Implement LTTNG_UST_TRACEPOINT_LIST
[lttng-ust.git] / liblttng-ust / lttng-ust-abi.c
CommitLineData
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1/*
2 * lttng-ust-abi.c
3 *
4 * Copyright 2010-2011 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5 *
6 * LTTng UST ABI
7 *
8 * Mimic system calls for:
9 * - session creation, returns an object descriptor or failure.
10 * - channel creation, returns an object descriptor or failure.
11 * - Operates on a session object descriptor
12 * - Takes all channel options as parameters.
13 * - stream get, returns an object descriptor or failure.
14 * - Operates on a channel object descriptor.
15 * - stream notifier get, returns an object descriptor or failure.
16 * - Operates on a channel object descriptor.
17 * - event creation, returns an object descriptor or failure.
18 * - Operates on a channel object descriptor
19 * - Takes an event name as parameter
20 * - Takes an instrumentation source as parameter
21 * - e.g. tracepoints, dynamic_probes...
22 * - Takes instrumentation source specific arguments.
23 *
24 * Dual LGPL v2.1/GPL v2 license.
25 */
26
4318ae1b 27#include <lttng/ust-abi.h>
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28#include <urcu/compiler.h>
29#include <urcu/list.h>
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30#include <lttng/ust-events.h>
31#include <lttng/usterr-signal-safe.h>
32#include "lttng/core.h"
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33#include "ltt-tracer.h"
34
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35static
36int lttng_abi_tracepoint_list(void);
37
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38/*
39 * Object descriptor table. Should be protected from concurrent access
40 * by the caller.
41 */
42
b61ce3b2 43struct lttng_ust_obj {
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44 union {
45 struct {
46 void *private_data;
b61ce3b2 47 const struct lttng_ust_objd_ops *ops;
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48 int f_count;
49 } s;
50 int freelist_next; /* offset freelist. end is -1. */
51 } u;
52};
53
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MD
54struct lttng_ust_objd_table {
55 struct lttng_ust_obj *array;
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56 unsigned int len, allocated_len;
57 int freelist_head; /* offset freelist head. end is -1 */
58};
59
b61ce3b2 60static struct lttng_ust_objd_table objd_table = {
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61 .freelist_head = -1,
62};
63
64static
b61ce3b2 65int objd_alloc(void *private_data, const struct lttng_ust_objd_ops *ops)
f4681817 66{
b61ce3b2 67 struct lttng_ust_obj *obj;
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68
69 if (objd_table.freelist_head != -1) {
70 obj = &objd_table.array[objd_table.freelist_head];
71 objd_table.freelist_head = obj->u.freelist_next;
72 goto end;
73 }
74
75 if (objd_table.len >= objd_table.allocated_len) {
76 unsigned int new_allocated_len, old_allocated_len;
b61ce3b2 77 struct lttng_ust_obj *new_table, *old_table;
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78
79 old_allocated_len = objd_table.allocated_len;
80 old_table = objd_table.array;
81 if (!old_allocated_len)
82 new_allocated_len = 1;
83 else
84 new_allocated_len = old_allocated_len << 1;
b61ce3b2 85 new_table = zmalloc(sizeof(struct lttng_ust_obj) * new_allocated_len);
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86 if (!new_table)
87 return -ENOMEM;
88 memcpy(new_table, old_table,
b61ce3b2 89 sizeof(struct lttng_ust_obj) * old_allocated_len);
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90 free(old_table);
91 objd_table.array = new_table;
92 objd_table.allocated_len = new_allocated_len;
93 }
94 obj = &objd_table.array[objd_table.len];
95 objd_table.len++;
96end:
97 obj->u.s.private_data = private_data;
98 obj->u.s.ops = ops;
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99 obj->u.s.f_count = 2; /* count == 1 : object is allocated */
100 /* count == 2 : allocated + hold ref */
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101 return obj - objd_table.array;
102}
103
104static
b61ce3b2 105struct lttng_ust_obj *_objd_get(int id)
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106{
107 if (id >= objd_table.len)
108 return NULL;
