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 = -LTTNG_ERR_NOMEM;
  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,
 111                 const struct lttng_event_context *ctx)
 112 {
 113         int ret;
 114         struct ltt_ust_context *uctx = NULL;
 115
 116         assert(usess);
 117         assert(uchan);
 118         assert(ctx);
 119
 120         /* Check if context is duplicate */
 121         cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
 122                 if (trace_ust_match_context(uctx, ctx)) {
 123                         ret = LTTNG_ERR_UST_CONTEXT_EXIST;
 124                         goto duplicate;
 125                 }
 126         }
 127         uctx = NULL;
 128
 129         switch (domain) {
 130         case LTTNG_DOMAIN_JUL:
 131         case LTTNG_DOMAIN_LOG4J:
 132         {
 133                 struct agent *agt;
 134
 135                 if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
 136                         /* Other contexts are not needed by the agent. */
 137                         break;
 138                 }
 139                 agt = trace_ust_find_agent(usess, domain);
 140
 141                 if (!agt) {
 142                         agt = agent_create(domain);
 143                         if (!agt) {
 144                                 ret = -LTTNG_ERR_NOMEM;
 145                                 goto error;
 146                         }
 147                         agent_add(agt, usess->agents);
 148                 }
 149                 ret = agent_add_context(ctx, agt);
 150                 if (ret != LTTNG_OK) {
 151                         goto error;
 152                 }
 153
 154                 ret = agent_enable_context(ctx, domain);
 155                 if (ret != LTTNG_OK) {
 156                         goto error;
 157                 }
 158                 break;
 159         }
 160         case LTTNG_DOMAIN_UST:
 161                 break;
 162         default:
 163                 assert(0);
 164         }
 165
 166         /* Create ltt UST context */
 167         uctx = trace_ust_create_context(ctx);
 168         if (uctx == NULL) {
 169                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 170                 goto error;
 171         }
 172
 173         /* Add ltt UST context node to ltt UST channel */
 174         lttng_ht_add_ulong(uchan->ctx, &uctx->node);
 175         cds_list_add_tail(&uctx->list, &uchan->ctx_list);
 176
 177         if (!usess->active) {
 178                 goto end;
 179         }
 180
 181         ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
 182         if (ret < 0) {
 183                 goto error;
 184         }
 185 end:
 186         DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 187
 188         return 0;
 189
 190 error:
 191         free(uctx);
 192 duplicate:
 193         return ret;
 194 }
 195
 196 /*
 197  * Add kernel context to tracer.
 198  */
 199 int context_kernel_add(struct ltt_kernel_session *ksession,
 200                 const struct lttng_event_context *ctx, char *channel_name)
 201 {
 202         int ret;
 203         struct ltt_kernel_channel *kchan;
 204         struct ltt_kernel_context *kctx;
 205
 206         assert(ksession);
 207         assert(ctx);
 208         assert(channel_name);
 209
 210         kctx = trace_kernel_create_context(NULL);
 211         if (!kctx) {
 212                 ret = -LTTNG_ERR_NOMEM;
 213                 goto error;
 214         }
 215
 216         /* Setup kernel context structure */
 217         switch (ctx->ctx) {
 218         case LTTNG_EVENT_CONTEXT_PID:
 219                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
 220                 break;
 221         case LTTNG_EVENT_CONTEXT_PROCNAME:
 222                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
 223                 break;
 224         case LTTNG_EVENT_CONTEXT_PRIO:
 225                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
 226                 break;
 227         case LTTNG_EVENT_CONTEXT_NICE:
 228                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
 229                 break;
 230         case LTTNG_EVENT_CONTEXT_VPID:
 231                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
 232                 break;
 233         case LTTNG_EVENT_CONTEXT_TID:
 234                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
 235                 break;
 236         case LTTNG_EVENT_CONTEXT_VTID:
 237                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
 238                 break;
 239         case LTTNG_EVENT_CONTEXT_PPID:
 240                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
 241                 break;
 242         case LTTNG_EVENT_CONTEXT_VPPID:
 243                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
 244                 break;
 245         case LTTNG_EVENT_CONTEXT_HOSTNAME:
 246                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
 247                 break;
 248         case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
 249         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
 250                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
