1#ifndef _LINUX_RING_BUFFER_H
2#define _LINUX_RING_BUFFER_H
3
4#include <linux/kmemcheck.h>
5#include <linux/mm.h>
6#include <linux/seq_file.h>
7#include <linux/poll.h>
8
9struct ring_buffer;
10struct ring_buffer_iter;
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15struct ring_buffer_event {
16 kmemcheck_bitfield_begin(bitfield);
17 u32 type_len:5, time_delta:27;
18 kmemcheck_bitfield_end(bitfield);
19
20 u32 array[];
21};
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54
55enum ring_buffer_type {
56 RINGBUF_TYPE_DATA_TYPE_LEN_MAX = 28,
57 RINGBUF_TYPE_PADDING,
58 RINGBUF_TYPE_TIME_EXTEND,
59
60 RINGBUF_TYPE_TIME_STAMP,
61};
62
63unsigned ring_buffer_event_length(struct ring_buffer_event *event);
64void *ring_buffer_event_data(struct ring_buffer_event *event);
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80void ring_buffer_discard_commit(struct ring_buffer *buffer,
81 struct ring_buffer_event *event);
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85
86struct ring_buffer *
87__ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *key);
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93
94#define ring_buffer_alloc(size, flags) \
95({ \
96 static struct lock_class_key __key; \
97 __ring_buffer_alloc((size), (flags), &__key); \
98})
99
100void ring_buffer_wait(struct ring_buffer *buffer, int cpu);
101int ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu,
102 struct file *filp, poll_table *poll_table);
103
104
105#define RING_BUFFER_ALL_CPUS -1
106
107void ring_buffer_free(struct ring_buffer *buffer);
108
109int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size, int cpu);
110
111void ring_buffer_change_overwrite(struct ring_buffer *buffer, int val);
112
113struct ring_buffer_event *ring_buffer_lock_reserve(struct ring_buffer *buffer,
114 unsigned long length);
115int ring_buffer_unlock_commit(struct ring_buffer *buffer,
116 struct ring_buffer_event *event);
117int ring_buffer_write(struct ring_buffer *buffer,
118 unsigned long length, void *data);
119
120struct ring_buffer_event *
121ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts,
122 unsigned long *lost_events);
123struct ring_buffer_event *
124ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts,
125 unsigned long *lost_events);
126
127struct ring_buffer_iter *
128ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu);
129void ring_buffer_read_prepare_sync(void);
130void ring_buffer_read_start(struct ring_buffer_iter *iter);
131void ring_buffer_read_finish(struct ring_buffer_iter *iter);
132
133struct ring_buffer_event *
134ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts);
135struct ring_buffer_event *
136ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts);
137void ring_buffer_iter_reset(struct ring_buffer_iter *iter);
138int ring_buffer_iter_empty(struct ring_buffer_iter *iter);
139
140unsigned long ring_buffer_size(struct ring_buffer *buffer, int cpu);
141
142void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu);
143void ring_buffer_reset(struct ring_buffer *buffer);
144
145#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
146int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
147 struct ring_buffer *buffer_b, int cpu);
148#else
149static inline int
150ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
151 struct ring_buffer *buffer_b, int cpu)
152{
153 return -ENODEV;
154}
155#endif
156
157int ring_buffer_empty(struct ring_buffer *buffer);
158int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu);
159
160void ring_buffer_record_disable(struct ring_buffer *buffer);
161void ring_buffer_record_enable(struct ring_buffer *buffer);
162void ring_buffer_record_off(struct ring_buffer *buffer);
163void ring_buffer_record_on(struct ring_buffer *buffer);
164int ring_buffer_record_is_on(struct ring_buffer *buffer);
165void ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu);
166void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu);
167
168u64 ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu);
169unsigned long ring_buffer_bytes_cpu(struct ring_buffer *buffer, int cpu);
170unsigned long ring_buffer_entries(struct ring_buffer *buffer);
171unsigned long ring_buffer_overruns(struct ring_buffer *buffer);
172unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu);
173unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu);
174unsigned long ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu);
175unsigned long ring_buffer_dropped_events_cpu(struct ring_buffer *buffer, int cpu);
176unsigned long ring_buffer_read_events_cpu(struct ring_buffer *buffer, int cpu);
177
178u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu);
179void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer,
180 int cpu, u64 *ts);
181void ring_buffer_set_clock(struct ring_buffer *buffer,
182 u64 (*clock)(void));
183
184size_t ring_buffer_page_len(void *page);
185
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187void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu);
188void ring_buffer_free_read_page(struct ring_buffer *buffer, void *data);
189int ring_buffer_read_page(struct ring_buffer *buffer, void **data_page,
190 size_t len, int cpu, int full);
191
192struct trace_seq;
193
194int ring_buffer_print_entry_header(struct trace_seq *s);
195int ring_buffer_print_page_header(struct trace_seq *s);
196
197enum ring_buffer_flags {
198 RB_FL_OVERWRITE = 1 << 0,
199};
200
201#endif
202