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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
7a8e76a3 SR |
2 | #ifndef _LINUX_RING_BUFFER_H |
3 | #define _LINUX_RING_BUFFER_H | |
4 | ||
5 | #include <linux/mm.h> | |
6 | #include <linux/seq_file.h> | |
15693458 | 7 | #include <linux/poll.h> |
7a8e76a3 | 8 | |
117c3920 VD |
9 | #include <uapi/linux/trace_mmap.h> |
10 | ||
13292494 | 11 | struct trace_buffer; |
7a8e76a3 SR |
12 | struct ring_buffer_iter; |
13 | ||
14 | /* | |
c3706f00 | 15 | * Don't refer to this struct directly, use functions below. |
7a8e76a3 SR |
16 | */ |
17 | struct ring_buffer_event { | |
334d4169 | 18 | u32 type_len:5, time_delta:27; |
1744a21d | 19 | |
7a8e76a3 SR |
20 | u32 array[]; |
21 | }; | |
22 | ||
23 | /** | |
24 | * enum ring_buffer_type - internal ring buffer types | |
25 | * | |
2d622719 TZ |
26 | * @RINGBUF_TYPE_PADDING: Left over page padding or discarded event |
27 | * If time_delta is 0: | |
28 | * array is ignored | |
29 | * size is variable depending on how much | |
7a8e76a3 | 30 | * padding is needed |
2d622719 | 31 | * If time_delta is non zero: |
334d4169 LJ |
32 | * array[0] holds the actual length |
33 | * size = 4 + length (bytes) | |
7a8e76a3 SR |
34 | * |
35 | * @RINGBUF_TYPE_TIME_EXTEND: Extend the time delta | |
36 | * array[0] = time delta (28 .. 59) | |
37 | * size = 8 bytes | |
38 | * | |
dc4e2801 TZ |
39 | * @RINGBUF_TYPE_TIME_STAMP: Absolute timestamp |
40 | * Same format as TIME_EXTEND except that the | |
41 | * value is an absolute timestamp, not a delta | |
42 | * event.time_delta contains bottom 27 bits | |
43 | * array[0] = top (28 .. 59) bits | |
44 | * size = 8 bytes | |
7a8e76a3 | 45 | * |
334d4169 LJ |
46 | * <= @RINGBUF_TYPE_DATA_TYPE_LEN_MAX: |
47 | * Data record | |
48 | * If type_len is zero: | |
7a8e76a3 | 49 | * array[0] holds the actual length |
361b73d5 | 50 | * array[1..(length+3)/4] holds data |
334d4169 | 51 | * size = 4 + length (bytes) |
7a8e76a3 | 52 | * else |
334d4169 | 53 | * length = type_len << 2 |
361b73d5 LJ |
54 | * array[0..(length+3)/4-1] holds data |
55 | * size = 4 + length (bytes) | |
7a8e76a3 SR |
56 | */ |
57 | enum ring_buffer_type { | |
334d4169 | 58 | RINGBUF_TYPE_DATA_TYPE_LEN_MAX = 28, |
7a8e76a3 SR |
59 | RINGBUF_TYPE_PADDING, |
60 | RINGBUF_TYPE_TIME_EXTEND, | |
7a8e76a3 | 61 | RINGBUF_TYPE_TIME_STAMP, |
7a8e76a3 SR |
62 | }; |
63 | ||
64 | unsigned ring_buffer_event_length(struct ring_buffer_event *event); | |
65 | void *ring_buffer_event_data(struct ring_buffer_event *event); | |
efe6196a SRV |
66 | u64 ring_buffer_event_time_stamp(struct trace_buffer *buffer, |
67 | struct ring_buffer_event *event); | |
7a8e76a3 | 68 | |
fa1b47dd SR |
69 | /* |
70 | * ring_buffer_discard_commit will remove an event that has not | |
a9235b54 | 71 | * been committed yet. If this is used, then ring_buffer_unlock_commit |
fa1b47dd SR |
72 | * must not be called on the discarded event. This function |
73 | * will try to remove the event from the ring buffer completely | |
74 | * if another event has not been written after it. | |
