Commit | Line | Data |
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881833e3 | 1 | /* |
a90917c3 | 2 | * lttng-ring-buffer-client.h |
881833e3 | 3 | * |
881833e3 MD |
4 | * LTTng lib ring buffer client template. |
5 | * | |
886d51a3 MD |
6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
7 | * | |
8 | * This library is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; only | |
11 | * version 2.1 of the License. | |
12 | * | |
13 | * This library is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | * Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this library; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
881833e3 MD |
21 | */ |
22 | ||
23 | #include <linux/module.h> | |
24 | #include <linux/types.h> | |
25 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ | |
a90917c3 MD |
26 | #include "lttng-events.h" |
27 | #include "lttng-tracer.h" | |
881833e3 | 28 | |
dd5a0db3 MD |
29 | static struct lttng_transport lttng_relay_transport; |
30 | ||
881833e3 MD |
31 | struct metadata_packet_header { |
32 | uint32_t magic; /* 0x75D11D57 */ | |
1ec3f75a | 33 | uint8_t uuid[16]; /* Unique Universal Identifier */ |
881833e3 MD |
34 | uint32_t checksum; /* 0 if unused */ |
35 | uint32_t content_size; /* in bits */ | |
36 | uint32_t packet_size; /* in bits */ | |
37 | uint8_t compression_scheme; /* 0 if unused */ | |
38 | uint8_t encryption_scheme; /* 0 if unused */ | |
39 | uint8_t checksum_scheme; /* 0 if unused */ | |
4173df96 MD |
40 | uint8_t major; /* CTF spec major version number */ |
41 | uint8_t minor; /* CTF spec minor version number */ | |
881833e3 MD |
42 | uint8_t header_end[0]; |
43 | }; | |
44 | ||
45 | struct metadata_record_header { | |
46 | uint8_t header_end[0]; /* End of header */ | |
47 | }; | |
48 | ||
49 | static const struct lib_ring_buffer_config client_config; | |
50 | ||
51 | static inline | |
52 | u64 lib_ring_buffer_clock_read(struct channel *chan) | |
53 | { | |
54 | return 0; | |
55 | } | |
56 | ||
57 | static inline | |
58 | unsigned char record_header_size(const struct lib_ring_buffer_config *config, | |
59 | struct channel *chan, size_t offset, | |
64c796d8 | 60 | size_t *pre_header_padding, |
881833e3 MD |
61 | struct lib_ring_buffer_ctx *ctx) |
62 | { | |
63 | return 0; | |
64 | } | |
65 | ||
66 | #include "wrapper/ringbuffer/api.h" | |
67 | ||
68 | static u64 client_ring_buffer_clock_read(struct channel *chan) | |
69 | { | |
70 | return 0; | |
71 | } | |
72 | ||
73 | static | |
74 | size_t client_record_header_size(const struct lib_ring_buffer_config *config, | |
75 | struct channel *chan, size_t offset, | |
881833e3 | 76 | size_t *pre_header_padding, |
881833e3 MD |
77 | struct lib_ring_buffer_ctx *ctx) |
78 | { | |
79 | return 0; | |
80 | } | |
81 | ||
82 | /** | |
83 | * client_packet_header_size - called on buffer-switch to a new sub-buffer | |
84 | * | |
85 | * Return header size without padding after the structure. Don't use packed | |
86 | * structure because gcc generates inefficient code on some architectures | |
87 | * (powerpc, mips..) | |
88 | */ | |
89 | static size_t client_packet_header_size(void) | |
90 | { | |
91 | return offsetof(struct metadata_packet_header, header_end); | |
92 | } | |
93 | ||
94 | static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc, | |
