perf hists: Free unused mem info of a matched hist entry

The mem info is shared between matched entries so one should be freed.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@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>
Link: http://lkml.kernel.org/r/1364816125-12212-3-git-send-email-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/hist.c

@@ -374,6 +374,12 @@ static struct hist_entry *add_hist_entry(struct hists *hists,
 		if (!cmp) {
 			he_stat__add_period(&he->stat, period, weight);
 
+			/*
+			 * This mem info was allocated from machine__resolve_mem
+			 * and will not be used anymore.
+			 */
+			free(entry->mem_info);
+
 			/* If the map of an existing hist_entry has
 			 * become out-of-date due to an exec() or
 			 * similar, update it.  Otherwise we will