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109 if (!objd_table.array[id].u.s.f_count)
110 return NULL;
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111 return &objd_table.array[id];
112}
113
114static
115void *objd_private(int id)
116{
b61ce3b2 117 struct lttng_ust_obj *obj = _objd_get(id);
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118 assert(obj);
119 return obj->u.s.private_data;
120}
121
122static
123void objd_set_private(int id, void *private_data)
124{
b61ce3b2 125 struct lttng_ust_obj *obj = _objd_get(id);
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126 assert(obj);
127 obj->u.s.private_data = private_data;
128}
129
b61ce3b2 130const struct lttng_ust_objd_ops *objd_ops(int id)
f4681817 131{
b61ce3b2 132 struct lttng_ust_obj *obj = _objd_get(id);
46050b1a 133
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134 if (!obj)
135 return NULL;
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136 return obj->u.s.ops;
137}
138
139static
140void objd_free(int id)
141{
b61ce3b2 142 struct lttng_ust_obj *obj = _objd_get(id);
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143
144 assert(obj);
145 obj->u.freelist_next = objd_table.freelist_head;
146 objd_table.freelist_head = obj - objd_table.array;
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147 assert(obj->u.s.f_count == 1);
148 obj->u.s.f_count = 0; /* deallocated */
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149}
150
151static
152void objd_ref(int id)
153{
b61ce3b2 154 struct lttng_ust_obj *obj = _objd_get(id);
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155 obj->u.s.f_count++;
156}
157
d4419b81 158int lttng_ust_objd_unref(int id)
f4681817 159{
b61ce3b2 160 struct lttng_ust_obj *obj = _objd_get(id);
f4681817 161
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162 if (!obj)
163 return -EINVAL;
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164 if (obj->u.s.f_count == 1) {
165 ERR("Reference counting error\n");
166 return -EINVAL;
167 }
168 if ((--obj->u.s.f_count) == 1) {
b61ce3b2 169 const struct lttng_ust_objd_ops *ops = objd_ops(id);
a4be8962 170
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171 if (ops->release)
172 ops->release(id);
173 objd_free(id);
174 }
1ea11eab 175 return 0;
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176}
177
178static
179void objd_table_destroy(void)
180{
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181 int i;
182
fb50c39d 183 for (i = 0; i < objd_table.allocated_len; i++)
d4419b81 184 (void) lttng_ust_objd_unref(i);
f4681817 185 free(objd_table.array);
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186 objd_table.array = NULL;
187 objd_table.len = 0;
188 objd_table.allocated_len = 0;
17dfb34b 189 objd_table.freelist_head = -1;
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190}
191
192/*
193 * This is LTTng's own personal way to create an ABI for sessiond.
194 * We send commands over a socket.
195 */
196
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197static const struct lttng_ust_objd_ops lttng_ops;
198static const struct lttng_ust_objd_ops lttng_session_ops;
199static const struct lttng_ust_objd_ops lttng_channel_ops;
200static const struct lttng_ust_objd_ops lttng_metadata_ops;
201static const struct lttng_ust_objd_ops lttng_event_ops;
202static const struct lttng_ust_objd_ops lib_ring_buffer_objd_ops;
51489cad 203static const struct lttng_ust_objd_ops lttng_tracepoint_list_ops;
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204
205enum channel_type {
206 PER_CPU_CHANNEL,
207 METADATA_CHANNEL,
208};
209
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210int lttng_abi_create_root_handle(void)
211{
212 int root_handle;
213
214 root_handle = objd_alloc(NULL, &lttng_ops);
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215 return root_handle;
216}
217
818173b9 218static
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219int lttng_abi_create_session(void)
220{
221 struct ltt_session *session;
222 int session_objd, ret;
223
224 session = ltt_session_create();
225 if (!session)
226 return -ENOMEM;
227 session_objd = objd_alloc(session, &lttng_session_ops);
228 if (session_objd < 0) {
229 ret = session_objd;
230 goto objd_error;
231 }
232 session->objd = session_objd;