75 | * | |
76 | * Example use: | |
77 | * | |
78 | * if (some_condition) | |
79 | * ring_buffer_discard_commit(buffer, event); | |
80 | * else | |
81 | * ring_buffer_unlock_commit(buffer, event); | |
82 | */ | |
13292494 | 83 | void ring_buffer_discard_commit(struct trace_buffer *buffer, |
fa1b47dd SR |
84 | struct ring_buffer_event *event); |
85 | ||
7a8e76a3 SR |
86 | /* |
87 | * size is in bytes for each per CPU buffer. | |
88 | */ | |
13292494 | 89 | struct trace_buffer * |
1f8a6a10 PZ |
90 | __ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *key); |
91 | ||
be68d63a SRG |
92 | struct trace_buffer *__ring_buffer_alloc_range(unsigned long size, unsigned flags, |
93 | int order, unsigned long start, | |
94 | unsigned long range_size, | |
95 | struct lock_class_key *key); | |
96 | ||
7a1d1e4b SRG |
97 | bool ring_buffer_last_boot_delta(struct trace_buffer *buffer, long *text, |
98 | long *data); | |
99 | ||
1f8a6a10 PZ |
100 | /* |
101 | * Because the ring buffer is generic, if other users of the ring buffer get | |
102 | * traced by ftrace, it can produce lockdep warnings. We need to keep each | |
103 | * ring buffer's lock class separate. | |
104 | */ | |
105 | #define ring_buffer_alloc(size, flags) \ | |
106 | ({ \ | |
107 | static struct lock_class_key __key; \ | |
108 | __ring_buffer_alloc((size), (flags), &__key); \ | |
109 | }) | |
110 | ||
be68d63a SRG |
111 | /* |
112 | * Because the ring buffer is generic, if other users of the ring buffer get | |
113 | * traced by ftrace, it can produce lockdep warnings. We need to keep each | |
114 | * ring buffer's lock class separate. | |
115 | */ | |
116 | #define ring_buffer_alloc_range(size, flags, order, start, range_size) \ | |
117 | ({ \ | |
118 | static struct lock_class_key __key; \ | |
119 | __ring_buffer_alloc_range((size), (flags), (order), (start), \ | |
120 | (range_size), &__key); \ | |
121 | }) | |
122 | ||
7af9ded0 | 123 | typedef bool (*ring_buffer_cond_fn)(void *data); |
2aa043a5 SRG |
124 | int ring_buffer_wait(struct trace_buffer *buffer, int cpu, int full, |
125 | ring_buffer_cond_fn cond, void *data); | |
13292494 | 126 | __poll_t ring_buffer_poll_wait(struct trace_buffer *buffer, int cpu, |
42fb0a1e | 127 | struct file *filp, poll_table *poll_table, int full); |
7e9fbbb1 | 128 | void ring_buffer_wake_waiters(struct trace_buffer *buffer, int cpu); |
15693458 | 129 | |
438ced17 VN |
130 | #define RING_BUFFER_ALL_CPUS -1 |
131 | ||
13292494 | 132 | void ring_buffer_free(struct trace_buffer *buffer); |
7a8e76a3 | 133 | |
13292494 | 134 | int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size, int cpu); |
7a8e76a3 | 135 | |
13292494 | 136 | void ring_buffer_change_overwrite(struct trace_buffer *buffer, int val); |
750912fa | 137 | |
13292494 | 138 | struct ring_buffer_event *ring_buffer_lock_reserve(struct trace_buffer *buffer, |
0a987751 | 139 | unsigned long length); |
04aabc32 | 140 | int ring_buffer_unlock_commit(struct trace_buffer *buffer); |
13292494 | 141 | int ring_buffer_write(struct trace_buffer *buffer, |
7a8e76a3 SR |
142 | unsigned long length, void *data); |
