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authorLinus Torvalds <torvalds@linux-foundation.org>2008-10-20 16:35:07 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-20 16:35:07 -0400
commit92b29b86fe2e183d44eb467e5e74a5f718ef2e43 (patch)
tree1bac8a1aa11d47322b66d10ec3a370016d843d06 /include/linux/ring_buffer.h
parentb9d7ccf56be1ac77b71a284a1c0e6337f9a7aff0 (diff)
parent98d9c66ab07471006fd7910cb16453581c41a3e7 (diff)
Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (131 commits) tracing/fastboot: improve help text tracing/stacktrace: improve help text tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix bootgraph.pl initcall name regexp tracing/fastboot: fix issues and improve output of bootgraph.pl tracepoints: synchronize unregister static inline tracepoints: tracepoint_synchronize_unregister() ftrace: make ftrace_test_p6nop disassembler-friendly markers: fix synchronize marker unregister static inline tracing/fastboot: add better resolution to initcall debug/tracing trace: add build-time check to avoid overrunning hex buffer ftrace: fix hex output mode of ftrace tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix printk format typo in boot tracer ftrace: return an error when setting a nonexistent tracer ftrace: make some tracers reentrant ring-buffer: make reentrant ring-buffer: move page indexes into page headers tracing/fastboot: only trace non-module initcalls ftrace: move pc counter in irqtrace ... Manually fix conflicts: - init/main.c: initcall tracing - kernel/module.c: verbose level vs tracepoints - scripts/bootgraph.pl: fallout from cherry-picking commits.
Diffstat (limited to 'include/linux/ring_buffer.h')
-rw-r--r--include/linux/ring_buffer.h127
1 files changed, 127 insertions, 0 deletions
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
new file mode 100644
index 000000000000..536b0ca46a03
--- /dev/null
+++ b/include/linux/ring_buffer.h
@@ -0,0 +1,127 @@
1#ifndef _LINUX_RING_BUFFER_H
2#define _LINUX_RING_BUFFER_H
3
4#include <linux/mm.h>
5#include <linux/seq_file.h>
6
7struct ring_buffer;
8struct ring_buffer_iter;
9
10/*
11 * Don't reference this struct directly, use functions below.
12 */
13struct ring_buffer_event {
14 u32 type:2, len:3, time_delta:27;
15 u32 array[];
16};
17
18/**
19 * enum ring_buffer_type - internal ring buffer types
20 *
21 * @RINGBUF_TYPE_PADDING: Left over page padding
22 * array is ignored
23 * size is variable depending on how much
24 * padding is needed
25 *
26 * @RINGBUF_TYPE_TIME_EXTEND: Extend the time delta
27 * array[0] = time delta (28 .. 59)
28 * size = 8 bytes
29 *
30 * @RINGBUF_TYPE_TIME_STAMP: Sync time stamp with external clock
31 * array[0] = tv_nsec
32 * array[1] = tv_sec
33 * size = 16 bytes
34 *
35 * @RINGBUF_TYPE_DATA: Data record
36 * If len is zero:
37 * array[0] holds the actual length
38 * array[1..(length+3)/4-1] holds data
39 * else
40 * length = len << 2
41 * array[0..(length+3)/4] holds data
42 */
43enum ring_buffer_type {
44 RINGBUF_TYPE_PADDING,
45 RINGBUF_TYPE_TIME_EXTEND,
46 /* FIXME: RINGBUF_TYPE_TIME_STAMP not implemented */
47 RINGBUF_TYPE_TIME_STAMP,
48 RINGBUF_TYPE_DATA,
49};
50
51unsigned ring_buffer_event_length(struct ring_buffer_event *event);
52void *ring_buffer_event_data(struct ring_buffer_event *event);
53
54/**
55 * ring_buffer_event_time_delta - return the delta timestamp of the event
56 * @event: the event to get the delta timestamp of
57 *
58 * The delta timestamp is the 27 bit timestamp since the last event.
59 */
60static inline unsigned
61ring_buffer_event_time_delta(struct ring_buffer_event *event)
62{
63 return event->time_delta;
64}
65
66/*
67 * size is in bytes for each per CPU buffer.
68 */
69struct ring_buffer *
70ring_buffer_alloc(unsigned long size, unsigned flags);
71void ring_buffer_free(struct ring_buffer *buffer);
72
73int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size);
74
75struct ring_buffer_event *
76ring_buffer_lock_reserve(struct ring_buffer *buffer,
77 unsigned long length,
78 unsigned long *flags);
79int ring_buffer_unlock_commit(struct ring_buffer *buffer,
80 struct ring_buffer_event *event,
81 unsigned long flags);
82int ring_buffer_write(struct ring_buffer *buffer,
83 unsigned long length, void *data);
84
85struct ring_buffer_event *
86ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts);
87struct ring_buffer_event *
88ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts);
89
90struct ring_buffer_iter *
91ring_buffer_read_start(struct ring_buffer *buffer, int cpu);
92void ring_buffer_read_finish(struct ring_buffer_iter *iter);
93
94struct ring_buffer_event *
95ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts);
96struct ring_buffer_event *
97ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts);
98void ring_buffer_iter_reset(struct ring_buffer_iter *iter);
99int ring_buffer_iter_empty(struct ring_buffer_iter *iter);
100
101unsigned long ring_buffer_size(struct ring_buffer *buffer);
102
103void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu);
104void ring_buffer_reset(struct ring_buffer *buffer);
105
106int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
107 struct ring_buffer *buffer_b, int cpu);
108
109int ring_buffer_empty(struct ring_buffer *buffer);
110int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu);
111
112void ring_buffer_record_disable(struct ring_buffer *buffer);
113void ring_buffer_record_enable(struct ring_buffer *buffer);
114void ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu);
115void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu);
116
117unsigned long ring_buffer_entries(struct ring_buffer *buffer);
118unsigned long ring_buffer_overruns(struct ring_buffer *buffer);
119
120u64 ring_buffer_time_stamp(int cpu);
121void ring_buffer_normalize_time_stamp(int cpu, u64 *ts);
122
123enum ring_buffer_flags {
124 RB_FL_OVERWRITE = 1 << 0,
125};
126
127#endif /* _LINUX_RING_BUFFER_H */