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, 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 = LTTNG_ERR_UST_CONTEXT_EXIST;
 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 = LTTNG_ERR_UST_CONTEXT_INVAL;
 169                 goto error;
 170         }
 171
 172         /* Add ltt UST context node to ltt UST channel */
 173         lttng_ht_add_ulong(uchan->ctx, &uctx->node);
 174         cds_list_add_tail(&uctx->list, &uchan->ctx_list);
 175
 176         if (!usess->active) {
 177                 goto end;
 178         }
 179
 180         ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
 181         if (ret < 0) {
 182                 goto error;
 183         }
 184 end:
 185         DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 186
 187         return 0;
 188
 189 error:
 190         free(uctx);
 191 duplicate:
 192         return ret;
 193 }
 194
 195 /*
 196  * Add kernel context to tracer.
 197  */
 198 int context_kernel_add(struct ltt_kernel_session *ksession,
 199                 struct lttng_event_context *ctx, char *channel_name)
 200 {
 201         int ret;
 202         struct ltt_kernel_channel *kchan;
 203         struct ltt_kernel_context *kctx;
 204
 205         assert(ksession);
 206         assert(ctx);
 207         assert(channel_name);
 208
 209         kctx = trace_kernel_create_context(NULL);
 210         if (!kctx) {
 211                 ret = -LTTNG_ERR_NOMEM;
 212                 goto error;
 213         }
 214
 215         /* Setup kernel context structure */
 216         switch (ctx->ctx) {
 217         case LTTNG_EVENT_CONTEXT_PID:
 218                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
 219                 break;
 220         case LTTNG_EVENT_CONTEXT_PROCNAME:
 221                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
 222                 break;
 223         case LTTNG_EVENT_CONTEXT_PRIO:
 224                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
 225                 break;
 226         case LTTNG_EVENT_CONTEXT_NICE:
 227                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
 228                 break;
 229         case LTTNG_EVENT_CONTEXT_VPID:
 230                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
 231                 break;
 232         case LTTNG_EVENT_CONTEXT_TID:
 233                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
 234                 break;
 235         case LTTNG_EVENT_CONTEXT_VTID:
 236                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
 237                 break;
 238         case LTTNG_EVENT_CONTEXT_PPID:
 239                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
 240                 break;
 241         case LTTNG_EVENT_CONTEXT_VPPID:
 242                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
 243                 break;
 244         case LTTNG_EVENT_CONTEXT_HOSTNAME:
 245                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
 246                 break;
 247         case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
 248         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
 249                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
 250                 break;
 251         case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
 252                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
 253                 break;
 254         case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
 255                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
 256                 break;
 257         case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
 258                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
 259                 break;
 260         case LTTNG_EVENT_CONTEXT_MIGRATABLE:
 261                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
 262                 break;
 263         case LTTNG_EVENT_CONTEXT_CALLSTACK_KERNEL:
 264                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_CALLSTACK_KERNEL;
 265                 break;
 266         case LTTNG_EVENT_CONTEXT_CALLSTACK_USER:
 267                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_CALLSTACK_USER;
 268                 break;
 269         default:
 270                 ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
 271                 goto error;
 272         }
 273
 274         kctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
 275         kctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
 276         strncpy(kctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name,
 277                         LTTNG_SYMBOL_NAME_LEN);
 278         kctx->ctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 279
 280         if (*channel_name == '\0') {
 281                 ret = add_kctx_all_channels(ksession, kctx);
 282                 /* Ownership of kctx is transferred to the callee. */
 283                 kctx = NULL;
 284                 if (ret != LTTNG_OK) {
 285                         goto error;
 286                 }
 287         } else {
 288                 /* Get kernel channel */
 289                 kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
 290                 if (kchan == NULL) {
 291                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 292                         goto error;
 293                 }
 294
 295                 ret = add_kctx_to_channel(kctx, kchan);
 296                 /* Ownership of kctx is transferred to the callee. */
 297                 kctx = NULL;
 298                 if (ret != LTTNG_OK) {
 299                         goto error;
 300                 }
 301         }
 302
 303         ret = LTTNG_OK;
 304
 305 error:
 306         if (kctx) {
 307                 trace_kernel_destroy_context(kctx);
 308         }
 309         return ret;
 310 }
 311
 312 /*
 313  * Add UST context to tracer.
 314  */
 315 int context_ust_add(struct ltt_ust_session *usess,
 316                 enum lttng_domain_type domain, struct lttng_event_context *ctx,
 317                 char *channel_name)
 318 {
 319         int ret = LTTNG_OK;
 320         struct lttng_ht_iter iter;
 321         struct lttng_ht *chan_ht;
 322         struct ltt_ust_channel *uchan = NULL;
 323
 324         assert(usess);
 325         assert(ctx);
 326         assert(channel_name);
 327
 328         rcu_read_lock();
 329
 330         chan_ht = usess->domain_global.channels;
 331
 332         /* Get UST channel if defined */
 333         if (channel_name[0] != '\0') {
 334                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 335                 if (uchan == NULL) {
 336                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 337                         goto error;
 338                 }
 339         }
 340
 341         if (uchan) {
 342                 /* Add ctx to channel */
 343                 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 344         } else {
 345                 rcu_read_lock();
 346                 /* Add ctx all events, all channels */
 347                 cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
 348                         ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 349                         if (ret) {
 350                                 ERR("Failed to add context to channel %s",
 351                                                 uchan->name);
 352                                 continue;
 353                         }
 354                 }
 355                 rcu_read_unlock();
 356         }
 357
 358         switch (ret) {
 359         case LTTNG_ERR_UST_CONTEXT_EXIST:
 360                 break;
 361         case -ENOMEM:
 362         case -LTTNG_ERR_NOMEM:
 363                 ret = LTTNG_ERR_FATAL;
 364                 break;
 365         case -EINVAL:
 366                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 367                 break;
 368         case -ENOSYS:
 369                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 370                 break;
 371         default:
 372                 if (ret != 0 && ret != LTTNG_OK) {
 373                         ret = ret > 0 ? ret : LTTNG_ERR_UNK;
 374                 } else {
 375                         ret = LTTNG_OK;
 376                 }
 377                 break;
 378         }
 379
 380 error:
 381         rcu_read_unlock();
 382         return ret;
 383 }