#ifndef _LINUX_RING_BUFFER_H
#define _LINUX_RING_BUFFER_H
+#include <linux/kmemcheck.h>
#include <linux/mm.h>
#include <linux/seq_file.h>
* Don't refer to this struct directly, use functions below.
*/
struct ring_buffer_event {
- u32 type:2, len:3, time_delta:27;
+ kmemcheck_bitfield_begin(bitfield);
+ u32 type_len:5, time_delta:27;
+ kmemcheck_bitfield_end(bitfield);
+
u32 array[];
};
/**
* 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:
+ * array[0] holds the actual length
+ * size = 4 + length (bytes)
*
* @RINGBUF_TYPE_TIME_EXTEND: Extend the time delta
* array[0] = time delta (28 .. 59)
* array[1..2] = tv_sec
* size = 16 bytes
*
- * @RINGBUF_TYPE_DATA: Data record
- * If len is zero:
+ * <= @RINGBUF_TYPE_DATA_TYPE_LEN_MAX:
+ * Data record
+ * If type_len is zero:
* array[0] holds the actual length
* array[1..(length+3)/4] holds data
- * size = 4 + 4 + length (bytes)
+ * size = 4 + length (bytes)
* else
- * length = len << 2
+ * length = type_len << 2
* array[0..(length+3)/4-1] holds data
* size = 4 + length (bytes)
*/
enum ring_buffer_type {
+ RINGBUF_TYPE_DATA_TYPE_LEN_MAX = 28,
RINGBUF_TYPE_PADDING,
RINGBUF_TYPE_TIME_EXTEND,
/* FIXME: RINGBUF_TYPE_TIME_STAMP not implemented */
RINGBUF_TYPE_TIME_STAMP,
- RINGBUF_TYPE_DATA,
};
unsigned ring_buffer_event_length(struct ring_buffer_event *event);
}
/*
+ * ring_buffer_discard_commit will remove an event that has not
+ * ben committed yet. If this is used, then ring_buffer_unlock_commit
+ * must not be called on the discarded event. This function
+ * will try to remove the event from the ring buffer completely
+ * if another event has not been written after it.
+ *
+ * Example use:
+ *
+ * if (some_condition)
+ * ring_buffer_discard_commit(buffer, event);
+ * else
+ * ring_buffer_unlock_commit(buffer, event);
+ */
+void ring_buffer_discard_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event);
+
+/*
* size is in bytes for each per CPU buffer.
*/
struct ring_buffer *
-ring_buffer_alloc(unsigned long size, unsigned flags);
+__ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *key);
+
+/*
+ * Because the ring buffer is generic, if other users of the ring buffer get
+ * traced by ftrace, it can produce lockdep warnings. We need to keep each
+ * ring buffer's lock class separate.
+ */
+#define ring_buffer_alloc(size, flags) \
+({ \
+ static struct lock_class_key __key; \
+ __ring_buffer_alloc((size), (flags), &__key); \
+})
+
void ring_buffer_free(struct ring_buffer *buffer);
int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size);
void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu);
void ring_buffer_reset(struct ring_buffer *buffer);
+#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
struct ring_buffer *buffer_b, int cpu);
+#else
+static inline int
+ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
+ struct ring_buffer *buffer_b, int cpu)
+{
+ return -ENODEV;
+}
+#endif
int ring_buffer_empty(struct ring_buffer *buffer);
int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu);
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);
+unsigned long ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu);
-u64 ring_buffer_time_stamp(int cpu);
-void ring_buffer_normalize_time_stamp(int cpu, u64 *ts);
+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));
size_t ring_buffer_page_len(void *page);
int ring_buffer_read_page(struct ring_buffer *buffer, void **data_page,
size_t len, int cpu, int full);
+struct trace_seq;
+
+int ring_buffer_print_entry_header(struct trace_seq *s);
+int ring_buffer_print_page_header(struct trace_seq *s);
+
enum ring_buffer_flags {
RB_FL_OVERWRITE = 1 << 0,
};