233 return session_objd;
234
235objd_error:
236 ltt_session_destroy(session);
237 return ret;
238}
239
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240static
241long lttng_abi_tracer_version(int objd,
242 struct lttng_ust_tracer_version *v)
243{
244 v->version = LTTNG_UST_VERSION;
245 v->patchlevel = LTTNG_UST_PATCHLEVEL;
246 v->sublevel = LTTNG_UST_SUBLEVEL;
247 return 0;
248}
249
250static
251long lttng_abi_add_context(int objd,
252 struct lttng_ust_context *context_param,
253 struct lttng_ctx **ctx, struct ltt_session *session)
254{
255 if (session->been_active)
256 return -EPERM;
257
258 switch (context_param->ctx) {
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259 case LTTNG_UST_CONTEXT_PTHREAD_ID:
260 return lttng_add_pthread_id_to_ctx(ctx);
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261 case LTTNG_UST_CONTEXT_VTID:
262 return lttng_add_vtid_to_ctx(ctx);
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263 case LTTNG_UST_CONTEXT_VPID:
264 return lttng_add_vpid_to_ctx(ctx);
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265 case LTTNG_UST_CONTEXT_PROCNAME:
266 return lttng_add_procname_to_ctx(ctx);
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267 default:
268 return -EINVAL;
269 }
270}
271
272/**
273 * lttng_cmd - lttng control through socket commands
274 *
275 * @objd: the object descriptor
276 * @cmd: the command
277 * @arg: command arg
278 *
279 * This descriptor implements lttng commands:
280 * LTTNG_UST_SESSION
281 * Returns a LTTng trace session object descriptor
282 * LTTNG_UST_TRACER_VERSION
283 * Returns the LTTng kernel tracer version
284 * LTTNG_UST_TRACEPOINT_LIST
285 * Returns a file descriptor listing available tracepoints
286 * LTTNG_UST_WAIT_QUIESCENT
287 * Returns after all previously running probes have completed
288 *
289 * The returned session will be deleted when its file descriptor is closed.
290 */
291static
292long lttng_cmd(int objd, unsigned int cmd, unsigned long arg)
293{
294 switch (cmd) {
295 case LTTNG_UST_SESSION:
296 return lttng_abi_create_session();
297 case LTTNG_UST_TRACER_VERSION:
298 return lttng_abi_tracer_version(objd,
299 (struct lttng_ust_tracer_version *) arg);
300 case LTTNG_UST_TRACEPOINT_LIST:
51489cad 301 return lttng_abi_tracepoint_list();
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302 case LTTNG_UST_WAIT_QUIESCENT:
303 synchronize_trace();
304 return 0;
305 default:
306 return -EINVAL;
307 }
308}
309
b61ce3b2 310static const struct lttng_ust_objd_ops lttng_ops = {
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311 .cmd = lttng_cmd,
312};
313
314/*
315 * We tolerate no failure in this function (if one happens, we print a dmesg
316 * error, but cannot return any error, because the channel information is
317 * invariant.
318 */
319static
320void lttng_metadata_create_events(int channel_objd)
321{
322 struct ltt_channel *channel = objd_private(channel_objd);
323 static struct lttng_ust_event metadata_params = {
324 .instrumentation = LTTNG_UST_TRACEPOINT,
325 .name = "lttng_metadata",
326 };
327 struct ltt_event *event;
328 int ret;
329
330 /*
331 * We tolerate no failure path after event creation. It will stay
332 * invariant for the rest of the session.
333 */
334 event = ltt_event_create(channel, &metadata_params, NULL);
335 if (!event) {
336 ret = -EINVAL;
337 goto create_error;
338 }
339 return;
340
341create_error:
342 WARN_ON(1);
343 return; /* not allowed to return error */
344}
345
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346int lttng_abi_create_channel(int session_objd,
347 struct lttng_ust_channel *chan_param,
348 enum channel_type channel_type)
349{
350 struct ltt_session *session = objd_private(session_objd);
b61ce3b2 351 const struct lttng_ust_objd_ops *ops;
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352 const char *transport_name;
353 struct ltt_channel *chan;
354 int chan_objd;
355 int ret = 0;
d028eddb 356 struct ltt_channel chan_priv_init;
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357
358 chan_objd = objd_alloc(NULL, &lttng_channel_ops);
359 if (chan_objd < 0) {
360 ret = chan_objd;
361 goto objd_error;
362 }
363 switch (channel_type) {
364 case PER_CPU_CHANNEL:
365 if (chan_param->output == LTTNG_UST_MMAP) {
366 transport_name = chan_param->overwrite ?
