src/bin/lttng-sessiond/context.cpp

   1 /*
   2  * Copyright (C) 2011 EfficiOS Inc.
   3  * Copyright (C) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4  *
   5  * SPDX-License-Identifier: GPL-2.0-only
   6  *
   7  */
   8
   9 #define _LGPL_SOURCE
  10 #include "agent.hpp"
  11 #include "context.hpp"
  12 #include "kernel.hpp"
  13 #include "trace-ust.hpp"
  14 #include "ust-app.hpp"
  15
  16 #include <common/error.hpp>
  17 #include <common/sessiond-comm/sessiond-comm.hpp>
  18
  19 #include <stdio.h>
  20 #include <unistd.h>
  21 #include <urcu/list.h>
  22
  23 /*
  24  * Add kernel context to all channel.
  25  *
  26  * Assumes the ownership of kctx.
  27  */
  28 static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
  29                                  struct ltt_kernel_context *kctx)
  30 {
  31         int ret;
  32         struct ltt_kernel_channel *kchan;
  33
  34         LTTNG_ASSERT(ksession);
  35         LTTNG_ASSERT(kctx);
  36
  37         DBG("Adding kernel context to all channels");
  38
  39         /* Go over all channels */
  40         cds_list_for_each_entry (kchan, &ksession->channel_list.head, list) {
  41                 struct ltt_kernel_context *kctx_copy;
  42
  43                 kctx_copy = trace_kernel_copy_context(kctx);
  44                 if (!kctx_copy) {
  45                         PERROR("zmalloc ltt_kernel_context");
  46                         ret = -LTTNG_ERR_NOMEM;
  47                         goto error;
  48                 }
  49
  50                 /* Ownership of kctx_copy is transferred to the callee. */
  51                 ret = kernel_add_channel_context(kchan, kctx_copy);
  52                 kctx_copy = nullptr;
  53                 if (ret != 0) {
  54                         goto error;
  55                 }
  56         }
  57
  58         ret = LTTNG_OK;
  59
  60 error:
  61         trace_kernel_destroy_context(kctx);
  62         return ret;
  63 }
  64
  65 /*
  66  * Add kernel context to a specific channel.
  67  *
  68  * Assumes the ownership of kctx.
  69  */
  70 static int add_kctx_to_channel(struct ltt_kernel_context *kctx, struct ltt_kernel_channel *kchan)
  71 {
  72         int ret;
  73
  74         LTTNG_ASSERT(kchan);
  75         LTTNG_ASSERT(kctx);
  76
  77         DBG("Add kernel context to channel '%s'", kchan->channel->name);
  78
  79         /* Ownership of kctx is transferred to the callee. */
  80         ret = kernel_add_channel_context(kchan, kctx);
  81         kctx = nullptr;
  82         if (ret != 0) {
  83                 goto error;
  84         }
  85
  86         ret = LTTNG_OK;
  87
  88 error:
  89         return ret;
  90 }
  91
  92 /*
  93  * Add UST context to channel.
  94  */
  95 static int add_uctx_to_channel(struct ltt_ust_session *usess,
  96                                enum lttng_domain_type domain,
  97                                struct ltt_ust_channel *uchan,
  98                                const struct lttng_event_context *ctx)
  99 {
 100         int ret;
 101         struct ltt_ust_context *uctx = nullptr;
 102
 103         LTTNG_ASSERT(usess);
 104         LTTNG_ASSERT(uchan);
 105         LTTNG_ASSERT(ctx);
 106
 107         /* Check if context is duplicate */
 108         cds_list_for_each_entry (uctx, &uchan->ctx_list, list) {
 109                 if (trace_ust_match_context(uctx, ctx)) {
 110                         ret = LTTNG_ERR_UST_CONTEXT_EXIST;
 111                         goto duplicate;
 112                 }
 113         }
 114         uctx = nullptr;
 115
 116         switch (domain) {
 117         case LTTNG_DOMAIN_JUL:
 118         case LTTNG_DOMAIN_LOG4J:
 119         {
 120                 struct agent *agt;
 121
 122                 if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
 123                         /* Other contexts are not needed by the agent. */
 124                         break;
 125                 }
 126                 agt = trace_ust_find_agent(usess, domain);
 127
 128                 if (!agt) {
 129                         agt = agent_create(domain);
 130                         if (!agt) {
 131                                 ret = -LTTNG_ERR_NOMEM;
 132                                 goto error;
 133                         }
 134                         agent_add(agt, usess->agents);
 135                 }
 136                 ret = agent_add_context(ctx, agt);
 137                 if (ret != LTTNG_OK) {
 138                         goto error;
 139                 }
 140
 141                 ret = agent_enable_context(ctx, domain);
 142                 if (ret != LTTNG_OK) {
 143                         goto error;
 144                 }
 145                 break;
 146         }
 147         case LTTNG_DOMAIN_UST:
 148                 break;
 149         default:
 150                 abort();
 151         }
 152
 153         /* Create ltt UST context */
 154         uctx = trace_ust_create_context(ctx);
 155         if (uctx == nullptr) {
 156                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 157                 goto error;
 158         }
 159
 160         /* Add ltt UST context node to ltt UST channel */
 161         lttng_ht_add_ulong(uchan->ctx, &uctx->node);
 162         cds_list_add_tail(&uctx->list, &uchan->ctx_list);
 163
 164         if (!usess->active) {
 165                 goto end;
 166         }
 167
 168         ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
 169         if (ret < 0) {
 170                 goto error;
 171         }
 172 end:
 173         DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 174
 175         return 0;
 176
 177 error:
 178         free(uctx);
 179 duplicate:
 180         return ret;
 181 }
 182
 183 /*
 184  * Add kernel context to tracer.
