Fix: uninitialized return value on error path
[lttng-tools.git] / src / bin / lttng-sessiond / context.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <unistd.h>
24 #include <urcu/list.h>
25
26 #include <common/error.h>
27 #include <common/sessiond-comm/sessiond-comm.h>
28
29 #include "context.h"
30 #include "kernel.h"
31 #include "ust-app.h"
32 #include "trace-ust.h"
33 #include "agent.h"
34
35 /*
36 * Add kernel context to all channel.
37 *
38 * Assumes the ownership of kctx.
39 */
40 static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
41 struct ltt_kernel_context *kctx)
42 {
43 int ret;
44 struct ltt_kernel_channel *kchan;
45
46 assert(ksession);
47 assert(kctx);
48
49 DBG("Adding kernel context to all channels");
50
51 /* Go over all channels */
52 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
53 struct ltt_kernel_context *kctx_copy;
54
55 kctx_copy = trace_kernel_copy_context(kctx);
56 if (!kctx_copy) {
57 PERROR("zmalloc ltt_kernel_context");
58 ret = -ENOMEM;
59 goto error;
60 }
61
62 /* Ownership of kctx_copy is transferred to the callee. */
63 ret = kernel_add_channel_context(kchan, kctx_copy);
64 kctx_copy = NULL;
65 if (ret != 0) {
66 goto error;
67 }
68 }
69
70 ret = LTTNG_OK;
71
72 error:
73 trace_kernel_destroy_context(kctx);
74 return ret;
75 }
76
77 /*
78 * Add kernel context to a specific channel.
79 *
80 * Assumes the ownership of kctx.
81 */
82 static int add_kctx_to_channel(struct ltt_kernel_context *kctx,
83 struct ltt_kernel_channel *kchan)
84 {
85 int ret;
86
87 assert(kchan);
88 assert(kctx);
89
90 DBG("Add kernel context to channel '%s'", kchan->channel->name);
91
92 /* Ownership of kctx is transferred to the callee. */
93 ret = kernel_add_channel_context(kchan, kctx);
94 kctx = NULL;
95 if (ret != 0) {
96 goto error;
97 }
98
99 ret = LTTNG_OK;
100
101 error:
102 return ret;
103 }
104
105 /*
106 * Add UST context to channel.
107 */
108 static int add_uctx_to_channel(struct ltt_ust_session *usess,
109 enum lttng_domain_type domain,
110 struct ltt_ust_channel *uchan, struct lttng_event_context *ctx)
111 {
112 int ret;
113 struct ltt_ust_context *uctx = NULL;
114
115 assert(usess);
116 assert(uchan);
117 assert(ctx);
118
119 /* Check if context is duplicate */
120 cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
121 if (trace_ust_match_context(uctx, ctx)) {
122 ret = -EEXIST;
123 goto duplicate;
124 }
125 }
126 uctx = NULL;
127
128 switch (domain) {
129 case LTTNG_DOMAIN_JUL:
130 case LTTNG_DOMAIN_LOG4J:
131 {
132 struct agent *agt;
133
134 if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
135 /* Other contexts are not needed by the agent. */
136 break;
137 }
138 agt = trace_ust_find_agent(usess, domain);
139
140 if (!agt) {
141 agt = agent_create(domain);
142 if (!agt) {
143 ret = LTTNG_ERR_NOMEM;
144 goto error;
145 }
146 agent_add(agt, usess->agents);
147 }
148 ret = agent_add_context(ctx, agt);
149 if (ret != LTTNG_OK) {
150 goto error;
151 }
152
153 ret = agent_enable_context(ctx, domain);
154 if (ret != LTTNG_OK) {
155 goto error;
156 }
157 break;
158 }
159 case LTTNG_DOMAIN_UST:
160 break;
161 default:
162 assert(0);
163 }
164
165 /* Create ltt UST context */
166 uctx = trace_ust_create_context(ctx);
167 if (uctx == NULL) {
168 ret = -EINVAL;
169 goto error;
170 }
171
172 ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
173 if (ret < 0) {
174 goto error;
175 }
176
177 rcu_read_lock();
178
179 /* Add ltt UST context node to ltt UST channel */
180 lttng_ht_add_ulong(uchan->ctx, &uctx->node);
181 rcu_read_unlock();
182 cds_list_add_tail(&uctx->list, &uchan->ctx_list);
183
184 DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
185
186 return 0;
187
188 error:
189 free(uctx);
190 duplicate:
191 return ret;
192 }
193
194 /*
195 * Add kernel context to tracer.