367 "relay-overwrite-mmap" : "relay-discard-mmap";
368 } else {
369 return -EINVAL;
370 }
371 ops = &lttng_channel_ops;
372 break;
373 case METADATA_CHANNEL:
374 if (chan_param->output == LTTNG_UST_MMAP)
375 transport_name = "relay-metadata-mmap";
376 else
377 return -EINVAL;
378 ops = &lttng_metadata_ops;
379 break;
380 default:
381 transport_name = "<unknown>";
382 break;
383 }
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384 memset(&chan_priv_init, 0, sizeof(chan_priv_init));
385 /* Copy of session UUID for consumer (availability through shm) */
386 memcpy(chan_priv_init.uuid, session->uuid, sizeof(session->uuid));
387
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388 /*
389 * We tolerate no failure path after channel creation. It will stay
390 * invariant for the rest of the session.
391 */
392 chan = ltt_channel_create(session, transport_name, NULL,
393 chan_param->subbuf_size,
394 chan_param->num_subbuf,
395 chan_param->switch_timer_interval,
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MD
396 chan_param->read_timer_interval,
397 &chan_param->shm_fd,
398 &chan_param->wait_fd,
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399 &chan_param->memory_map_size,
400 &chan_priv_init);
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401 if (!chan) {
402 ret = -EINVAL;
403 goto chan_error;
404 }
405 objd_set_private(chan_objd, chan);
406 chan->objd = chan_objd;
407 if (channel_type == METADATA_CHANNEL) {
408 session->metadata = chan;
409 lttng_metadata_create_events(chan_objd);
410 }
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411 /* The channel created holds a reference on the session */
412 objd_ref(session_objd);
413
414 return chan_objd;
415
416chan_error:
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417 {
418 int err;
419
d4419b81 420 err = lttng_ust_objd_unref(chan_objd);
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421 assert(!err);
422 }
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423objd_error:
424 return ret;
425}
426
427/**
428 * lttng_session_cmd - lttng session object command
429 *
430 * @obj: the object
431 * @cmd: the command
432 * @arg: command arg
433 *
434 * This descriptor implements lttng commands:
435 * LTTNG_UST_CHANNEL
436 * Returns a LTTng channel object descriptor
437 * LTTNG_UST_ENABLE
438 * Enables tracing for a session (weak enable)
439 * LTTNG_UST_DISABLE
440 * Disables tracing for a session (strong disable)
441 * LTTNG_UST_METADATA
442 * Returns a LTTng metadata object descriptor
443 *
444 * The returned channel will be deleted when its file descriptor is closed.
445 */
446static
447long lttng_session_cmd(int objd, unsigned int cmd, unsigned long arg)
448{
449 struct ltt_session *session = objd_private(objd);
450
451 switch (cmd) {
452 case LTTNG_UST_CHANNEL:
453 return lttng_abi_create_channel(objd,
454 (struct lttng_ust_channel *) arg,
455 PER_CPU_CHANNEL);
456 case LTTNG_UST_SESSION_START:
457 case LTTNG_UST_ENABLE:
458 return ltt_session_enable(session);
459 case LTTNG_UST_SESSION_STOP:
460 case LTTNG_UST_DISABLE:
461 return ltt_session_disable(session);
462 case LTTNG_UST_METADATA:
463 return lttng_abi_create_channel(objd,
464 (struct lttng_ust_channel *) arg,
465 METADATA_CHANNEL);
466 default:
467 return -EINVAL;
468 }
469}
470
471/*
472 * Called when the last file reference is dropped.
473 *
474 * Big fat note: channels and events are invariant for the whole session after
475 * their creation. So this session destruction also destroys all channel and
476 * event structures specific to this session (they are not destroyed when their
477 * individual file is released).
478 */
479static
1ea11eab 480int lttng_release_session(int objd)
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481{
482 struct ltt_session *session = objd_private(objd);
483
1ea11eab 484 if (session) {
f4681817 485 ltt_session_destroy(session);
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MD
486 return 0;
487 } else {
488 return -EINVAL;
489 }
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490}
491
b61ce3b2 492static const struct lttng_ust_objd_ops lttng_session_ops = {
1ea11eab 493 .release = lttng_release_session,
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494 .cmd = lttng_session_cmd,
495};
496
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497/*
498 * beware: we don't keep the mutex over the send, but we must walk the
499 * whole list each time we are called again. So sending one tracepoint
500 * at a time means this is O(n^2). TODO: do as in the kernel and send
501 * multiple tracepoints for each call to amortize this cost.