 185  */
 186 int context_kernel_add(struct ltt_kernel_session *ksession,
 187                        const struct lttng_event_context *ctx,
 188                        const char *channel_name)
 189 {
 190         int ret;
 191         struct ltt_kernel_channel *kchan;
 192         struct ltt_kernel_context *kctx;
 193
 194         LTTNG_ASSERT(ksession);
 195         LTTNG_ASSERT(ctx);
 196         LTTNG_ASSERT(channel_name);
 197
 198         kctx = trace_kernel_create_context(nullptr);
 199         if (!kctx) {
 200                 ret = -LTTNG_ERR_NOMEM;
 201                 goto error;
 202         }
 203
 204         /* Setup kernel context structure */
 205         switch (ctx->ctx) {
 206         case LTTNG_EVENT_CONTEXT_PID:
 207                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_PID;
 208                 break;
 209         case LTTNG_EVENT_CONTEXT_PROCNAME:
 210                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_PROCNAME;
 211                 break;
 212         case LTTNG_EVENT_CONTEXT_PRIO:
 213                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_PRIO;
 214                 break;
 215         case LTTNG_EVENT_CONTEXT_NICE:
 216                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_NICE;
 217                 break;
 218         case LTTNG_EVENT_CONTEXT_VPID:
 219                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VPID;
 220                 break;
 221         case LTTNG_EVENT_CONTEXT_TID:
 222                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_TID;
 223                 break;
 224         case LTTNG_EVENT_CONTEXT_VTID:
 225                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VTID;
 226                 break;
 227         case LTTNG_EVENT_CONTEXT_PPID:
 228                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_PPID;
 229                 break;
 230         case LTTNG_EVENT_CONTEXT_VPPID:
 231                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VPPID;
 232                 break;
 233         case LTTNG_EVENT_CONTEXT_HOSTNAME:
 234                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_HOSTNAME;
 235                 break;
 236         case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
 237         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
 238                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_PERF_CPU_COUNTER;
 239                 break;
 240         case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
 241                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_INTERRUPTIBLE;
 242                 break;
 243         case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
 244                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_PREEMPTIBLE;
 245                 break;
 246         case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
 247                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_NEED_RESCHEDULE;
 248                 break;
 249         case LTTNG_EVENT_CONTEXT_MIGRATABLE:
 250                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_MIGRATABLE;
 251                 break;
 252         case LTTNG_EVENT_CONTEXT_CALLSTACK_KERNEL:
 253                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_CALLSTACK_KERNEL;
 254                 break;
 255         case LTTNG_EVENT_CONTEXT_CALLSTACK_USER:
 256                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_CALLSTACK_USER;
 257                 break;
 258         case LTTNG_EVENT_CONTEXT_CGROUP_NS:
 259                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_CGROUP_NS;
 260                 break;
 261         case LTTNG_EVENT_CONTEXT_IPC_NS:
 262                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_IPC_NS;
 263                 break;
 264         case LTTNG_EVENT_CONTEXT_MNT_NS:
 265                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_MNT_NS;
 266                 break;
 267         case LTTNG_EVENT_CONTEXT_NET_NS:
 268                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_NET_NS;
 269                 break;
 270         case LTTNG_EVENT_CONTEXT_PID_NS:
 271                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_PID_NS;
 272                 break;
 273         case LTTNG_EVENT_CONTEXT_TIME_NS:
 274                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_TIME_NS;
 275                 break;
 276         case LTTNG_EVENT_CONTEXT_USER_NS:
 277                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_USER_NS;
 278                 break;
 279         case LTTNG_EVENT_CONTEXT_UTS_NS:
 280                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_UTS_NS;
 281                 break;
 282         case LTTNG_EVENT_CONTEXT_UID:
 283                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_UID;
 284                 break;
 285         case LTTNG_EVENT_CONTEXT_EUID:
 286                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_EUID;
 287                 break;
 288         case LTTNG_EVENT_CONTEXT_SUID:
 289                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_SUID;
 290                 break;
 291         case LTTNG_EVENT_CONTEXT_GID:
 292                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_GID;
 293                 break;
