Merge branch 'master' into next

1 files changed, 31 insertions, 0 deletions

diff --git a/kernel/trace/trace_stat.h b/kernel/trace/trace_stat.h
new file mode 100644
index 000000000000..202274cf7f3d
--- /dev/null
+++ b/kernel/trace/trace_stat.h
@@ -0,0 +1,31 @@
+#ifndef __TRACE_STAT_H
+#define __TRACE_STAT_H
+
+#include <linux/seq_file.h>
+
+/*
+ * 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 stats sorting */
+	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);
+};
+
+/*
+ * Destroy or create a stat file
+ */
+extern int register_stat_tracer(struct tracer_stat *trace);
+extern void unregister_stat_tracer(struct tracer_stat *trace);
+
+#endif /* __TRACE_STAT_H */