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                         goto error;
  59                 }
  60
  61                 /* Ownership of kctx_copy is transferred to the callee. */
  62                 ret = kernel_add_channel_context(kchan, kctx_copy);
  63                 kctx_copy = NULL;
  64                 if (ret != 0) {
  65                         goto error;
  66                 }
  67         }
  68
  69         ret = LTTNG_OK;
  70
  71 error:
  72         trace_kernel_destroy_context(kctx);
  73         return ret;
  74 }
  75
  76 /*
  77  * Add kernel context to a specific channel.
  78  *
  79  * Assumes the ownership of kctx.
  80  */
  81 static int add_kctx_to_channel(struct ltt_kernel_context *kctx,
  82                 struct ltt_kernel_channel *kchan)
  83 {
  84         int ret;
  85
  86         assert(kchan);
  87         assert(kctx);
  88
  89         DBG("Add kernel context to channel '%s'", kchan->channel->name);
  90
  91         /* Ownership of kctx is transferred to the callee. */
  92         ret = kernel_add_channel_context(kchan, kctx);
  93         kctx = NULL;
  94         if (ret != 0) {
  95                 goto error;
  96         }
  97
  98         ret = LTTNG_OK;
  99
 100 error:
 101         return ret;
 102 }
 103
 104 /*
 105  * Add UST context to channel.
 106  */
 107 static int add_uctx_to_channel(struct ltt_ust_session *usess,
 108                 enum lttng_domain_type domain,
 109                 struct ltt_ust_channel *uchan, struct lttng_event_context *ctx)
 110 {
 111         int ret;
 112         struct ltt_ust_context *uctx = NULL;
 113
 114         assert(usess);
 115         assert(uchan);
 116         assert(ctx);
 117
 118         /* Check if context is duplicate */
 119         cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
 120                 if (trace_ust_match_context(uctx, ctx)) {
 121                         ret = -EEXIST;
 122                         goto duplicate;
 123                 }
 124         }
 125         uctx = NULL;
 126
 127         switch (domain) {
 128         case LTTNG_DOMAIN_JUL:
 129         case LTTNG_DOMAIN_LOG4J:
 130         {
 131                 struct agent *agt;
 132
 133                 if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
 134                         /* Other contexts are not needed by the agent. */
 135                         break;
 136                 }
 137                 agt = trace_ust_find_agent(usess, domain);
 138
 139                 if (!agt) {
 140                         agt = agent_create(domain);
 141                         if (!agt) {
 142                                 ret = LTTNG_ERR_NOMEM;
 143                                 goto error;
 144                         }
 145                         agent_add(agt, usess->agents);
 146                 }
 147                 ret = agent_add_context(ctx, agt);
 148                 if (ret != LTTNG_OK) {
 149                         goto error;
 150                 }
 151
 152                 ret = agent_enable_context(ctx, domain);
 153                 if (ret != LTTNG_OK) {
 154                         goto error;
 155                 }
 156                 break;
 157         }
 158         case LTTNG_DOMAIN_UST:
 159                 break;
 160         default:
 161                 assert(0);
 162         }
 163
 164         /* Create ltt UST context */
 165         uctx = trace_ust_create_context(ctx);
 166         if (uctx == NULL) {
 167                 ret = -EINVAL;
 168                 goto error;
 169         }
 170
 171         ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
 172         if (ret < 0) {
 173                 goto error;
 174         }
 175
 176         rcu_read_lock();
 177
 178         /* Add ltt UST context node to ltt UST channel */
 179         lttng_ht_add_ulong(uchan->ctx, &uctx->node);
 180         rcu_read_unlock();
 181         cds_list_add_tail(&uctx->list, &uchan->ctx_list);
 182
 183         DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 184
 185         return 0;
 186
 187 error:
 188         free(uctx);
 189 duplicate:
 190         return ret;
 191 }
 192
 193 /*
 194  * Add kernel context to tracer.