95 | unsigned int subbuf_idx) | |
96 | { | |
97 | struct channel *chan = buf->backend.chan; | |
98 | struct metadata_packet_header *header = | |
99 | (struct metadata_packet_header *) | |
100 | lib_ring_buffer_offset_address(&buf->backend, | |
101 | subbuf_idx * chan->backend.subbuf_size); | |
a90917c3 MD |
102 | struct lttng_channel *lttng_chan = channel_get_private(chan); |
103 | struct lttng_session *session = lttng_chan->session; | |
881833e3 MD |
104 | |
105 | header->magic = TSDL_MAGIC_NUMBER; | |
1ec3f75a | 106 | memcpy(header->uuid, session->uuid.b, sizeof(session->uuid)); |
881833e3 MD |
107 | header->checksum = 0; /* 0 if unused */ |
108 | header->content_size = 0xFFFFFFFF; /* in bits, for debugging */ | |
109 | header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */ | |
110 | header->compression_scheme = 0; /* 0 if unused */ | |
111 | header->encryption_scheme = 0; /* 0 if unused */ | |
112 | header->checksum_scheme = 0; /* 0 if unused */ | |
4173df96 MD |
113 | header->major = CTF_SPEC_MAJOR; |
114 | header->minor = CTF_SPEC_MINOR; | |
881833e3 MD |
115 | } |
116 | ||
117 | /* | |
118 | * offset is assumed to never be 0 here : never deliver a completely empty | |
119 | * subbuffer. data_size is between 1 and subbuf_size. | |
120 | */ | |
121 | static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc, | |
122 | unsigned int subbuf_idx, unsigned long data_size) | |
123 | { | |
124 | struct channel *chan = buf->backend.chan; | |
d793d5e1 | 125 | struct metadata_packet_header *header = |
1ec3f75a | 126 | (struct metadata_packet_header *) |
881833e3 MD |
127 | lib_ring_buffer_offset_address(&buf->backend, |
128 | subbuf_idx * chan->backend.subbuf_size); | |
129 | unsigned long records_lost = 0; | |
130 | ||
131 | header->content_size = data_size * CHAR_BIT; /* in bits */ | |
132 | header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */ | |
71c1d843 MD |
133 | /* |
134 | * We do not care about the records lost count, because the metadata | |
135 | * channel waits and retry. | |
136 | */ | |
137 | (void) lib_ring_buffer_get_records_lost_full(&client_config, buf); | |
881833e3 MD |
138 | records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf); |
139 | records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf); | |
140 | WARN_ON_ONCE(records_lost != 0); | |
141 | } | |
142 | ||
143 | static int client_buffer_create(struct lib_ring_buffer *buf, void *priv, | |
144 | int cpu, const char *name) | |
145 | { | |
146 | return 0; | |
147 | } | |
148 | ||
149 | static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu) | |
150 | { | |
151 | } | |
152 | ||
3b731ab1 JD |
153 | static int client_timestamp_begin(const struct lib_ring_buffer_config *config, |
154 | struct lib_ring_buffer *buf, uint64_t *timestamp_begin) | |
155 | { | |
156 | return -ENOSYS; | |
157 | } | |
158 | ||
159 | static int client_timestamp_end(const struct lib_ring_buffer_config *config, | |
160 | struct lib_ring_buffer *bufb, | |
161 | uint64_t *timestamp_end) | |
162 | { | |
163 | return -ENOSYS; | |
164 | } | |
165 | ||
166 | static int client_events_discarded(const struct lib_ring_buffer_config *config, | |
167 | struct lib_ring_buffer *bufb, | |
168 | uint64_t *events_discarded) | |
169 | { | |
