libperf: Add perf_evsel__new() function

Add a perf_evsel__new() function to create and init a perf_evsel struct
dynamicaly.
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/20190721112506.12306-47-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/lib/evsel.c

@@ -2,9 +2,20 @@
 #include <perf/evsel.h>
 #include <linux/list.h>
 #include <internal/evsel.h>
+#include <linux/zalloc.h>
 
 void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr)
 {
 	INIT_LIST_HEAD(&evsel->node);
 	evsel->attr = *attr;
 }
+
+struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr)
+{
+	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
+
+	if (evsel != NULL)
+		perf_evsel__init(evsel, attr);
+
+	return evsel;
+}

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

@@ -9,5 +9,6 @@ struct perf_event_attr;
 
 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);
 
 #endif /* __LIBPERF_EVSEL_H */

tools/perf/lib/libperf.map

@@ -11,6 +11,7 @@ LIBPERF_0.0.1 {
 		perf_thread_map__comm;
 		perf_thread_map__get;
 		perf_thread_map__put;
+		perf_evsel__new;
 		perf_evsel__init;
 		perf_evlist__new;
 		perf_evlist__init;