196 */
197 int context_kernel_add(struct ltt_kernel_session *ksession,
198 struct lttng_event_context *ctx, char *channel_name)
199 {
200 int ret;
201 struct ltt_kernel_channel *kchan;
202 struct ltt_kernel_context *kctx;
203
204 assert(ksession);
205 assert(ctx);
206 assert(channel_name);
207
208 kctx = trace_kernel_create_context(NULL);
209 if (!kctx) {
210 ret = LTTNG_ERR_NOMEM;
211 goto error;
212 }
213
214 /* Setup kernel context structure */
215 switch (ctx->ctx) {
216 case LTTNG_EVENT_CONTEXT_PID:
217 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
218 break;
219 case LTTNG_EVENT_CONTEXT_PROCNAME:
220 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
221 break;
222 case LTTNG_EVENT_CONTEXT_PRIO:
223 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
224 break;
225 case LTTNG_EVENT_CONTEXT_NICE:
226 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
227 break;
228 case LTTNG_EVENT_CONTEXT_VPID:
229 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
230 break;
231 case LTTNG_EVENT_CONTEXT_TID:
232 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
233 break;
234 case LTTNG_EVENT_CONTEXT_VTID:
235 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
236 break;
237 case LTTNG_EVENT_CONTEXT_PPID:
238 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
239 break;
240 case LTTNG_EVENT_CONTEXT_VPPID:
241 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
242 break;
243 case LTTNG_EVENT_CONTEXT_HOSTNAME:
244 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
245 break;
246 case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
247 case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
248 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
249 break;
250 case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
251 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
252 break;
253 case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
254 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
255 break;
256 case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
257 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
258 break;
259 case LTTNG_EVENT_CONTEXT_MIGRATABLE:
260 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
261 break;
262 default:
263 ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
264 goto error;
265 }
266
267 kctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
268 kctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
269 strncpy(kctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name,
270 LTTNG_SYMBOL_NAME_LEN);
271 kctx->ctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
272
273 if (*channel_name == '\0') {
274 ret = add_kctx_all_channels(ksession, kctx);
275 /* Ownership of kctx is transferred to the callee. */
276 kctx = NULL;
277 if (ret != LTTNG_OK) {
278 goto error;
279 }
280 } else {
281 /* Get kernel channel */
282 kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
283 if (kchan == NULL) {
284 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
285 goto error;
286 }
287
288 ret = add_kctx_to_channel(kctx, kchan);
289 /* Ownership of kctx is transferred to the callee. */
290 kctx = NULL;
291 if (ret != LTTNG_OK) {
292 goto error;
293 }
294 }
295
296 ret = LTTNG_OK;
297
298 error:
299 if (kctx) {
300 trace_kernel_destroy_context(kctx);
301 }
302 return ret;
303 }
304
305 /*
306 * Add UST context to tracer.
307 */
308 int context_ust_add(struct ltt_ust_session *usess,
309 enum lttng_domain_type domain, struct lttng_event_context *ctx,
310 char *channel_name)
311 {
312 int ret = LTTNG_OK;
313 struct lttng_ht_iter iter;
314 struct lttng_ht *chan_ht;
315 struct ltt_ust_channel *uchan = NULL;
316
317 assert(usess);
318 assert(ctx);
319 assert(channel_name);
320
321 rcu_read_lock();
322
323 chan_ht = usess->domain_global.channels;
324
325 /* Get UST channel if defined */
326 if (channel_name[0] != '\0') {
327 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
328 if (uchan == NULL) {
329 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
330 goto error;
331 }
332 }
333
334 if (uchan) {
335 /* Add ctx to channel */
336 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
337 } else {
338 rcu_read_lock();
339 /* Add ctx all events, all channels */
340 cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
341 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
342 if (ret < 0) {
343 ERR("Failed to add context to channel %s",
344 uchan->name);
345 continue;
346 }
347 }
348 rcu_read_unlock();
349 }
350
351 switch (ret) {
352 case -EEXIST:
353 ret = LTTNG_ERR_UST_CONTEXT_EXIST;
354 break;
355 case -ENOMEM:
356 ret = LTTNG_ERR_FATAL;
357 break;
358 case -EINVAL:
359 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
360 break;
361 case -ENOSYS:
362 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
363 break;
364 default:
365 ret = LTTNG_OK;
366 break;
367 }
368
369 error:
370 rcu_read_unlock();
371 return ret;
372 }
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