502 */
503static
504void ltt_tracepoint_list_get(struct ltt_tracepoint_list *list,
505 char *tp_list_entry)
506{
507 if (!list->got_first) {
508 tracepoint_iter_start(&list->iter);
509 list->got_first = 1;
510 goto copy;
511 }
512 tracepoint_iter_next(&list->iter);
513copy:
514 if (!list->iter.tracepoint) {
515 tp_list_entry[0] = '\0'; /* end of list */
516 } else {
517 memcpy(tp_list_entry, (*list->iter.tracepoint)->name,
518 LTTNG_UST_SYM_NAME_LEN);
519 }
520}
521
522static
523long lttng_tracepoint_list_cmd(int objd, unsigned int cmd, unsigned long arg)
524{
525 struct ltt_tracepoint_list *list = objd_private(objd);
526
527 switch (cmd) {
528 case LTTNG_UST_TRACEPOINT_LIST_GET:
529 ltt_tracepoint_list_get(list, (char *) arg);
530 return 0;
531 default:
532 return -EINVAL;
533 }
534}
535
536static
537int lttng_abi_tracepoint_list(void)
538{
539 int list_objd, ret;
540 struct ltt_tracepoint_list *list;
541
542 list_objd = objd_alloc(NULL, &lttng_tracepoint_list_ops);
543 if (list_objd < 0) {
544 ret = list_objd;
545 goto objd_error;
546 }
547 list = zmalloc(sizeof(*list));
548 if (!list) {
549 ret = -ENOMEM;
550 goto alloc_error;
551 }
552 objd_set_private(list_objd, list);
553
554 return list_objd;
555
556alloc_error:
557 {
558 int err;
559
560 err = lttng_ust_objd_unref(list_objd);
561 assert(!err);
562 }
563objd_error:
564 return ret;
565}
566
567static
568int lttng_release_tracepoint_list(int objd)
569{
570 struct ltt_tracepoint_list *list = objd_private(objd);
571
572 if (list) {
573 tracepoint_iter_stop(&list->iter);
574 free(list);
575 return 0;
576 } else {
577 return -EINVAL;
578 }
579}
580
581static const struct lttng_ust_objd_ops lttng_tracepoint_list_ops = {
582 .release = lttng_release_tracepoint_list,
583 .cmd = lttng_tracepoint_list_cmd,
584};
585
381c0f1e 586struct stream_priv_data {
4cfec15c 587 struct lttng_ust_lib_ring_buffer *buf;
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MD
588 struct ltt_channel *ltt_chan;
589};
590
f4681817 591static
381c0f1e 592int lttng_abi_open_stream(int channel_objd, struct lttng_ust_stream *info)
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MD
593{
594 struct ltt_channel *channel = objd_private(channel_objd);
4cfec15c 595 struct lttng_ust_lib_ring_buffer *buf;
381c0f1e 596 struct stream_priv_data *priv;
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597 int stream_objd, ret;
598
381c0f1e
MD
599 buf = channel->ops->buffer_read_open(channel->chan, channel->handle,
600 &info->shm_fd, &info->wait_fd, &info->memory_map_size);
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601 if (!buf)
602 return -ENOENT;
603
381c0f1e
MD
604 priv = zmalloc(sizeof(*priv));
605 if (!priv) {
606 ret = -ENOMEM;
607 goto alloc_error;
608 }
609 priv->buf = buf;
610 priv->ltt_chan = channel;
611 stream_objd = objd_alloc(priv, &lib_ring_buffer_objd_ops);
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MD
612 if (stream_objd < 0) {
613 ret = stream_objd;
614 goto objd_error;
615 }
381c0f1e
MD
616 /* Hold a reference on the channel object descriptor */
617 objd_ref(channel_objd);
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618 return stream_objd;
619
620objd_error:
381c0f1e
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621 free(priv);
622alloc_error:
623 channel->ops->buffer_read_close(buf, channel->handle);
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624 return ret;
625}
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626
627static
628int lttng_abi_create_event(int channel_objd,
629 struct lttng_ust_event *event_param)
630{
631 struct ltt_channel *channel = objd_private(channel_objd);
632 struct ltt_event *event;
633 int event_objd, ret;
634
635 event_param->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
636 event_objd = objd_alloc(NULL, &lttng_event_ops);
637 if (event_objd < 0) {
638 ret = event_objd;
639 goto objd_error;
640 }
641 /*
642 * We tolerate no failure path after event creation. It will stay
643 * invariant for the rest of the session.