143 | ||
13292494 SRV |
144 | void ring_buffer_nest_start(struct trace_buffer *buffer); |
145 | void ring_buffer_nest_end(struct trace_buffer *buffer); | |
8e012066 | 146 | |
7a8e76a3 | 147 | struct ring_buffer_event * |
13292494 | 148 | ring_buffer_peek(struct trace_buffer *buffer, int cpu, u64 *ts, |
66a8cb95 | 149 | unsigned long *lost_events); |
7a8e76a3 | 150 | struct ring_buffer_event * |
13292494 | 151 | ring_buffer_consume(struct trace_buffer *buffer, int cpu, u64 *ts, |
66a8cb95 | 152 | unsigned long *lost_events); |
7a8e76a3 SR |
153 | |
154 | struct ring_buffer_iter * | |
13292494 | 155 | ring_buffer_read_prepare(struct trace_buffer *buffer, int cpu, gfp_t flags); |
72c9ddfd DM |
156 | void ring_buffer_read_prepare_sync(void); |
157 | void ring_buffer_read_start(struct ring_buffer_iter *iter); | |
7a8e76a3 SR |
158 | void ring_buffer_read_finish(struct ring_buffer_iter *iter); |
159 | ||
160 | struct ring_buffer_event * | |
161 | ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts); | |
bc1a72af | 162 | void ring_buffer_iter_advance(struct ring_buffer_iter *iter); |
7a8e76a3 SR |
163 | void ring_buffer_iter_reset(struct ring_buffer_iter *iter); |
164 | int ring_buffer_iter_empty(struct ring_buffer_iter *iter); | |
c9b7a4a7 | 165 | bool ring_buffer_iter_dropped(struct ring_buffer_iter *iter); |
7a8e76a3 | 166 | |
13292494 | 167 | unsigned long ring_buffer_size(struct trace_buffer *buffer, int cpu); |
8ec90be7 | 168 | unsigned long ring_buffer_max_event_size(struct trace_buffer *buffer); |
7a8e76a3 | 169 | |
13292494 | 170 | void ring_buffer_reset_cpu(struct trace_buffer *buffer, int cpu); |
b23d7a5f | 171 | void ring_buffer_reset_online_cpus(struct trace_buffer *buffer); |
13292494 | 172 | void ring_buffer_reset(struct trace_buffer *buffer); |
7a8e76a3 | 173 | |
85bac32c | 174 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
13292494 SRV |
175 | int ring_buffer_swap_cpu(struct trace_buffer *buffer_a, |
176 | struct trace_buffer *buffer_b, int cpu); | |
85bac32c SR |
177 | #else |
178 | static inline int | |
13292494 SRV |
179 | ring_buffer_swap_cpu(struct trace_buffer *buffer_a, |
180 | struct trace_buffer *buffer_b, int cpu) | |
85bac32c SR |
181 | { |
182 | return -ENODEV; | |
183 | } | |
184 | #endif | |
7a8e76a3 | 185 | |
13292494 SRV |
186 | bool ring_buffer_empty(struct trace_buffer *buffer); |
187 | bool ring_buffer_empty_cpu(struct trace_buffer *buffer, int cpu); | |
188 | ||
189 | void ring_buffer_record_disable(struct trace_buffer *buffer); | |
190 | void ring_buffer_record_enable(struct trace_buffer *buffer); | |
191 | void ring_buffer_record_off(struct trace_buffer *buffer); | |
192 | void ring_buffer_record_on(struct trace_buffer *buffer); | |
193 | bool ring_buffer_record_is_on(struct trace_buffer *buffer); | |
194 | bool ring_buffer_record_is_set_on(struct trace_buffer *buffer); | |
195 | void ring_buffer_record_disable_cpu(struct trace_buffer *buffer, int cpu); | |
196 | void ring_buffer_record_enable_cpu(struct trace_buffer *buffer, int cpu); | |
197 | ||
