src/bin/lttng-sessiond/context.c

   1 /*
   2  * Copyright (C)  2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <unistd.h>
  23 #include <urcu/list.h>
  24
  25 #include <common/error.h>
  26 #include <common/sessiond-comm/sessiond-comm.h>
  27
  28 #include "context.h"
  29 #include "kernel.h"
  30 #include "ust-app.h"
  31 #include "trace-ust.h"
  32
  33 /*
  34  * Add kernel context to all channel.
  35  */
  36 static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
  37                 struct lttng_kernel_context *kctx)
  38 {
  39         int ret;
  40         struct ltt_kernel_channel *kchan;
  41
  42         DBG("Adding kernel context to all channels");
  43
  44         /* Go over all channels */
  45         cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
  46                 ret = kernel_add_channel_context(kchan, kctx);
  47                 if (ret < 0) {
  48                         ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
  49                         goto error;
  50                 }
  51         }
  52
  53         ret = LTTNG_OK;
  54
  55 error:
  56         return ret;
  57 }
  58
  59 /*
  60  * Add kernel context to a specific channel.
  61  */
  62 static int add_kctx_to_channel(struct lttng_kernel_context *kctx,
  63                 struct ltt_kernel_channel *kchan)
  64 {
  65         int ret;
  66
  67         DBG("Add kernel context to channel '%s'", kchan->channel->name);
  68
  69         ret = kernel_add_channel_context(kchan, kctx);
  70         if (ret < 0) {
  71                 ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
  72                 goto error;
  73         }
  74
  75         ret = LTTNG_OK;
  76
  77 error:
  78         return ret;
  79 }
  80
  81 /*
  82  * Add UST context to channel.
  83  */
  84 static int add_uctx_to_channel(struct ltt_ust_session *usess, int domain,
  85                 struct ltt_ust_channel *uchan, struct lttng_event_context *ctx)
  86 {
  87         int ret;
  88         struct ltt_ust_context *uctx;
  89         struct lttng_ht_iter iter;
  90         struct lttng_ht_node_ulong *uctx_node;
  91
  92         /* Create ltt UST context */
  93         uctx = trace_ust_create_context(ctx);
  94         if (uctx == NULL) {
  95                 ret = -EINVAL;
  96                 goto error;
  97         }
  98
  99         switch (domain) {
 100         case LTTNG_DOMAIN_UST:
 101                 ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
 102                 if (ret < 0) {
 103                         goto error;
 104                 }
 105                 break;
 106         default:
 107                 ret = -ENOSYS;
 108                 goto error;
 109         }
 110
 111         /* Lookup context before adding it */
 112         lttng_ht_lookup(uchan->ctx, (void *)((unsigned long)uctx->ctx.ctx), &iter);
 113         uctx_node = lttng_ht_iter_get_node_ulong(&iter);
 114         if (uctx_node != NULL) {
 115                 ret = -EEXIST;
 116                 goto error;
 117         }
 118
 119         /* Add ltt UST context node to ltt UST channel */
 120         lttng_ht_add_unique_ulong(uchan->ctx, &uctx->node);
 121
 122         DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 123
 124         return 0;
 125
 126 error:
 127         free(uctx);
 128         return ret;
 129 }
 130
 131 /*
 132  * Add kernel context to tracer.