644 */
645 event = ltt_event_create(channel, event_param, NULL);
646 if (!event) {
647 ret = -EINVAL;
648 goto event_error;
649 }
650 objd_set_private(event_objd, event);
651 /* The event holds a reference on the channel */
652 objd_ref(channel_objd);
653 return event_objd;
654
655event_error:
1ea11eab
MD
656 {
657 int err;
658
d4419b81 659 err = lttng_ust_objd_unref(event_objd);
1ea11eab
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660 assert(!err);
661 }
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662objd_error:
663 return ret;
664}
665
666/**
667 * lttng_channel_cmd - lttng control through object descriptors
668 *
669 * @objd: the object descriptor
670 * @cmd: the command
671 * @arg: command arg
672 *
673 * This object descriptor implements lttng commands:
674 * LTTNG_UST_STREAM
675 * Returns an event stream object descriptor or failure.
676 * (typically, one event stream records events from one CPU)
677 * LTTNG_UST_EVENT
678 * Returns an event object descriptor or failure.
679 * LTTNG_UST_CONTEXT
680 * Prepend a context field to each event in the channel
681 * LTTNG_UST_ENABLE
682 * Enable recording for events in this channel (weak enable)
683 * LTTNG_UST_DISABLE
684 * Disable recording for events in this channel (strong disable)
685 *
686 * Channel and event file descriptors also hold a reference on the session.
687 */
688static
689long lttng_channel_cmd(int objd, unsigned int cmd, unsigned long arg)
690{
691 struct ltt_channel *channel = objd_private(objd);
692
693 switch (cmd) {
694 case LTTNG_UST_STREAM:
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695 {
696 struct lttng_ust_stream *stream;
697
698 stream = (struct lttng_ust_stream *) arg;
699 /* stream used as output */
700 return lttng_abi_open_stream(objd, stream);
701 }
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702 case LTTNG_UST_EVENT:
703 return lttng_abi_create_event(objd, (struct lttng_ust_event *) arg);
704 case LTTNG_UST_CONTEXT:
705 return lttng_abi_add_context(objd,
706 (struct lttng_ust_context *) arg,
707 &channel->ctx, channel->session);
708 case LTTNG_UST_ENABLE:
709 return ltt_channel_enable(channel);
710 case LTTNG_UST_DISABLE:
711 return ltt_channel_disable(channel);
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712 case LTTNG_UST_FLUSH_BUFFER:
713 return channel->ops->flush_buffer(channel->chan, channel->handle);
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714 default:
715 return -EINVAL;
716 }
717}
718
719/**
720 * lttng_metadata_cmd - lttng control through object descriptors
721 *
722 * @objd: the object descriptor
723 * @cmd: the command
724 * @arg: command arg
725 *
726 * This object descriptor implements lttng commands:
727 * LTTNG_UST_STREAM
728 * Returns an event stream file descriptor or failure.
729 *
730 * Channel and event file descriptors also hold a reference on the session.
