1 files changed, 12 insertions, 4 deletions

diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index e097c2e6b6dc..d363467c8f13 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -28,17 +28,19 @@ struct ring_buffer_event {
  *                               size = 8 bytes
  *
  * @RINGBUF_TYPE_TIME_STAMP:    Sync time stamp with external clock
- *                               array[0] = tv_nsec
- *                               array[1] = tv_sec
+ *                               array[0]    = tv_nsec
+ *                               array[1..2] = tv_sec
  *                               size = 16 bytes
  *
  * @RINGBUF_TYPE_DATA:          Data record
  *                               If len is zero:
  *                                array[0] holds the actual length
- *                                array[1..(length+3)/4-1] holds data
+ *                                array[1..(length+3)/4] holds data
+ *                                size = 4 + 4 + length (bytes)
  *                               else
  *                                length = len << 2
- *                                array[0..(length+3)/4] holds data
+ *                                array[0..(length+3)/4-1] holds data
+ *                                size = 4 + length (bytes)
  */
 enum ring_buffer_type {
         RINGBUF_TYPE_PADDING,
@@ -122,6 +124,12 @@ void ring_buffer_normalize_time_stamp(int cpu, u64 *ts);
 
 void tracing_on(void);
 void tracing_off(void);
+void tracing_off_permanent(void);
+
+void *ring_buffer_alloc_read_page(struct ring_buffer *buffer);
+void ring_buffer_free_read_page(struct ring_buffer *buffer, void *data);
+int ring_buffer_read_page(struct ring_buffer *buffer,
+                          void **data_page, int cpu, int full);
 
 enum ring_buffer_flags {
         RB_FL_OVERWRITE         = 1 << 0,