170 | return -ENOSYS; | |
171 | } | |
172 | ||
2348ca17 JD |
173 | static int client_current_timestamp(const struct lib_ring_buffer_config *config, |
174 | struct lib_ring_buffer *bufb, | |
175 | uint64_t *ts) | |
176 | { | |
177 | return -ENOSYS; | |
178 | } | |
179 | ||
3b731ab1 JD |
180 | static int client_content_size(const struct lib_ring_buffer_config *config, |
181 | struct lib_ring_buffer *bufb, | |
182 | uint64_t *content_size) | |
183 | { | |
184 | return -ENOSYS; | |
185 | } | |
186 | ||
187 | static int client_packet_size(const struct lib_ring_buffer_config *config, | |
188 | struct lib_ring_buffer *bufb, | |
189 | uint64_t *packet_size) | |
190 | { | |
191 | return -ENOSYS; | |
192 | } | |
193 | ||
194 | static int client_stream_id(const struct lib_ring_buffer_config *config, | |
195 | struct lib_ring_buffer *bufb, | |
196 | uint64_t *stream_id) | |
197 | { | |
198 | return -ENOSYS; | |
199 | } | |
200 | ||
881833e3 MD |
201 | static const struct lib_ring_buffer_config client_config = { |
202 | .cb.ring_buffer_clock_read = client_ring_buffer_clock_read, | |
203 | .cb.record_header_size = client_record_header_size, | |
204 | .cb.subbuffer_header_size = client_packet_header_size, | |
205 | .cb.buffer_begin = client_buffer_begin, | |
206 | .cb.buffer_end = client_buffer_end, | |
207 | .cb.buffer_create = client_buffer_create, | |
208 | .cb.buffer_finalize = client_buffer_finalize, | |
209 | ||
210 | .tsc_bits = 0, | |
211 | .alloc = RING_BUFFER_ALLOC_GLOBAL, | |
212 | .sync = RING_BUFFER_SYNC_GLOBAL, | |
213 | .mode = RING_BUFFER_MODE_TEMPLATE, | |
214 | .backend = RING_BUFFER_PAGE, | |
2db1399a | 215 | .output = RING_BUFFER_OUTPUT_TEMPLATE, |
881833e3 MD |
216 | .oops = RING_BUFFER_OOPS_CONSISTENCY, |
217 | .ipi = RING_BUFFER_IPI_BARRIER, | |
218 | .wakeup = RING_BUFFER_WAKEUP_BY_TIMER, | |
219 | }; | |
220 | ||
dd5a0db3 MD |
221 | static |
222 | void release_priv_ops(void *priv_ops) | |
223 | { | |
224 | module_put(THIS_MODULE); | |
225 | } | |
226 | ||
227 | static | |
228 | void lttng_channel_destroy(struct channel *chan) | |
229 | { | |
230 | channel_destroy(chan); | |
231 | } | |
232 | ||
881833e3 MD |
233 | static |
234 | struct channel *_channel_create(const char *name, | |
a90917c3 | 235 | struct lttng_channel *lttng_chan, void *buf_addr, |
881833e3 MD |
236 | size_t subbuf_size, size_t num_subbuf, |
237 | unsigned int switch_timer_interval, | |
238 | unsigned int read_timer_interval) | |
239 | { | |
dd5a0db3 MD |
240 | struct channel *chan; |
241 | ||
242 | chan = channel_create(&client_config, name, lttng_chan, buf_addr, | |
881833e3 MD |
243 | subbuf_size, num_subbuf, switch_timer_interval, |
244 | read_timer_interval); | |
dd5a0db3 MD |
245 | if (chan) { |
246 | /* | |
247 | * Ensure this module is not unloaded before we finish | |
248 | * using lttng_relay_transport.ops. | |
249 | */ | |
250 | if (!try_module_get(THIS_MODULE)) { | |
251 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); | |
252 | goto error; | |
253 | } | |
254 | chan->backend.priv_ops = <tng_relay_transport.ops; | |
255 | chan->backend.release_priv_ops = release_priv_ops; | |
256 | } | |
257 | return chan; | |
881833e3 | 258 | |
dd5a0db3 MD |
259 | error: |
260 | lttng_channel_destroy(chan); | |
261 | return NULL; | |
881833e3 MD |