 133  */
 134 int context_kernel_add(struct ltt_kernel_session *ksession,
 135                 struct lttng_event_context *ctx, char *channel_name)
 136 {
 137         int ret;
 138         struct ltt_kernel_channel *kchan;
 139         struct lttng_kernel_context kctx;
 140
 141         /* Setup kernel context structure */
 142         switch (ctx->ctx) {
 143         case LTTNG_EVENT_CONTEXT_PID:
 144                 kctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
 145                 break;
 146         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
 147                 kctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_COUNTER;
 148                 break;
 149         case LTTNG_EVENT_CONTEXT_PROCNAME:
 150                 kctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
 151                 break;
 152         case LTTNG_EVENT_CONTEXT_PRIO:
 153                 kctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
 154                 break;
 155         case LTTNG_EVENT_CONTEXT_NICE:
 156                 kctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
 157                 break;
 158         case LTTNG_EVENT_CONTEXT_VPID:
 159                 kctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
 160                 break;
 161         case LTTNG_EVENT_CONTEXT_TID:
 162                 kctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
 163                 break;
 164         case LTTNG_EVENT_CONTEXT_VTID:
 165                 kctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
 166                 break;
 167         case LTTNG_EVENT_CONTEXT_PPID:
 168                 kctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
 169                 break;
 170         case LTTNG_EVENT_CONTEXT_VPPID:
 171                 kctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
 172                 break;
 173         case LTTNG_EVENT_CONTEXT_HOSTNAME:
 174                 kctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
 175                 break;
 176         default:
 177                 return LTTNG_ERR_KERN_CONTEXT_FAIL;
 178         }
 179
 180         kctx.u.perf_counter.type = ctx->u.perf_counter.type;
 181         kctx.u.perf_counter.config = ctx->u.perf_counter.config;
 182         strncpy(kctx.u.perf_counter.name, ctx->u.perf_counter.name,
 183                         LTTNG_SYMBOL_NAME_LEN);
 184         kctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 185
 186         if (strlen(channel_name) == 0) {
 187                 ret = add_kctx_all_channels(ksession, &kctx);
 188                 if (ret != LTTNG_OK) {
 189                         goto error;
 190                 }
 191         } else {
 192                 /* Get kernel channel */
 193                 kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
 194                 if (kchan == NULL) {
 195                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 196                         goto error;
 197                 }
 198
 199                 ret = add_kctx_to_channel(&kctx, kchan);
 200                 if (ret != LTTNG_OK) {
 201                         goto error;
 202                 }
 203         }
 204
 205         ret = LTTNG_OK;
 206
 207 error:
 208         return ret;
 209 }
 210
 211 /*
 212  * Add UST context to tracer.
 213  */
 214 int context_ust_add(struct ltt_ust_session *usess, int domain,
 215                 struct lttng_event_context *ctx, char *channel_name)
 216 {
 217         int ret = LTTNG_OK;
 218         struct lttng_ht_iter iter;
 219         struct lttng_ht *chan_ht;
 220         struct ltt_ust_channel *uchan = NULL;
 221
 222         /*
 223          * Define which channel's hashtable to use from the domain or quit if
 224          * unknown domain.
 225          */
 226         switch (domain) {
 227         case LTTNG_DOMAIN_UST:
 228                 chan_ht = usess->domain_global.channels;
 229                 break;
 230 #if 0
 231         case LTTNG_DOMAIN_UST_EXEC_NAME:
 232         case LTTNG_DOMAIN_UST_PID:
 233         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
 234 #endif
 235         default:
 236                 ret = LTTNG_ERR_UND;
 237                 goto error;
 238         }
 239
 240         /* Get UST channel if defined */
 241         if (strlen(channel_name) != 0) {
 242                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 243                 if (uchan == NULL) {
 244                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 245                         goto error;
 246                 }
 247         }
 248
 249         if (uchan) {
 250                 /* Add ctx to channel */
 251                 ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 252         } else {
 253                 /* Add ctx all events, all channels */
 254                 cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
 255                         ret = add_uctx_to_channel(usess, domain, uchan, ctx);
 256                         if (ret < 0) {
 257                                 ERR("Context failed for channel %s", uchan->name);
 258                                 continue;
 259                         }
 260                 }
 261         }
 262
 263         switch (ret) {
 264         case -EEXIST:
 265                 ret = LTTNG_ERR_UST_CONTEXT_EXIST;
 266                 break;
 267         case -ENOMEM:
 268                 ret = LTTNG_ERR_FATAL;
 269                 break;
 270         case -EINVAL:
 271                 ret = LTTNG_ERR_UST_CONTEXT_INVAL;
 272                 break;
 273         case -ENOSYS:
 274                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 275                 break;
 276         default:
 277                 ret = LTTNG_OK;
 278                 break;
 279         }
 280
 281 error:
 282         return ret;
 283 }