perf tools: Add ->cmp(), ->collapse() and ->sort() to perf_hpp_fmt

Those function pointers will be used to sort report output based on
the selected fields.  This is a preparation of later change.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/1400480762-22852-2-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 38c3e874c164..36dbe00e3cc8 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -160,6 +160,9 @@ struct perf_hpp_fmt {
                      struct hist_entry *he);
         int (*entry)(struct perf_hpp_fmt *fmt, struct perf_hpp *hpp,
                      struct hist_entry *he);
+        int64_t (*cmp)(struct hist_entry *a, struct hist_entry *b);
+        int64_t (*collapse)(struct hist_entry *a, struct hist_entry *b);
+        int64_t (*sort)(struct hist_entry *a, struct hist_entry *b);
 
         struct list_head list;
 };