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 static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
  39                 struct ltt_kernel_context *kctx)
  40 {
  41         int ret;
  42         struct ltt_kernel_channel *kchan;
  43
  44         assert(ksession);
  45         assert(kctx);
  46
  47         DBG("Adding kernel context to all channels");
  48
  49         /* Go over all channels */
  50         cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
  51                 ret = kernel_add_channel_context(kchan, kctx);
  52                 if (ret != 0) {
  53                         goto error;
  54                 }
  55         }
  56
  57         ret = LTTNG_OK;
  58
  59 error:
  60         return ret;
  61 }
  62
  63 /*
  64  * Add kernel context to a specific channel.
  65  */
  66 static int add_kctx_to_channel(struct ltt_kernel_context *kctx,
  67                 struct ltt_kernel_channel *kchan)
  68 {
  69         int ret;
  70
  71         assert(kchan);
  72         assert(kctx);
  73
  74         DBG("Add kernel context to channel '%s'", kchan->channel->name);
  75
  76         ret = kernel_add_channel_context(kchan, kctx);
  77         if (ret != 0) {
  78                 goto error;
  79         }
  80
  81         ret = LTTNG_OK;
  82
  83 error:
  84         return ret;
  85 }
  86
  87 /*
  88  * Add UST context to channel.
  89  */
  90 static int add_uctx_to_channel(struct ltt_ust_session *usess,
  91                 enum lttng_domain_type domain,
  92                 struct ltt_ust_channel *uchan, struct lttng_event_context *ctx)
  93 {
  94         int ret;
  95         struct ltt_ust_context *uctx = NULL;
  96
  97         assert(usess);
  98         assert(uchan);
  99         assert(ctx);
 100
 101         /* Check if context is duplicate */
 102         cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
 103                 if (trace_ust_match_context(uctx, ctx)) {
 104                         ret = -EEXIST;
 105                         goto duplicate;
 106                 }
 107         }
 108         uctx = NULL;
 109
 110         switch (domain) {
 111         case LTTNG_DOMAIN_JUL:
 112         case LTTNG_DOMAIN_LOG4J:
 113         {
 114                 struct agent *agt;
 115
 116                 if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
 117                         /* Other contexts are not needed by the agent. */
 118                         break;
 119                 }
 120                 agt = trace_ust_find_agent(usess, domain);
 121
 122                 if (!agt) {
 123                         agt = agent_create(domain);
 124                         if (!agt) {
 125                                 ret = LTTNG_ERR_NOMEM;
 126                                 goto error;
 127                         }
 128                         agent_add(agt, usess->agents);
 129                 }
 130                 ret = agent_add_context(ctx, agt);
 131                 if (ret != LTTNG_OK) {
 132                         goto error;
 133                 }
 134
 135                 ret = agent_enable_context(ctx, domain);
 136                 if (ret != LTTNG_OK) {
 137                         goto error;
 138                 }
 139                 break;
 140         }
 141         case LTTNG_DOMAIN_UST:
 142                 break;
 143         default:
 144                 assert(0);
 145         }
 146
 147         /* Create ltt UST context */
 148         uctx = trace_ust_create_context(ctx);
 149         if (uctx == NULL) {
 150                 ret = -EINVAL;
 151                 goto error;
 152         }
 153
 154         ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
 155         if (ret < 0) {
 156                 goto error;
 157         }
 158
 159         rcu_read_lock();
 160
 161         /* Add ltt UST context node to ltt UST channel */
 162         lttng_ht_add_ulong(uchan->ctx, &uctx->node);
 163         rcu_read_unlock();
 164         cds_list_add_tail(&uctx->list, &uchan->ctx_list);
 165
 166         DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 167
 168         return 0;
 169
 170 error:
 171         free(uctx);
 172 duplicate:
 173         return ret;
 174 }
 175
 176 /*
 177  * Add kernel context to tracer.