198 | u64 ring_buffer_oldest_event_ts(struct trace_buffer *buffer, int cpu); | |
199 | unsigned long ring_buffer_bytes_cpu(struct trace_buffer *buffer, int cpu); | |
200 | unsigned long ring_buffer_entries(struct trace_buffer *buffer); | |
201 | unsigned long ring_buffer_overruns(struct trace_buffer *buffer); | |
202 | unsigned long ring_buffer_entries_cpu(struct trace_buffer *buffer, int cpu); | |
203 | unsigned long ring_buffer_overrun_cpu(struct trace_buffer *buffer, int cpu); | |
204 | unsigned long ring_buffer_commit_overrun_cpu(struct trace_buffer *buffer, int cpu); | |
205 | unsigned long ring_buffer_dropped_events_cpu(struct trace_buffer *buffer, int cpu); | |
206 | unsigned long ring_buffer_read_events_cpu(struct trace_buffer *buffer, int cpu); | |
207 | ||
f3ef7202 | 208 | u64 ring_buffer_time_stamp(struct trace_buffer *buffer); |
13292494 | 209 | void ring_buffer_normalize_time_stamp(struct trace_buffer *buffer, |
37886f6a | 210 | int cpu, u64 *ts); |
13292494 | 211 | void ring_buffer_set_clock(struct trace_buffer *buffer, |
37886f6a | 212 | u64 (*clock)(void)); |
13292494 SRV |
213 | void ring_buffer_set_time_stamp_abs(struct trace_buffer *buffer, bool abs); |
214 | bool ring_buffer_time_stamp_abs(struct trace_buffer *buffer); | |
7a8e76a3 | 215 | |
13292494 | 216 | size_t ring_buffer_nr_dirty_pages(struct trace_buffer *buffer, int cpu); |
ef7a4a16 | 217 | |
bce761d7 TSV |
218 | struct buffer_data_read_page; |
219 | struct buffer_data_read_page * | |
220 | ring_buffer_alloc_read_page(struct trace_buffer *buffer, int cpu); | |
221 | void ring_buffer_free_read_page(struct trace_buffer *buffer, int cpu, | |
222 | struct buffer_data_read_page *page); | |
223 | int ring_buffer_read_page(struct trace_buffer *buffer, | |
224 | struct buffer_data_read_page *data_page, | |
ef7a4a16 | 225 | size_t len, int cpu, int full); |
bce761d7 | 226 | void *ring_buffer_read_page_data(struct buffer_data_read_page *page); |
8789a9e7 | 227 | |
d1b182a8 SR |
228 | struct trace_seq; |
229 | ||
230 | int ring_buffer_print_entry_header(struct trace_seq *s); | |
139f8400 | 231 | int ring_buffer_print_page_header(struct trace_buffer *buffer, struct trace_seq *s); |
d1b182a8 | 232 | |
2808e31e TSV |
233 | int ring_buffer_subbuf_order_get(struct trace_buffer *buffer); |
234 | int ring_buffer_subbuf_order_set(struct trace_buffer *buffer, int order); | |
235 | int ring_buffer_subbuf_size_get(struct trace_buffer *buffer); | |
236 | ||
7a8e76a3 SR |
237 | enum ring_buffer_flags { |
238 | RB_FL_OVERWRITE = 1 << 0, | |
239 | }; | |
240 | ||
b32614c0 SAS |
241 | #ifdef CONFIG_RING_BUFFER |
242 | int trace_rb_cpu_prepare(unsigned int cpu, struct hlist_node *node); | |
243 | #else | |
244 | #define trace_rb_cpu_prepare NULL | |
245 | #endif | |
246 | ||
117c3920 VD |
247 | int ring_buffer_map(struct trace_buffer *buffer, int cpu, |
248 | struct vm_area_struct *vma); | |
249 | int ring_buffer_unmap(struct trace_buffer *buffer, int cpu); | |
250 | int ring_buffer_map_get_reader(struct trace_buffer *buffer, int cpu); | |
7a8e76a3 | 251 | #endif /* _LINUX_RING_BUFFER_H */ |