731 */
732static
733long lttng_metadata_cmd(int objd, unsigned int cmd, unsigned long arg)
734{
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735 struct ltt_channel *channel = objd_private(objd);
736
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737 switch (cmd) {
738 case LTTNG_UST_STREAM:
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739 {
740 struct lttng_ust_stream *stream;
741
742 stream = (struct lttng_ust_stream *) arg;
743 /* stream used as output */
744 return lttng_abi_open_stream(objd, stream);
745 }
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746 case LTTNG_UST_FLUSH_BUFFER:
747 return channel->ops->flush_buffer(channel->chan, channel->handle);
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748 default:
749 return -EINVAL;
750 }
751}
752
753#if 0
754/**
755 * lttng_channel_poll - lttng stream addition/removal monitoring
756 *
757 * @file: the file
758 * @wait: poll table
759 */
760unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
761{
762 struct ltt_channel *channel = file->private_data;
763 unsigned int mask = 0;
764
765 if (file->f_mode & FMODE_READ) {
766 poll_wait_set_exclusive(wait);
767 poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
768 wait);
769
770 if (channel->ops->is_disabled(channel->chan))
771 return POLLERR;
772 if (channel->ops->is_finalized(channel->chan))
773 return POLLHUP;
774 if (channel->ops->buffer_has_read_closed_stream(channel->chan))
775 return POLLIN | POLLRDNORM;
776 return 0;
777 }
778 return mask;
779
780}
781#endif //0
782
783static
784int lttng_channel_release(int objd)
785{
786 struct ltt_channel *channel = objd_private(objd);
787
788 if (channel)
d4419b81 789 return lttng_ust_objd_unref(channel->session->objd);
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790 return 0;
791}
792
b61ce3b2 793static const struct lttng_ust_objd_ops lttng_channel_ops = {
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794 .release = lttng_channel_release,
795 //.poll = lttng_channel_poll,
796 .cmd = lttng_channel_cmd,
797};
798
b61ce3b2 799static const struct lttng_ust_objd_ops lttng_metadata_ops = {
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800 .release = lttng_channel_release,
801 .cmd = lttng_metadata_cmd,
802};
803
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804/**
805 * lttng_rb_cmd - lttng ring buffer control through object descriptors
806 *
807 * @objd: the object descriptor
808 * @cmd: the command
809 * @arg: command arg
810 *
811 * This object descriptor implements lttng commands:
812 * (None for now. Access is done directly though shm.)
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813 */
814static
815long lttng_rb_cmd(int objd, unsigned int cmd, unsigned long arg)
816{
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817 switch (cmd) {
818 default:
819 return -EINVAL;
820 }
821}
822
823static
824int lttng_rb_release(int objd)
825{
826 struct stream_priv_data *priv = objd_private(objd);
4cfec15c 827 struct lttng_ust_lib_ring_buffer *buf;
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828 struct ltt_channel *channel;
829
830 if (priv) {
831 buf = priv->buf;
832 channel = priv->ltt_chan;
833 free(priv);
824f40b8 834 channel->ops->buffer_read_close(buf, channel->handle);
381c0f1e 835
d4419b81 836 return lttng_ust_objd_unref(channel->objd);
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837 }
838 return 0;
839}
840
b61ce3b2 841static const struct lttng_ust_objd_ops lib_ring_buffer_objd_ops = {
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842 .release = lttng_rb_release,
843 .cmd = lttng_rb_cmd,
844};
845
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846/**
847 * lttng_event_cmd - lttng control through object descriptors
848 *
849 * @objd: the object descriptor
850 * @cmd: the command
851 * @arg: command arg
852 *
853 * This object descriptor implements lttng commands:
854 * LTTNG_UST_CONTEXT
855 * Prepend a context field to each record of this event
856 * LTTNG_UST_ENABLE
857 * Enable recording for this event (weak enable)
858 * LTTNG_UST_DISABLE
859 * Disable recording for this event (strong disable)
860 */
861static
862long lttng_event_cmd(int objd, unsigned int cmd, unsigned long arg)
863{
864 struct ltt_event *event = objd_private(objd);
865
866 switch (cmd) {
867 case LTTNG_UST_CONTEXT:
868 return lttng_abi_add_context(objd,
869 (struct lttng_ust_context *) arg,
870 &event->ctx, event->chan->session);
871 case LTTNG_UST_ENABLE:
872 return ltt_event_enable(event);
873 case LTTNG_UST_DISABLE:
874 return ltt_event_disable(event);
875 default:
876 return -EINVAL;
877 }
878}
879
880static
881int lttng_event_release(int objd)
882{
883 struct ltt_event *event = objd_private(objd);
884
885 if (event)
d4419b81 886 return lttng_ust_objd_unref(event->chan->objd);
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887 return 0;
888}
889
890/* TODO: filter control ioctl */
b61ce3b2 891static const struct lttng_ust_objd_ops lttng_event_ops = {
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892 .release = lttng_event_release,
893 .cmd = lttng_event_cmd,
894};
895
b35d179d 896void lttng_ust_abi_exit(void)
f4681817 897{
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898 objd_table_destroy();
899}
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