perf hist: Introduce hists class and move lots of methods to it

In cbbc79a we introduced support for multiple events by introducing a
new "event_stat_id" struct and then made several perf_session methods
receive a point to it instead of a pointer to perf_session, and kept the
event_stats and hists rb_tree in perf_session.

While working on the new newt based browser, I realised that it would be
better to introduce a new class, "hists" (short for "histograms"),
renaming the "event_stat_id" struct and the perf_session methods that
were really "hists" methods, as they manipulate only struct hists
members, not touching anything in the other perf_session members.

Other optimizations, such as calculating the maximum lenght of a symbol
name present in an hists instance will be possible as we add them,
avoiding a re-traversal just for finding that information.

The rationale for the name "hists" to replace "event_stat_id" is that we
may have multiple sets of hists for the same event_stat id, as, for
instance, the 'perf diff' tool has, so event stat id is not what
characterizes what this struct and the functions that manipulate it do.

Cc: Eric B Munson <ebmunson@us.ibm.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 27 insertions, 21 deletions

diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index b49013adb34b..bdde81eca69f 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -6,34 +6,40 @@
 
 extern struct callchain_param callchain_param;
 
-struct perf_session;
 struct hist_entry;
 struct addr_location;
 struct symbol;
 struct rb_root;
 
-struct hist_entry *__perf_session__add_hist_entry(struct rb_root *hists,
-						  struct addr_location *al,
-						  struct symbol *parent,
-						  u64 count);
+struct events_stats {
+	u64 total;
+	u64 lost;
+};
+
+struct hists {
+	struct rb_node		rb_node;
+	struct rb_root		entries;
+	struct events_stats	stats;
+	u64			config;
+	u64			event_stream;
+	u32			type;
+};
+
+struct hist_entry *__hists__add_entry(struct hists *self,
+				      struct addr_location *al,
+				      struct symbol *parent, u64 count);
 extern int64_t hist_entry__cmp(struct hist_entry *, struct hist_entry *);
 extern int64_t hist_entry__collapse(struct hist_entry *, struct hist_entry *);
-int hist_entry__fprintf(struct hist_entry *self,
-			   struct perf_session *pair_session,
-			   bool show_displacement,
-			   long displacement, FILE *fp,
-			   u64 session_total);
-int hist_entry__snprintf(struct hist_entry *self,
-			 char *bf, size_t size,
-			 struct perf_session *pair_session,
-			 bool show_displacement, long displacement,
-			 bool color, u64 session_total);
+int hist_entry__fprintf(struct hist_entry *self, struct hists *pair_hists,
+			bool show_displacement, long displacement, FILE *fp,
+			u64 total);
+int hist_entry__snprintf(struct hist_entry *self, char *bf, size_t size,
+			 struct hists *pair_hists, bool show_displacement,
+			 long displacement, bool color, u64 total);
 void hist_entry__free(struct hist_entry *);
 
-u64 perf_session__output_resort(struct rb_root *hists, u64 total_samples);
-void perf_session__collapse_resort(struct rb_root *hists);
-size_t perf_session__fprintf_hists(struct rb_root *hists,
-				   struct perf_session *pair,
-				   bool show_displacement, FILE *fp,
-				   u64 session_total);
+u64 hists__output_resort(struct hists *self);
+void hists__collapse_resort(struct hists *self);
+size_t hists__fprintf(struct hists *self, struct hists *pair,
+		      bool show_displacement, FILE *fp);
 #endif	/* __PERF_HIST_H */