perf util: Use evsel->name to get tracepoint_paths

Most tracepoint events already have their system and event name in
->name field so that searching whole event tracing directory for each
evsel to match given id is suboptimal.

Factor out this routine into tracepoint_name_to_path().  In case of en
invalid name, it'll try to find path using id again.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1372230862-15861-3-git-send-email-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/parse-events.c

@@ -217,6 +217,29 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config)
 	return NULL;
 }
 
+struct tracepoint_path *tracepoint_name_to_path(const char *name)
+{
+	struct tracepoint_path *path = zalloc(sizeof(*path));
+	char *str = strchr(name, ':');
+
+	if (path == NULL || str == NULL) {
+		free(path);
+		return NULL;
+	}
+
+	path->system = strndup(name, str - name);
+	path->name = strdup(str+1);
+
+	if (path->system == NULL || path->name == NULL) {
+		free(path->system);
+		free(path->name);
+		free(path);
+		path = NULL;
+	}
+
+	return path;
+}
+
 const char *event_type(int type)
 {
 	switch (type) {

tools/perf/util/parse-events.h

@@ -23,6 +23,7 @@ struct tracepoint_path {
 };
 
 extern struct tracepoint_path *tracepoint_id_to_path(u64 config);
+extern struct tracepoint_path *tracepoint_name_to_path(const char *name);
 extern bool have_tracepoints(struct list_head *evlist);
 
 const char *event_type(int type);

tools/perf/util/trace-event-info.c

@@ -414,12 +414,27 @@ get_tracepoints_path(struct list_head *pattrs)
 		if (pos->attr.type != PERF_TYPE_TRACEPOINT)
 			continue;
 		++nr_tracepoints;
+
+		if (pos->name) {
+			ppath->next = tracepoint_name_to_path(pos->name);
+			if (ppath->next)
+				goto next;
+
+			if (strchr(pos->name, ':') == NULL)
+				goto try_id;
+
+			goto error;
+		}
+
+try_id:
 		ppath->next = tracepoint_id_to_path(pos->attr.config);
 		if (!ppath->next) {
+error:
 			pr_debug("No memory to alloc tracepoints list\n");
 			put_tracepoints_path(&path);
 			return NULL;
 		}
+next:
 		ppath = ppath->next;
 	}