tracing/ftrace: separate events tracing and stats tracing engine

Impact: tracing's Api change

Currently, the stat tracing depends on the events tracing.
When you switch to a new tracer, the stats files of the previous tracer
will disappear. But it's more scalable to separate those two engines.
This way, we can keep the stat files of one or several tracers when we
want, without bothering of multiple tracer stat files or tracer switching.

To build/destroys its stats files, a tracer just have to call
register_stat_tracer/unregister_stat_tracer everytimes it wants to.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 0 insertions, 20 deletions

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b3f9ad1b4d84..79c872100dd5 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -334,24 +334,6 @@ struct tracer_flags {
 /* Makes more easy to define a tracer opt */
 #define TRACER_OPT(s, b)        .name = #s, .bit = b
 
-/*
- * If you want to provide a stat file (one-shot statistics), fill
- * an iterator with stat_start/stat_next and a stat_show callbacks.
- * The others callbacks are optional.
- */
-struct tracer_stat {
-        /* The name of your stat file */
-        const char              *name;
-        /* Iteration over statistic entries */
-        void                    *(*stat_start)(void);
-        void                    *(*stat_next)(void *prev, int idx);
-        /* Compare two entries for sorting (optional) for stats */
-        int                     (*stat_cmp)(void *p1, void *p2);
-        /* Print a stat entry */
-        int                     (*stat_show)(struct seq_file *s, void *p);
-        /* Print the headers of your stat entries */
-        int                     (*stat_headers)(struct seq_file *s);
-};
 
 /*
  * A specific tracer, represented by methods that operate on a trace array:
@@ -466,8 +448,6 @@ void tracing_start_sched_switch_record(void);
 int register_tracer(struct tracer *type);
 void unregister_tracer(struct tracer *type);
 
-void init_tracer_stat(struct tracer *trace);
-
 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 
 extern unsigned long tracing_max_latency;