[PATCH 33/59] perf evlist: Introduce perf_evlist__new_dummy constructor

From: Arnaldo Carvalho de Melo
Date: Fri Jan 08 2016 - 13:19:47 EST


From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

For case where all we need is an evlist with just an "dummy" evsel,
like in some 'perf test' entries.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-q52le0pblm2k3ncvyilelr9z@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/evlist.c | 28 ++++++++++++++++++++++++++++
tools/perf/util/evlist.h | 3 +++
2 files changed, 31 insertions(+)

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index b9eac0daa0b9..fa6dbf0ea0d6 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -68,6 +68,18 @@ struct perf_evlist *perf_evlist__new_default(void)
return evlist;
}

+struct perf_evlist *perf_evlist__new_dummy(void)
+{
+ struct perf_evlist *evlist = perf_evlist__new();
+
+ if (evlist && perf_evlist__add_dummy(evlist)) {
+ perf_evlist__delete(evlist);
+ evlist = NULL;
+ }
+
+ return evlist;
+}
+
/**
* perf_evlist__set_id_pos - set the positions of event ids.
* @evlist: selected event list
@@ -248,6 +260,22 @@ error:
return -ENOMEM;
}

+int perf_evlist__add_dummy(struct perf_evlist *evlist)
+{
+ struct perf_event_attr attr = {
+ .type = PERF_TYPE_SOFTWARE,
+ .config = PERF_COUNT_SW_DUMMY,
+ .size = sizeof(attr), /* to capture ABI version */
+ };
+ struct perf_evsel *evsel = perf_evsel__new(&attr);
+
+ if (evsel == NULL)
+ return -ENOMEM;
+
+ perf_evlist__add(evlist, evsel);
+ return 0;
+}
+
static int perf_evlist__add_attrs(struct perf_evlist *evlist,
struct perf_event_attr *attrs, size_t nr_attrs)
{
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 139a50038097..3b7e1e2f1a86 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -67,6 +67,7 @@ struct perf_evsel_str_handler {

struct perf_evlist *perf_evlist__new(void);
struct perf_evlist *perf_evlist__new_default(void);
+struct perf_evlist *perf_evlist__new_dummy(void);
void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
struct thread_map *threads);
void perf_evlist__exit(struct perf_evlist *evlist);
@@ -81,6 +82,8 @@ int __perf_evlist__add_default_attrs(struct perf_evlist *evlist,
#define perf_evlist__add_default_attrs(evlist, array) \
__perf_evlist__add_default_attrs(evlist, array, ARRAY_SIZE(array))

+int perf_evlist__add_dummy(struct perf_evlist *evlist);
+
int perf_evlist__add_newtp(struct perf_evlist *evlist,
const char *sys, const char *name, void *handler);

--
2.1.0