perf mmap: Use stored 'overwrite' in perf_mmap__consume()

The 'overwrite' is set at allocation. It will not be changed.  Using it
to replace the parameter of perf_mmap__consume().  The parameters will
be discarded later.

No functional change.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1520350567-80082-5-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c
index 2933942..8a2dac9 100644
--- a/tools/perf/util/mmap.c
+++ b/tools/perf/util/mmap.c
@@ -118,9 +118,9 @@ void perf_mmap__put(struct perf_mmap *map)
 		perf_mmap__munmap(map);
 }
 
-void perf_mmap__consume(struct perf_mmap *map, bool overwrite)
+void perf_mmap__consume(struct perf_mmap *map, bool overwrite __maybe_unused)
 {
-	if (!overwrite) {
+	if (!map->overwrite) {
 		u64 old = map->prev;
 
 		perf_mmap__write_tail(map, old);