2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License, version 2 only,
6 * as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 #include <urcu/list.h>
23 #include <lttng/lttng.h>
24 #include <common/error.h>
25 #include <common/sessiond-comm/sessiond-comm.h>
32 #include "trace-kernel.h"
33 #include "trace-ust.h"
36 * Add unique UST event based on the event name, filter bytecode and loglevel.
38 static void add_unique_ust_event(struct lttng_ht
*ht
,
39 struct ltt_ust_event
*event
)
41 struct cds_lfht_node
*node_ptr
;
42 struct ltt_ust_ht_key key
;
48 key
.name
= event
->attr
.name
;
49 key
.filter
= (struct lttng_filter_bytecode
*) event
->filter
;
50 key
.loglevel
= event
->attr
.loglevel
;
52 node_ptr
= cds_lfht_add_unique(ht
->ht
,
53 ht
->hash_fct(event
->node
.key
, lttng_ht_seed
),
54 trace_ust_ht_match_event
, &key
, &event
->node
.node
);
55 assert(node_ptr
== &event
->node
.node
);
59 * Setup a lttng_event used to enable *all* syscall tracing.
61 static void init_syscalls_kernel_event(struct lttng_event
*event
)
65 event
->name
[0] = '\0';
67 * We use LTTNG_EVENT* here since the trace kernel creation will make the
68 * right changes for the kernel.
70 event
->type
= LTTNG_EVENT_SYSCALL
;
74 * Disable kernel tracepoint event for a channel from the kernel session.
76 int event_kernel_disable_tracepoint(struct ltt_kernel_channel
*kchan
,
80 struct ltt_kernel_event
*kevent
;
84 kevent
= trace_kernel_get_event_by_name(event_name
, kchan
);
86 ret
= LTTNG_ERR_NO_EVENT
;
90 ret
= kernel_disable_event(kevent
);
92 ret
= LTTNG_ERR_KERN_DISABLE_FAIL
;
96 DBG("Kernel event %s disable for channel %s.",
97 kevent
->event
->name
, kchan
->channel
->name
);
106 * Disable kernel tracepoint events for a channel from the kernel session.
108 int event_kernel_disable_all_tracepoints(struct ltt_kernel_channel
*kchan
)
111 struct ltt_kernel_event
*kevent
;
115 /* For each event in the kernel session */
116 cds_list_for_each_entry(kevent
, &kchan
->events_list
.head
, list
) {
117 ret
= kernel_disable_event(kevent
);
119 /* We continue disabling the rest */
128 * Disable kernel syscall events for a channel from the kernel session.
130 int event_kernel_disable_all_syscalls(struct ltt_kernel_channel
*kchan
)
132 ERR("Cannot disable syscall tracing for existing session. Please destroy session instead.");
133 return LTTNG_OK
; /* Return OK so disable all succeeds */
137 * Disable all kernel event for a channel from the kernel session.
139 int event_kernel_disable_all(struct ltt_kernel_channel
*kchan
)
145 ret
= event_kernel_disable_all_tracepoints(kchan
);
148 ret
= event_kernel_disable_all_syscalls(kchan
);
153 * Enable kernel tracepoint event for a channel from the kernel session.
155 int event_kernel_enable_tracepoint(struct ltt_kernel_channel
*kchan
,
156 struct lttng_event
*event
)
159 struct ltt_kernel_event
*kevent
;
164 kevent
= trace_kernel_get_event_by_name(event
->name
, kchan
);
165 if (kevent
== NULL
) {
166 ret
= kernel_create_event(event
, kchan
);
170 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
173 ret
= LTTNG_ERR_KERN_EVENT_ENOSYS
;
176 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
181 } else if (kevent
->enabled
== 0) {
182 ret
= kernel_enable_event(kevent
);
184 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
188 /* At this point, the event is considered enabled */
189 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
199 * Enable all kernel tracepoint events of a channel of the kernel session.