 178  */
 179 int context_kernel_add(struct ltt_kernel_session *ksession,
 180                 struct lttng_event_context *ctx, char *channel_name)
 181 {
 182         int ret;
 183         struct ltt_kernel_channel *kchan;
 184         struct ltt_kernel_context *kctx;
 185
 186         assert(ksession);
 187         assert(ctx);
 188         assert(channel_name);
 189
 190         kctx = trace_kernel_create_context(NULL);
 191         if (!kctx) {
 192                 ret = LTTNG_ERR_NOMEM;
 193                 goto error;
 194         }
 195
 196         /* Setup kernel context structure */
 197         switch (ctx->ctx) {
 198         case LTTNG_EVENT_CONTEXT_PID:
 199                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
 200                 break;
 201         case LTTNG_EVENT_CONTEXT_PROCNAME:
 202                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
 203                 break;
 204         case LTTNG_EVENT_CONTEXT_PRIO:
 205                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
 206                 break;
 207         case LTTNG_EVENT_CONTEXT_NICE:
 208                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
 209                 break;
 210         case LTTNG_EVENT_CONTEXT_VPID:
 211                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
 212                 break;
 213         case LTTNG_EVENT_CONTEXT_TID:
 214                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
 215                 break;
 216         case LTTNG_EVENT_CONTEXT_VTID:
 217                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
 218                 break;
 219         case LTTNG_EVENT_CONTEXT_PPID:
 220                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
 221                 break;
 222         case LTTNG_EVENT_CONTEXT_VPPID:
 223                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
 224                 break;
 225         case LTTNG_EVENT_CONTEXT_HOSTNAME:
 226                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
 227                 break;
 228         case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
 229         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
 230                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
 231                 break;
 232         case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
 233                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
 234                 break;
 235         case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
 236                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
 237                 break;
 238         case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
 239                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
 240                 break;
 241         case LTTNG_EVENT_CONTEXT_MIGRATABLE:
 242                 kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
 243                 break;
 244         default:
 245                 ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
 246                 goto error;
 247         }
 248
 249         kctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
 250         kctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
 251         strncpy(kctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name,
 252                         LTTNG_SYMBOL_NAME_LEN);
 253         kctx->ctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 254
 255         if (*channel_name == '\0') {
 256                 ret = add_kctx_all_channels(ksession, kctx);
 257                 if (ret != LTTNG_OK) {
 258                         goto error;
 259                 }
 260         } else {
 261                 /* Get kernel channel */
 262                 kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
 263                 if (kchan == NULL) {
 264                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 265                         goto error;
 266                 }
 267
 268                 ret = add_kctx_to_channel(kctx, kchan);
 269                 if (ret != LTTNG_OK) {
 270                         goto error;
 271                 }
 272         }
 273
 274         return LTTNG_OK;
 275
 276 error:
 277         if (kctx) {
 278                 trace_kernel_destroy_context(kctx);
 279         }
 280         return ret;
 281 }
 282
 283 /*
 284  * Add UST context to tracer.
 285  */
 286 int context_ust_add(struct ltt_ust_session *usess,
 287                 enum lttng_domain_type domain, struct lttng_event_context *ctx,
 288                 char *channel_name)
 289 {
 290         int ret = LTTNG_OK;
 291         struct lttng_ht_iter iter;
 292         struct lttng_ht *chan_ht;
 293         struct ltt_ust_channel *uchan = NULL;
 294
 295         assert(usess);
 296         assert(ctx);
 297         assert(channel_name);
 298
 299         rcu_read_lock();
 300
 301         chan_ht = usess->domain_global.channels;
 302
 303         /* Get UST channel if defined */
 304         if (channel_name[0] != '\0') {
 305                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 306                 if (uchan == NULL) {
 307                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 308                         goto error;
 309                 }
 310         }
 311
 312         if (uchan) {
 313                 /* Add ctx to channel */
 314                 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 315         } else {
 316                 rcu_read_lock();
 317                 /* Add ctx all events, all channels */
 318                 cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
 319                         ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 320                         if (ret < 0) {
 321                                 ERR("Failed to add context to channel %s",
 322                                                 uchan->name);
 323                                 continue;
 324                         }
 325                 }
 326                 rcu_read_unlock();
 327         }
 328
 329         switch (ret) {
 330         case -EEXIST:
 331                 ret = LTTNG_ERR_UST_CONTEXT_EXIST;
 332                 break;
 333         case -ENOMEM:
 334                 ret = LTTNG_ERR_FATAL;
 335                 break;
 336         case -EINVAL:
 337                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 338                 break;
 339         case -ENOSYS:
 340                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 341                 break;
 342         default:
 343                 ret = LTTNG_OK;
 344                 break;
 345         }
 346
 347 error:
 348         rcu_read_unlock();
 349         return ret;
 350 }