262 | } |
263 | ||
264 | static | |
a90917c3 | 265 | struct lib_ring_buffer *lttng_buffer_read_open(struct channel *chan) |
881833e3 MD |
266 | { |
267 | struct lib_ring_buffer *buf; | |
881833e3 | 268 | |
cd4bd11f MD |
269 | buf = channel_get_ring_buffer(&client_config, chan, 0); |
270 | if (!lib_ring_buffer_open_read(buf)) | |
271 | return buf; | |
881833e3 MD |
272 | return NULL; |
273 | } | |
274 | ||
f71ecafa | 275 | static |
a90917c3 | 276 | int lttng_buffer_has_read_closed_stream(struct channel *chan) |
f71ecafa MD |
277 | { |
278 | struct lib_ring_buffer *buf; | |
279 | int cpu; | |
280 | ||
281 | for_each_channel_cpu(cpu, chan) { | |
282 | buf = channel_get_ring_buffer(&client_config, chan, cpu); | |
283 | if (!atomic_long_read(&buf->active_readers)) | |
284 | return 1; | |
285 | } | |
286 | return 0; | |
287 | } | |
288 | ||
881833e3 | 289 | static |
a90917c3 | 290 | void lttng_buffer_read_close(struct lib_ring_buffer *buf) |
881833e3 MD |
291 | { |
292 | lib_ring_buffer_release_read(buf); | |
881833e3 MD |
293 | } |
294 | ||
c099397a | 295 | static |
a90917c3 | 296 | int lttng_event_reserve(struct lib_ring_buffer_ctx *ctx, uint32_t event_id) |
881833e3 MD |
297 | { |
298 | return lib_ring_buffer_reserve(&client_config, ctx); | |
299 | } | |
300 | ||
c099397a | 301 | static |
a90917c3 | 302 | void lttng_event_commit(struct lib_ring_buffer_ctx *ctx) |
881833e3 MD |
303 | { |
304 | lib_ring_buffer_commit(&client_config, ctx); | |
305 | } | |
306 | ||
c099397a | 307 | static |
a90917c3 | 308 | void lttng_event_write(struct lib_ring_buffer_ctx *ctx, const void *src, |
881833e3 MD |
309 | size_t len) |
310 | { | |
311 | lib_ring_buffer_write(&client_config, ctx, src, len); | |
312 | } | |
313 | ||
4ea00e4f | 314 | static |
a90917c3 | 315 | void lttng_event_write_from_user(struct lib_ring_buffer_ctx *ctx, |
4ea00e4f JD |
316 | const void __user *src, size_t len) |
317 | { | |
7b8ea3a5 | 318 | lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len); |
4ea00e4f JD |
319 | } |
320 | ||
58aa5d24 | 321 | static |
a90917c3 | 322 | void lttng_event_memset(struct lib_ring_buffer_ctx *ctx, |
58aa5d24 MD |
323 | int c, size_t len) |
324 | { | |
325 | lib_ring_buffer_memset(&client_config, ctx, c, len); | |
326 | } | |
327 | ||
16f78f3a MD |
328 | static |
329 | void lttng_event_strcpy(struct lib_ring_buffer_ctx *ctx, const char *src, | |
330 | size_t len) | |
331 | { | |
332 | lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#'); | |
333 | } | |
334 | ||
1ec3f75a | 335 | static |
a90917c3 | 336 | size_t lttng_packet_avail_size(struct channel *chan) |
1ec3f75a MD |
337 | |
338 | { | |
339 | unsigned long o_begin; | |
340 | struct lib_ring_buffer *buf; | |
341 | ||
342 | buf = chan->backend.buf; /* Only for global buffer ! */ | |
343 | o_begin = v_read(&client_config, &buf->offset); | |
344 | if (subbuf_offset(o_begin, chan) != 0) { | |
345 | return chan->backend.subbuf_size - subbuf_offset(o_begin, chan); | |
346 | } else { | |
347 | return chan->backend.subbuf_size - subbuf_offset(o_begin, chan) | |
348 | - sizeof(struct metadata_packet_header); | |
349 | } | |
350 | } | |
351 | ||
c099397a | 352 | static |
a90917c3 | 353 | wait_queue_head_t *lttng_get_writer_buf_wait_queue(struct channel *chan, int cpu) |
