perf/tool: Add PMU event alias support

Add support to specify alias term within the event description.

The definition of pmu event alias is located at:

  ${sysfs_mount}/bus/event_source/devices/${pmu}/events/

Each file in the 'events' directory defines a event alias. Its contents
are like:

  config=1,config1=2

Using pmu event alias, an event can be now specified like:

  uncore/CLOCKTICKS/ or uncore/event=CLOCKTICKS/

Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
[ Cleaned it up. ]
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1339741902-8449-13-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 9896eda..a2c7168 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -78,6 +78,8 @@
 			   int type_term, char *config, long num);
 int parse_events__term_str(struct parse_events__term **_term,
 			   int type_term, char *config, char *str);
+int parse_events__term_clone(struct parse_events__term **new,
+			     struct parse_events__term *term);
 void parse_events__free_terms(struct list_head *terms);
 int parse_events_modifier(struct list_head *list, char *str);
 int parse_events_add_tracepoint(struct list_head **list, int *idx,