perf annotate: Add call target name if it is missing

The /proc/kcore file has no symbols, so the call target name does not
display.  Fix by looking up the symbol name if it is on the same map.
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
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: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-14-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/annotate.c

@@ -825,6 +825,22 @@ static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
 		dl->ops.target.offset = dl->ops.target.addr -
 					map__rip_2objdump(map, sym->start);
 
+	/*
+	 * kcore has no symbols, so add the call target name if it is on the
+	 * same map.
+	 */
+	if (dl->ins && ins__is_call(dl->ins) && !dl->ops.target.name) {
+		struct symbol *s;
+		u64 ip = dl->ops.target.addr;
+
+		if (ip >= map->start && ip <= map->end) {
+			ip = map->map_ip(map, ip);
+			s = map__find_symbol(map, ip, NULL);
+			if (s && s->start == ip)
+				dl->ops.target.name = strdup(s->name);
+		}
+	}
+
 	disasm__add(&notes->src->source, dl);
 
 	return 0;