 294         case LTTNG_EVENT_CONTEXT_EGID:
 295                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_EGID;
 296                 break;
 297         case LTTNG_EVENT_CONTEXT_SGID:
 298                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_SGID;
 299                 break;
 300         case LTTNG_EVENT_CONTEXT_VUID:
 301                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VUID;
 302                 break;
 303         case LTTNG_EVENT_CONTEXT_VEUID:
 304                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VEUID;
 305                 break;
 306         case LTTNG_EVENT_CONTEXT_VSUID:
 307                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VSUID;
 308                 break;
 309         case LTTNG_EVENT_CONTEXT_VGID:
 310                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VGID;
 311                 break;
 312         case LTTNG_EVENT_CONTEXT_VEGID:
 313                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VEGID;
 314                 break;
 315         case LTTNG_EVENT_CONTEXT_VSGID:
 316                 kctx->ctx.ctx = LTTNG_KERNEL_ABI_CONTEXT_VSGID;
 317                 break;
 318         default:
 319                 ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
 320                 goto error;
 321         }
 322
 323         kctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
 324         kctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
 325         strncpy(kctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name, LTTNG_SYMBOL_NAME_LEN);
 326         kctx->ctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 327
 328         if (*channel_name == '\0') {
 329                 ret = add_kctx_all_channels(ksession, kctx);
 330                 /* Ownership of kctx is transferred to the callee. */
 331                 kctx = nullptr;
 332                 if (ret != LTTNG_OK) {
 333                         goto error;
 334                 }
 335         } else {
 336                 /* Get kernel channel */
 337                 kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
 338                 if (kchan == nullptr) {
 339                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 340                         goto error;
 341                 }
 342
 343                 ret = add_kctx_to_channel(kctx, kchan);
 344                 /* Ownership of kctx is transferred to the callee. */
 345                 kctx = nullptr;
 346                 if (ret != LTTNG_OK) {
 347                         goto error;
 348                 }
 349         }
 350
 351         ret = LTTNG_OK;
 352
 353 error:
 354         if (kctx) {
 355                 trace_kernel_destroy_context(kctx);
 356         }
 357         return ret;
 358 }
 359
 360 /*
 361  * Add UST context to tracer.
 362  */
 363 int context_ust_add(struct ltt_ust_session *usess,
 364                     enum lttng_domain_type domain,
 365                     const struct lttng_event_context *ctx,
 366                     const char *channel_name)
 367 {
 368         int ret = LTTNG_OK;
 369         struct lttng_ht_iter iter;
 370         struct lttng_ht *chan_ht;
 371         struct ltt_ust_channel *uchan = nullptr;
 372
 373         LTTNG_ASSERT(usess);
 374         LTTNG_ASSERT(ctx);
 375         LTTNG_ASSERT(channel_name);
 376
 377         rcu_read_lock();
 378
 379         chan_ht = usess->domain_global.channels;
 380
 381         /* Get UST channel if defined */
 382         if (channel_name[0] != '\0') {
 383                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 384                 if (uchan == nullptr) {
 385                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 386                         goto error;
 387                 }
 388         }
 389
 390         if (uchan) {
 391                 /* Add ctx to channel */
 392                 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 393         } else {
 394                 rcu_read_lock();
 395                 /* Add ctx all events, all channels */
 396                 cds_lfht_for_each_entry (chan_ht->ht, &iter.iter, uchan, node.node) {
 397                         ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 398                         if (ret) {
 399                                 ERR("Failed to add context to channel %s", uchan->name);
 400                                 continue;
 401                         }
 402                 }
 403                 rcu_read_unlock();
 404         }
 405
 406         switch (ret) {
 407         case LTTNG_ERR_UST_CONTEXT_EXIST:
 408                 break;
 409         case -ENOMEM:
 410         case -LTTNG_ERR_NOMEM:
 411                 ret = LTTNG_ERR_FATAL;
 412                 break;
 413         case -EINVAL:
 414                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 415                 break;
 416         case -ENOSYS:
 417                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 418                 break;
 419         default:
 420                 if (ret != 0 && ret != LTTNG_OK) {
 421                         ret = ret > 0 ? ret : LTTNG_ERR_UNK;
 422                 } else {
 423                         ret = LTTNG_OK;
 424                 }
 425                 break;
 426         }
 427
 428 error:
 429         rcu_read_unlock();
 430         return ret;
 431 }