c099397a | 354 | { |
71c1d843 MD |
355 | struct lib_ring_buffer *buf = channel_get_ring_buffer(&client_config, |
356 | chan, cpu); | |
357 | return &buf->write_wait; | |
24cedcfe MD |
358 | } |
359 | ||
360 | static | |
a90917c3 | 361 | wait_queue_head_t *lttng_get_hp_wait_queue(struct channel *chan) |
24cedcfe MD |
362 | { |
363 | return &chan->hp_wait; | |
364 | } | |
365 | ||
366 | static | |
a90917c3 | 367 | int lttng_is_finalized(struct channel *chan) |
24cedcfe MD |
368 | { |
369 | return lib_ring_buffer_channel_is_finalized(chan); | |
c099397a MD |
370 | } |
371 | ||
254ec7bc | 372 | static |
a90917c3 | 373 | int lttng_is_disabled(struct channel *chan) |
254ec7bc MD |
374 | { |
375 | return lib_ring_buffer_channel_is_disabled(chan); | |
376 | } | |
377 | ||
a90917c3 | 378 | static struct lttng_transport lttng_relay_transport = { |
881833e3 MD |
379 | .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING, |
380 | .owner = THIS_MODULE, | |
381 | .ops = { | |
382 | .channel_create = _channel_create, | |
a90917c3 MD |
383 | .channel_destroy = lttng_channel_destroy, |
384 | .buffer_read_open = lttng_buffer_read_open, | |
f71ecafa | 385 | .buffer_has_read_closed_stream = |
a90917c3 MD |
386 | lttng_buffer_has_read_closed_stream, |
387 | .buffer_read_close = lttng_buffer_read_close, | |
388 | .event_reserve = lttng_event_reserve, | |
389 | .event_commit = lttng_event_commit, | |
390 | .event_write_from_user = lttng_event_write_from_user, | |
391 | .event_memset = lttng_event_memset, | |
392 | .event_write = lttng_event_write, | |
16f78f3a | 393 | .event_strcpy = lttng_event_strcpy, |
a90917c3 MD |
394 | .packet_avail_size = lttng_packet_avail_size, |
395 | .get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue, | |
396 | .get_hp_wait_queue = lttng_get_hp_wait_queue, | |
397 | .is_finalized = lttng_is_finalized, | |
398 | .is_disabled = lttng_is_disabled, | |
67a80835 MD |
399 | .timestamp_begin = client_timestamp_begin, |
400 | .timestamp_end = client_timestamp_end, | |
401 | .events_discarded = client_events_discarded, | |
402 | .content_size = client_content_size, | |
403 | .packet_size = client_packet_size, | |
404 | .stream_id = client_stream_id, | |
405 | .current_timestamp = client_current_timestamp, | |
881833e3 MD |
406 | }, |
407 | }; | |
408 | ||
a90917c3 | 409 | static int __init lttng_ring_buffer_client_init(void) |
881833e3 MD |
410 | { |
411 | /* | |
412 | * This vmalloc sync all also takes care of the lib ring buffer | |
413 | * vmalloc'd module pages when it is built as a module into LTTng. | |
414 | */ | |
415 | wrapper_vmalloc_sync_all(); | |
a90917c3 | 416 | lttng_transport_register(<tng_relay_transport); |
881833e3 MD |
417 | return 0; |
418 | } | |
419 | ||
a90917c3 | 420 | module_init(lttng_ring_buffer_client_init); |
881833e3 | 421 | |
a90917c3 | 422 | static void __exit lttng_ring_buffer_client_exit(void) |
881833e3 | 423 | { |
a90917c3 | 424 | lttng_transport_unregister(<tng_relay_transport); |
881833e3 MD |
425 | } |
426 | ||
a90917c3 | 427 | module_exit(lttng_ring_buffer_client_exit); |
881833e3 MD |
428 | |
429 | MODULE_LICENSE("GPL and additional rights"); | |
430 | MODULE_AUTHOR("Mathieu Desnoyers"); | |
431 | MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING | |
432 | " client"); |