1
2#ifndef _LINUX_RING_BUFFER_H
3#define _LINUX_RING_BUFFER_H
4
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 u32 type_len:5, time_delta:27;
17
18 u32 array[];
19};
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55enum ring_buffer_type {
56 RINGBUF_TYPE_DATA_TYPE_LEN_MAX = 28,
57 RINGBUF_TYPE_PADDING,
58 RINGBUF_TYPE_TIME_EXTEND,
59 RINGBUF_TYPE_TIME_STAMP,
60};
61
62unsigned ring_buffer_event_length(struct ring_buffer_event *event);
63void *ring_buffer_event_data(struct ring_buffer_event *event);
64u64 ring_buffer_event_time_stamp(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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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
100int ring_buffer_wait(struct ring_buffer *buffer, int cpu, int full);
101__poll_t 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
120void ring_buffer_nest_start(struct ring_buffer *buffer);
121void ring_buffer_nest_end(struct ring_buffer *buffer);
122
123struct ring_buffer_event *
124ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts,
125 unsigned long *lost_events);
126struct ring_buffer_event *
127ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts,
128 unsigned long *lost_events);
129
130struct ring_buffer_iter *
131ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu, gfp_t flags);
132void ring_buffer_read_prepare_sync(void);
133void ring_buffer_read_start(struct ring_buffer_iter *iter);
134void ring_buffer_read_finish(struct ring_buffer_iter *iter);
135
136struct ring_buffer_event *
137ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts);
138struct ring_buffer_event *
139ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts);
140void ring_buffer_iter_reset(struct ring_buffer_iter *iter);
141int ring_buffer_iter_empty(struct ring_buffer_iter *iter);
142
143unsigned long ring_buffer_size(struct ring_buffer *buffer, int cpu);
144
145void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu);
146void ring_buffer_reset(struct ring_buffer *buffer);
147
148#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
149int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
150 struct ring_buffer *buffer_b, int cpu);
151#else
152static inline int
153ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
154 struct ring_buffer *buffer_b, int cpu)
155{
156 return -ENODEV;
157}
158#endif
159
160bool ring_buffer_empty(struct ring_buffer *buffer);
161bool ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu);
162
163void ring_buffer_record_disable(struct ring_buffer *buffer);
164void ring_buffer_record_enable(struct ring_buffer *buffer);
165void ring_buffer_record_off(struct ring_buffer *buffer);
166void ring_buffer_record_on(struct ring_buffer *buffer);
167bool ring_buffer_record_is_on(struct ring_buffer *buffer);
168bool ring_buffer_record_is_set_on(struct ring_buffer *buffer);
169void ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu);
170void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu);
171
172u64 ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu);
173unsigned long ring_buffer_bytes_cpu(struct ring_buffer *buffer, int cpu);
174unsigned long ring_buffer_entries(struct ring_buffer *buffer);
175unsigned long ring_buffer_overruns(struct ring_buffer *buffer);
176unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu);
177unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu);
178unsigned long ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu);
179unsigned long ring_buffer_dropped_events_cpu(struct ring_buffer *buffer, int cpu);
180unsigned long ring_buffer_read_events_cpu(struct ring_buffer *buffer, int cpu);
181
182u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu);
183void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer,
184 int cpu, u64 *ts);
185void ring_buffer_set_clock(struct ring_buffer *buffer,
186 u64 (*clock)(void));
187void ring_buffer_set_time_stamp_abs(struct ring_buffer *buffer, bool abs);
188bool ring_buffer_time_stamp_abs(struct ring_buffer *buffer);
189
190size_t ring_buffer_nr_pages(struct ring_buffer *buffer, int cpu);
191size_t ring_buffer_nr_dirty_pages(struct ring_buffer *buffer, int cpu);
192
193void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu);
194void ring_buffer_free_read_page(struct ring_buffer *buffer, int cpu, void *data);
195int ring_buffer_read_page(struct ring_buffer *buffer, void **data_page,
196 size_t len, int cpu, int full);
197
198struct trace_seq;
199
200int ring_buffer_print_entry_header(struct trace_seq *s);
201int ring_buffer_print_page_header(struct trace_seq *s);
202
203enum ring_buffer_flags {
204 RB_FL_OVERWRITE = 1 << 0,
205};
206
207#ifdef CONFIG_RING_BUFFER
208int trace_rb_cpu_prepare(unsigned int cpu, struct hlist_node *node);
209#else
210#define trace_rb_cpu_prepare NULL
211#endif
212
213#endif
214