evsel__read(evsel, 0, 0, &count);
+	perf_evsel__read(&evsel->core, 0, 0, &count);
 
 	err = !(count.ena == count.run);
 

tools/perf/util/counts.h

@@ -3,17 +3,7 @@
 #define __PERF_COUNTS_H
 
 #include <internal/xyarray.h>
-
+#include <perf/evsel.h>
-struct perf_counts_values {
-	union {
-		struct {
-			u64 val;
-			u64 ena;
-			u64 run;
-		};
-		u64 values[3];
-	};
-};
 
 struct perf_counts {
 	s8			  scaled;

tools/perf/util/evsel.c

@@ -1346,53 +1346,12 @@ void perf_counts_values__scale(struct perf_counts_values *count,
 		*pscaled = scaled;
 }
 
-static int perf_evsel__read_size(struct evsel *evsel)
-{
-	u64 read_format = evsel->core.attr.read_format;
-	int entry = sizeof(u64); /* value */
-	int size = 0;
-	int nr = 1;
-
-	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
-		size += sizeof(u64);
-
-	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
-		size += sizeof(u64);
-
-	if (read_format & PERF_FORMAT_ID)
-		entry += sizeof(u64);
-
-	if (read_format & PERF_FORMAT_GROUP) {
-		nr = evsel->core.nr_members;
-		size += sizeof(u64);
-	}
-
-	size += entry * nr;
-	return size;
-}
-
-int perf_evsel__read(struct evsel *evsel, int cpu, int thread,
-		     struct perf_counts_values *count)
-{
-	size_t size = perf_evsel__read_size(evsel);
-
-	memset(count, 0, sizeof(*count));
-
-	if (FD(evsel, cpu, thread) < 0)
-		return -EINVAL;
-
-	if (readn(FD(evsel, cpu, thread), count->values, size) <= 0)
-		return -errno;
-
-	return 0;
-}
-
 static int
 perf_evsel__read_one(struct evsel *evsel, int cpu, int thread)
 {
 	struct perf_counts_values *count = perf_counts(evsel->counts, cpu, thread);
 
-	return perf_evsel__read(evsel, cpu, thread, count);
+	return perf_evsel__read(&evsel->core, cpu, thread, count);
 }
 
 static void
@@ -1453,7 +1412,7 @@ perf_evsel__read_group(struct evsel *leader, int cpu, int thread)
 {
 	struct perf_stat_evsel *ps = leader->stats;
 	u64 read_format = leader->core.attr.read_format;
-	int size = perf_evsel__read_size(leader);
+	int size = perf_evsel__read_size(&leader->core);
 	u64 *data = ps->group_data;
 
 	if (!(read_format & PERF_FORMAT_ID))

tools/perf/util/evsel.h

@@ -336,9 +336,6 @@ static inline bool perf_evsel__match2(struct evsel *e1,
 	 (a)->core.attr.type == (b)->core.attr.type &&	\
 	 (a)->core.attr.config == (b)->core.attr.config)
 
-int perf_evsel__read(struct evsel *evsel, int cpu, int thread,
-		     struct perf_counts_values *count);
-
 int perf_evsel__read_counter(struct evsel *evsel, int cpu, int thread);
 
 int __perf_evsel__read_on_cpu(struct evsel *evsel,