perf mmap: Use the stored scope data in perf_mmap__push()

Using the 'start' and 'end' which are stored in struct perf_mmap to
replace the temporary 'start' and 'end'.
The temporary variables will be discarded later.

It doesn't need to pass 'overwrite' to perf_mmap__push(). It's stored in
struct perf_mmap.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1520350567-80082-3-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.h b/tools/perf/util/mmap.h
index 9359e93..65f5b26 100644
--- a/tools/perf/util/mmap.h
+++ b/tools/perf/util/mmap.h
@@ -93,8 +93,8 @@ union perf_event *perf_mmap__read_event(struct perf_mmap *map,
 					bool overwrite,
 					u64 *startp, u64 end);
 
-int perf_mmap__push(struct perf_mmap *md, bool backward,
-		    void *to, int push(void *to, void *buf, size_t size));
+int perf_mmap__push(struct perf_mmap *md, void *to,
+		    int push(void *to, void *buf, size_t size));
 
 size_t perf_mmap__mmap_len(struct perf_mmap *map);