perf tools: Add struct perf_data_file

Add struct perf_data_file to represent a single file within a perf_data
struct.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Changbin Du <changbin.du@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-c3f9p4xzykr845ktqcek6p4t@git.kernel.org
[ Fixup recent changes in 'perf script --per-event-dump' ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index d45740a..abcab75 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -1949,7 +1949,7 @@ int cmd_kmem(int argc, const char **argv)
 		return __cmd_record(argc, argv);
 	}
 
-	data.path = input_name;
+	data.file.path = input_name;
 
 	kmem_session = session = perf_session__new(&data, false, &perf_kmem);
 	if (session == NULL)