201 int event_kernel_enable_all_tracepoints(struct ltt_kernel_channel
*kchan
,
202 int kernel_tracer_fd
)
205 struct ltt_kernel_event
*kevent
;
206 struct lttng_event
*event_list
= NULL
;
210 /* For each event in the kernel session */
211 cds_list_for_each_entry(kevent
, &kchan
->events_list
.head
, list
) {
212 if (kevent
->enabled
== 0) {
213 ret
= kernel_enable_event(kevent
);
215 /* Enable failed but still continue */
221 size
= kernel_list_events(kernel_tracer_fd
, &event_list
);
223 ret
= LTTNG_ERR_KERN_LIST_FAIL
;
227 for (i
= 0; i
< size
; i
++) {
228 kevent
= trace_kernel_get_event_by_name(event_list
[i
].name
, kchan
);
229 if (kevent
== NULL
) {
230 /* Default event type for enable all */
231 event_list
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
232 /* Enable each single tracepoint event */
233 ret
= kernel_create_event(&event_list
[i
], kchan
);
235 /* Ignore error here and continue */
247 * Enable all kernel tracepoint events of a channel of the kernel session.
249 int event_kernel_enable_all_syscalls(struct ltt_kernel_channel
*kchan
,
250 int kernel_tracer_fd
)
253 struct lttng_event event
;
257 init_syscalls_kernel_event(&event
);
259 DBG("Enabling all syscall tracing");
261 ret
= kernel_create_event(&event
, kchan
);
263 if (ret
== -EEXIST
) {
264 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
266 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
277 * Enable all kernel events of a channel of the kernel session.
279 int event_kernel_enable_all(struct ltt_kernel_channel
*kchan
,
280 int kernel_tracer_fd
)
286 tp_ret
= event_kernel_enable_all_tracepoints(kchan
, kernel_tracer_fd
);
287 if (tp_ret
!= LTTNG_OK
) {
292 * Reaching this code path means that all tracepoints were enabled without
293 * errors so we ignore the error value of syscalls.
295 * At the moment, failing to enable syscalls on "lttng enable-event -a -k"
296 * is not considered an error that need to be returned to the client since
297 * tracepoints did not fail. Future work will allow us to send back
298 * multiple errors to the client in one API call.
300 (void) event_kernel_enable_all_syscalls(kchan
, kernel_tracer_fd
);
307 * ============================
308 * UST : The Ultimate Frontier!
309 * ============================
313 * Enable all UST tracepoints for a channel from a UST session.
315 int event_ust_enable_all_tracepoints(struct ltt_ust_session
*usess
,
316 struct ltt_ust_channel
*uchan
, struct lttng_filter_bytecode
*filter
)
319 struct lttng_ht_iter iter
;
320 struct ltt_ust_event
*uevent
= NULL
;
321 struct lttng_event
*events
= NULL
;
328 /* Enable existing events */
329 cds_lfht_for_each_entry(uchan
->events
->ht
, &iter
.iter
, uevent
,
331 if (uevent
->enabled
== 0) {
332 ret
= ust_app_enable_event_glb(usess
, uchan
, uevent
);
340 /* Get all UST available events */
341 size
= ust_app_list_events(&events
);
343 ret
= LTTNG_ERR_UST_LIST_FAIL
;
347 for (i
= 0; i
< size
; i
++) {
349 * Check if event exist and if so, continue since it was enable
352 uevent
= trace_ust_find_event(uchan
->events
, events
[i
].name
, filter
,
354 if (uevent
!= NULL
) {
355 ret
= ust_app_enable_event_pid(usess
, uchan
, uevent
,
358 if (ret
!= -LTTNG_UST_ERR_EXIST
) {
359 ret
= LTTNG_ERR_UST_ENABLE_FAIL
;
366 /* Create ust event */
367 uevent
= trace_ust_create_event(&events
[i
], filter
);
368 if (uevent
== NULL
) {
369 ret
= LTTNG_ERR_FATAL
;
373 /* Create event for the specific PID */
374 ret
= ust_app_enable_event_pid(usess
, uchan
, uevent
,
377 if (ret
== -LTTNG_UST_ERR_EXIST
) {
378 ret
= LTTNG_ERR_UST_EVENT_EXIST
;
381 ret
= LTTNG_ERR_UST_ENABLE_FAIL
;
387 /* Add ltt ust event to channel */
389 add_unique_ust_event(uchan
->events
, uevent
);
398 trace_ust_destroy_event(uevent
);
407 * Enable UST tracepoint event for a channel from a UST session.
