clocksource: add enable() and disable() callbacks

[safe/jmp/linux-2.6] / include / linux / ring_buffer.h

diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index 1a350a8..e1b7b21 100644 (file)
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -8,7 +8,7 @@ struct ring_buffer;
 struct ring_buffer_iter;
 
 /*
- * Don't reference this struct directly, use functions below.
+ * Don't refer to this struct directly, use functions below.
  */
 struct ring_buffer_event {
        u32             type:2, len:3, time_delta:27;
@@ -18,27 +18,32 @@ struct ring_buffer_event {
 /**
  * enum ring_buffer_type - internal ring buffer types
  *
- * @RINGBUF_TYPE_PADDING:      Left over page padding
- *                              array is ignored
- *                              size is variable depending on how much
+ * @RINGBUF_TYPE_PADDING:      Left over page padding or discarded event
+ *                              If time_delta is 0:
+ *                               array is ignored
+ *                               size is variable depending on how much
  *                               padding is needed
+ *                              If time_delta is non zero:
+ *                               everything else same as RINGBUF_TYPE_DATA
  *
  * @RINGBUF_TYPE_TIME_EXTEND:  Extend the time delta
  *                              array[0] = time delta (28 .. 59)
  *                              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,
@@ -63,6 +68,8 @@ ring_buffer_event_time_delta(struct ring_buffer_event *event)
        return event->time_delta;
 }
 
+void ring_buffer_event_discard(struct ring_buffer_event *event);
+
 /*
  * size is in bytes for each per CPU buffer.
  */
@@ -72,13 +79,10 @@ void ring_buffer_free(struct ring_buffer *buffer);
 
 int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size);
 
-struct ring_buffer_event *
-ring_buffer_lock_reserve(struct ring_buffer *buffer,
-                        unsigned long length,
-                        unsigned long *flags);
+struct ring_buffer_event *ring_buffer_lock_reserve(struct ring_buffer *buffer,
+                                                  unsigned long length);
 int ring_buffer_unlock_commit(struct ring_buffer *buffer,
-                             struct ring_buffer_event *event,
-                             unsigned long flags);
+                             struct ring_buffer_event *event);
 int ring_buffer_write(struct ring_buffer *buffer,
                      unsigned long length, void *data);
 
@@ -116,18 +120,22 @@ void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu);
 
 unsigned long ring_buffer_entries(struct ring_buffer *buffer);
 unsigned long ring_buffer_overruns(struct ring_buffer *buffer);
+unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu);
+unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu);
+
+u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu);
+void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer,
+                                     int cpu, u64 *ts);
+void ring_buffer_set_clock(struct ring_buffer *buffer,
+                          u64 (*clock)(void));
 
-u64 ring_buffer_time_stamp(int cpu);
-void ring_buffer_normalize_time_stamp(int cpu, u64 *ts);
+size_t ring_buffer_page_len(void *page);
 
-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);
+int ring_buffer_read_page(struct ring_buffer *buffer, void **data_page,
+                         size_t len, int cpu, int full);
 
 enum ring_buffer_flags {
        RB_FL_OVERWRITE         = 1 << 0,