 251                 break;
 252         case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
 253                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
 254                 break;
 255         case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
 256                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
 257                 break;
 258         case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
 259                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
 260                 break;
 261         case LTTNG_EVENT_CONTEXT_MIGRATABLE:
 262                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
 263                 break;
 264         case LTTNG_EVENT_CONTEXT_CALLSTACK_KERNEL:
 265                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_CALLSTACK_KERNEL;
 266                 break;
 267         case LTTNG_EVENT_CONTEXT_CALLSTACK_USER:
 268                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_CALLSTACK_USER;
 269                 break;
 270         default:
 271                 ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
 272                 goto error;
 273         }
 274
 275         kctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
 276         kctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
 277         strncpy(kctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name,
 278                         LTTNG_SYMBOL_NAME_LEN);
 279         kctx->ctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 280
 281         if (*channel_name == '\0') {
 282                 ret = add_kctx_all_channels(ksession, kctx);
 283                 /* Ownership of kctx is transferred to the callee. */
 284                 kctx = NULL;
 285                 if (ret != LTTNG_OK) {
 286                         goto error;
 287                 }
 288         } else {
 289                 /* Get kernel channel */
 290                 kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
 291                 if (kchan == NULL) {
 292                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 293                         goto error;
 294                 }
 295
 296                 ret = add_kctx_to_channel(kctx, kchan);
 297                 /* Ownership of kctx is transferred to the callee. */
 298                 kctx = NULL;
 299                 if (ret != LTTNG_OK) {
 300                         goto error;
 301                 }
 302         }
 303
 304         ret = LTTNG_OK;
 305
 306 error:
 307         if (kctx) {
 308                 trace_kernel_destroy_context(kctx);
 309         }
 310         return ret;
 311 }
 312
 313 /*
 314  * Add UST context to tracer.
 315  */
 316 int context_ust_add(struct ltt_ust_session *usess,
 317                 enum lttng_domain_type domain,
 318                 const struct lttng_event_context *ctx,
 319                 char *channel_name)
 320 {
 321         int ret = LTTNG_OK;
 322         struct lttng_ht_iter iter;
 323         struct lttng_ht *chan_ht;
 324         struct ltt_ust_channel *uchan = NULL;
 325
 326         assert(usess);
 327         assert(ctx);
 328         assert(channel_name);
 329
 330         rcu_read_lock();
 331
 332         chan_ht = usess->domain_global.channels;
 333
 334         /* Get UST channel if defined */
 335         if (channel_name[0] != '\0') {
 336                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 337                 if (uchan == NULL) {
 338                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 339                         goto error;
 340                 }
 341         }
 342
 343         if (uchan) {
 344                 /* Add ctx to channel */
 345                 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 346         } else {
 347                 rcu_read_lock();
 348                 /* Add ctx all events, all channels */
 349                 cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
 350                         ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 351                         if (ret) {
 352                                 ERR("Failed to add context to channel %s",
 353                                                 uchan->name);
 354                                 continue;
 355                         }
 356                 }
 357                 rcu_read_unlock();
 358         }
 359
 360         switch (ret) {
 361         case LTTNG_ERR_UST_CONTEXT_EXIST:
 362                 break;
 363         case -ENOMEM:
 364         case -LTTNG_ERR_NOMEM:
 365                 ret = LTTNG_ERR_FATAL;
 366                 break;
 367         case -EINVAL:
 368                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 369                 break;
 370         case -ENOSYS:
 371                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 372                 break;
 373         default:
 374                 if (ret != 0 && ret != LTTNG_OK) {
 375                         ret = ret > 0 ? ret : LTTNG_ERR_UNK;
 376                 } else {
 377                         ret = LTTNG_OK;
 378                 }
 379                 break;
 380         }
 381
 382 error:
 383         rcu_read_unlock();
 384         return ret;
 385 }