 195  */
 196 int context_kernel_add(struct ltt_kernel_session *ksession,
 197                 struct lttng_event_context *ctx, char *channel_name)
 198 {
 199         int ret;
 200         struct ltt_kernel_channel *kchan;
 201         struct ltt_kernel_context *kctx;
 202
 203         assert(ksession);
 204         assert(ctx);
 205         assert(channel_name);
 206
 207         kctx = trace_kernel_create_context(NULL);
 208         if (!kctx) {
 209                 ret = LTTNG_ERR_NOMEM;
 210                 goto error;
 211         }
 212
 213         /* Setup kernel context structure */
 214         switch (ctx->ctx) {
 215         case LTTNG_EVENT_CONTEXT_PID:
 216                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
 217                 break;
 218         case LTTNG_EVENT_CONTEXT_PROCNAME:
 219                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
 220                 break;
 221         case LTTNG_EVENT_CONTEXT_PRIO:
 222                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
 223                 break;
 224         case LTTNG_EVENT_CONTEXT_NICE:
 225                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
 226                 break;
 227         case LTTNG_EVENT_CONTEXT_VPID:
 228                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
 229                 break;
 230         case LTTNG_EVENT_CONTEXT_TID:
 231                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
 232                 break;
 233         case LTTNG_EVENT_CONTEXT_VTID:
 234                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
 235                 break;
 236         case LTTNG_EVENT_CONTEXT_PPID:
 237                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
 238                 break;
 239         case LTTNG_EVENT_CONTEXT_VPPID:
 240                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
 241                 break;
 242         case LTTNG_EVENT_CONTEXT_HOSTNAME:
 243                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
 244                 break;
 245         case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
 246         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
 247                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
 248                 break;
 249         case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
 250                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
 251                 break;
 252         case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
 253                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
 254                 break;
 255         case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
 256                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
 257                 break;
 258         case LTTNG_EVENT_CONTEXT_MIGRATABLE:
 259                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
 260                 break;
 261         default:
 262                 ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
 263                 goto error;
 264         }
 265
 266         kctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
 267         kctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
 268         strncpy(kctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name,
 269                         LTTNG_SYMBOL_NAME_LEN);
 270         kctx->ctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 271
 272         if (*channel_name == '\0') {
 273                 ret = add_kctx_all_channels(ksession, kctx);
 274                 /* Ownership of kctx is transferred to the callee. */
 275                 kctx = NULL;
 276                 if (ret != LTTNG_OK) {
 277                         goto error;
 278                 }
 279         } else {
 280                 /* Get kernel channel */
 281                 kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
 282                 if (kchan == NULL) {
 283                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 284                         goto error;
 285                 }
 286
 287                 ret = add_kctx_to_channel(kctx, kchan);
 288                 /* Ownership of kctx is transferred to the callee. */
 289                 kctx = NULL;
 290                 if (ret != LTTNG_OK) {
 291                         goto error;
 292                 }
 293         }
 294
 295         ret = LTTNG_OK;
 296
 297 error:
 298         if (kctx) {
 299                 trace_kernel_destroy_context(kctx);
 300         }
 301         return ret;
 302 }
 303
 304 /*
 305  * Add UST context to tracer.
 306  */
 307 int context_ust_add(struct ltt_ust_session *usess,
 308                 enum lttng_domain_type domain, struct lttng_event_context *ctx,
 309                 char *channel_name)
 310 {
 311         int ret = LTTNG_OK;
 312         struct lttng_ht_iter iter;
 313         struct lttng_ht *chan_ht;
 314         struct ltt_ust_channel *uchan = NULL;
 315
 316         assert(usess);
 317         assert(ctx);
 318         assert(channel_name);
 319
 320         rcu_read_lock();
 321
 322         chan_ht = usess->domain_global.channels;
 323
 324         /* Get UST channel if defined */
 325         if (channel_name[0] != '\0') {
 326                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 327                 if (uchan == NULL) {
 328                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 329                         goto error;
 330                 }
 331         }
 332
 333         if (uchan) {
 334                 /* Add ctx to channel */
 335                 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 336         } else {
 337                 rcu_read_lock();
 338                 /* Add ctx all events, all channels */
 339                 cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
 340                         ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 341                         if (ret < 0) {
 342                                 ERR("Failed to add context to channel %s",
 343                                                 uchan->name);
 344                                 continue;
 345                         }
 346                 }
 347                 rcu_read_unlock();
 348         }
 349
 350         switch (ret) {
 351         case -EEXIST:
 352                 ret = LTTNG_ERR_UST_CONTEXT_EXIST;
 353                 break;
 354         case -ENOMEM:
 355                 ret = LTTNG_ERR_FATAL;
 356                 break;
 357         case -EINVAL:
 358                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 359                 break;
 360         case -ENOSYS:
 361                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 362                 break;
 363         default:
 364                 ret = LTTNG_OK;
 365                 break;
 366         }
 367
 368 error:
 369         rcu_read_unlock();
 370         return ret;
 371 }