409 int event_ust_enable_tracepoint(struct ltt_ust_session
*usess
,
410 struct ltt_ust_channel
*uchan
, struct lttng_event
*event
,
411 struct lttng_filter_bytecode
*filter
)
413 int ret
= LTTNG_OK
, to_create
= 0;
414 struct ltt_ust_event
*uevent
;
422 uevent
= trace_ust_find_event(uchan
->events
, event
->name
, filter
,
424 if (uevent
== NULL
) {
425 uevent
= trace_ust_create_event(event
, filter
);
426 if (uevent
== NULL
) {
427 ret
= LTTNG_ERR_UST_ENABLE_FAIL
;
431 /* Valid to set it after the goto error since uevent is still NULL */
435 if (uevent
->enabled
) {
436 /* It's already enabled so everything is OK */
437 ret
= LTTNG_ERR_UST_EVENT_ENABLED
;
444 /* Create event on all UST registered apps for session */
445 ret
= ust_app_create_event_glb(usess
, uchan
, uevent
);
447 /* Enable event on all UST registered apps for session */
448 ret
= ust_app_enable_event_glb(usess
, uchan
, uevent
);
452 if (ret
== -LTTNG_UST_ERR_EXIST
) {
453 ret
= LTTNG_ERR_UST_EVENT_EXIST
;
456 ret
= LTTNG_ERR_UST_ENABLE_FAIL
;
462 /* Add ltt ust event to channel */
463 add_unique_ust_event(uchan
->events
, uevent
);
466 DBG("Event UST %s %s in channel %s", uevent
->attr
.name
,
467 to_create
? "created" : "enabled", uchan
->name
);
477 * Only destroy event on creation time (not enabling time) because if the
478 * event is found in the channel (to_create == 0), it means that at some
479 * point the enable_event worked and it's thus valid to keep it alive.
480 * Destroying it also implies that we also destroy it's shadow copy to sync
484 /* In this code path, the uevent was not added to the hash table */
485 trace_ust_destroy_event(uevent
);
492 * Disable UST tracepoint of a channel from a UST session.
494 int event_ust_disable_tracepoint(struct ltt_ust_session
*usess
,
495 struct ltt_ust_channel
*uchan
, char *event_name
)
498 struct ltt_ust_event
*uevent
;
499 struct lttng_ht_node_str
*node
;
500 struct lttng_ht_iter iter
;
512 * We use a custom lookup since we need the iterator for the next_duplicate
513 * call in the do while loop below.
515 cds_lfht_lookup(ht
->ht
, ht
->hash_fct((void *) event_name
, lttng_ht_seed
),
516 trace_ust_ht_match_event_by_name
, event_name
, &iter
.iter
);
517 node
= lttng_ht_iter_get_node_str(&iter
);
519 DBG2("Trace UST event NOT found by name %s", event_name
);
520 ret
= LTTNG_ERR_UST_EVENT_NOT_FOUND
;
525 uevent
= caa_container_of(node
, struct ltt_ust_event
, node
);
528 if (uevent
->enabled
== 0) {
529 /* It's already disabled so everything is OK */
533 ret
= ust_app_disable_event_glb(usess
, uchan
, uevent
);
534 if (ret
< 0 && ret
!= -LTTNG_UST_ERR_EXIST
) {
535 ret
= LTTNG_ERR_UST_DISABLE_FAIL
;
540 DBG2("Event UST %s disabled in channel %s", uevent
->attr
.name
,
544 /* Get next duplicate event by name. */
545 cds_lfht_next_duplicate(ht
->ht
, trace_ust_ht_match_event_by_name
,
546 event_name
, &iter
.iter
);
547 node
= lttng_ht_iter_get_node_str(&iter
);
558 * Disable all UST tracepoints for a channel from a UST session.
560 int event_ust_disable_all_tracepoints(struct ltt_ust_session
*usess
,
561 struct ltt_ust_channel
*uchan
)
564 struct lttng_ht_iter iter
;
565 struct ltt_ust_event
*uevent
= NULL
;
566 struct lttng_event
*events
= NULL
;
573 /* Disabling existing events */
574 cds_lfht_for_each_entry(uchan
->events
->ht
, &iter
.iter
, uevent
,
576 if (uevent
->enabled
== 1) {
577 ret
= event_ust_disable_tracepoint(usess
, uchan
,
585 /* Get all UST available events */
586 size
= ust_app_list_events(&events
);
588 ret
= LTTNG_ERR_UST_LIST_FAIL
;
592 for (i
= 0; i
< size
; i
++) {
593 ret
= event_ust_disable_tracepoint(usess
, uchan
,
595 if (ret
!= LTTNG_OK
) {
596 /* Continue to disable the rest... */