perf tools: Annotate PMU related list_head members with type info

So that we can more readily understand in which list heads structs are
stored into.

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <michaele@au1.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1408087583-32239-6-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/pmu.c

@@ -14,8 +14,8 @@
 
 struct perf_pmu_alias {
 	char *name;
-	struct list_head terms;
-	struct list_head list;
+	struct list_head terms; /* HEAD struct parse_events_term -> list */
+	struct list_head list;  /* ELEM */
 	char unit[UNIT_MAX_LEN+1];
 	double scale;
 };

tools/perf/util/pmu.h

@@ -17,9 +17,9 @@ struct perf_pmu {
 	char *name;
 	__u32 type;
 	struct cpu_map *cpus;
-	struct list_head format;
-	struct list_head aliases;
-	struct list_head list;
+	struct list_head format;  /* HEAD struct perf_pmu_format -> list */
+	struct list_head aliases; /* HEAD struct perf_pmu_alias -> list */
+	struct list_head list;    /* ELEM */
 };
 
 struct perf_pmu *perf_pmu__find(const char *name);