src/lib/lttng-ust/ust-core.c

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  */
   6
   7 #define _LGPL_SOURCE
   8 #include <stdint.h>
   9 #include <stddef.h>
  10 #include <stdlib.h>
  11
  12 #include "context-internal.h"
  13 #include "lib/lttng-ust/events.h"
  14 #include "common/logging.h"
  15 #include "lttng-tracer-core.h"
  16 #include "lttng-rb-clients.h"
  17 #include "lttng-counter-client.h"
  18 #include "common/jhash.h"
  19
  20 static CDS_LIST_HEAD(lttng_transport_list);
  21 static CDS_LIST_HEAD(lttng_counter_transport_list);
  22
  23 struct lttng_transport *lttng_ust_transport_find(const char *name)
  24 {
  25         struct lttng_transport *transport;
  26
  27         cds_list_for_each_entry(transport, &lttng_transport_list, node) {
  28                 if (!strcmp(transport->name, name))
  29                         return transport;
  30         }
  31         return NULL;
  32 }
  33
  34 struct lttng_counter_transport *lttng_counter_transport_find(const char *name)
  35 {
  36         struct lttng_counter_transport *transport;
  37
  38         cds_list_for_each_entry(transport, &lttng_counter_transport_list, node) {
  39                 if (!strcmp(transport->name, name))
  40                         return transport;
  41         }
  42         return NULL;
  43 }
  44
  45 /**
  46  * lttng_transport_register - LTT transport registration
  47  * @transport: transport structure
  48  *
  49  * Registers a transport which can be used as output to extract the data out of
  50  * LTTng. Called with ust_lock held.
  51  */
  52 void lttng_transport_register(struct lttng_transport *transport)
  53 {
  54         cds_list_add_tail(&transport->node, &lttng_transport_list);
  55 }
  56
  57 /**
  58  * lttng_transport_unregister - LTT transport unregistration
  59  * @transport: transport structure
  60  * Called with ust_lock held.
  61  */
  62 void lttng_transport_unregister(struct lttng_transport *transport)
  63 {
  64         cds_list_del(&transport->node);
  65 }
  66
  67 /**
  68  * lttng_counter_transport_register - LTTng counter transport registration
  69  * @transport: transport structure
  70  *
  71  * Registers a counter transport which can be used as output to extract
  72  * the data out of LTTng. Called with ust_lock held.
  73  */
  74 void lttng_counter_transport_register(struct lttng_counter_transport *transport)
  75 {
  76         cds_list_add_tail(&transport->node, &lttng_counter_transport_list);
  77 }
  78
  79 /**
  80  * lttng_counter_transport_unregister - LTTng counter transport unregistration
  81  * @transport: transport structure
  82  * Called with ust_lock held.
  83  */
  84 void lttng_counter_transport_unregister(struct lttng_counter_transport *transport)
  85 {
  86         cds_list_del(&transport->node);
  87 }
  88
  89 size_t lttng_ust_dummy_get_size(void *priv __attribute__((unused)),
  90                 struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)),
  91                 size_t offset)
  92 {
  93         size_t size = 0;
  94
  95         size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(char));
  96         size += sizeof(char);           /* tag */
  97         return size;
  98 }
  99
 100 void lttng_ust_dummy_record(void *priv __attribute__((unused)),
 101                 struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)),
 102                 struct lttng_ust_ring_buffer_ctx *ctx,
 103                 struct lttng_ust_channel_buffer *chan)
 104 {
 105         char sel_char = (char) LTTNG_UST_DYNAMIC_TYPE_NONE;
 106
 107         chan->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(sel_char));
 108 }
 109
 110 void lttng_ust_dummy_get_value(void *priv __attribute__((unused)),
 111                 struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)),
 112                 struct lttng_ust_ctx_value *value)
 113 {
 114         value->sel = LTTNG_UST_DYNAMIC_TYPE_NONE;
 115 }
 116
 117 int lttng_context_is_app(const char *name)
 118 {
 119         if (strncmp(name, "$app.", strlen("$app.")) != 0) {
 120                 return 0;
 121         }
 122         return 1;
 123 }
 124
 125 struct lttng_ust_channel_buffer *lttng_ust_alloc_channel_buffer(void)
 126 {
 127         struct lttng_ust_channel_buffer *lttng_chan_buf;
 128         struct lttng_ust_channel_common *lttng_chan_common;
 129         struct lttng_ust_channel_buffer_private *lttng_chan_buf_priv;
 130
 131         lttng_chan_buf = zmalloc(sizeof(struct lttng_ust_channel_buffer));
 132         if (!lttng_chan_buf)
 133                 goto lttng_chan_buf_error;
 134         lttng_chan_buf->struct_size = sizeof(struct lttng_ust_channel_buffer);
 135         lttng_chan_common = zmalloc(sizeof(struct lttng_ust_channel_common));
 136         if (!lttng_chan_common)
 137                 goto lttng_chan_common_error;
 138         lttng_chan_common->struct_size = sizeof(struct lttng_ust_channel_common);
 139         lttng_chan_buf_priv = zmalloc(sizeof(struct lttng_ust_channel_buffer_private));
 140         if (!lttng_chan_buf_priv)
 141                 goto lttng_chan_buf_priv_error;
 142         lttng_chan_buf->parent = lttng_chan_common;
 143         lttng_chan_common->type = LTTNG_UST_CHANNEL_TYPE_BUFFER;
 144         lttng_chan_common->child = lttng_chan_buf;
 145         lttng_chan_buf->priv = lttng_chan_buf_priv;
 146         lttng_chan_common->priv = &lttng_chan_buf_priv->parent;
 147         lttng_chan_buf_priv->pub = lttng_chan_buf;
 148         lttng_chan_buf_priv->parent.pub = lttng_chan_common;
 149
 150         return lttng_chan_buf;
 151
 152 lttng_chan_buf_priv_error:
 153         free(lttng_chan_common);
 154 lttng_chan_common_error:
 155         free(lttng_chan_buf);
 156 lttng_chan_buf_error:
 157         return NULL;
 158 }
 159
 160 void lttng_ust_free_channel_common(struct lttng_ust_channel_common *chan)
 161 {
 162         switch (chan->type) {
 163         case LTTNG_UST_CHANNEL_TYPE_BUFFER:
 164         {
 165                 struct lttng_ust_channel_buffer *chan_buf;
 166
 167                 chan_buf = (struct lttng_ust_channel_buffer *)chan->child;
 168                 free(chan_buf->parent);
 169                 free(chan_buf->priv);
 170                 free(chan_buf);
 171                 break;
 172         }
 173         default:
 174                 abort();
 175         }
 176 }
 177
 178 void lttng_ust_ring_buffer_clients_init(void)
 179 {
 180         lttng_ring_buffer_metadata_client_init();
 181         lttng_ring_buffer_client_overwrite_init();
 182         lttng_ring_buffer_client_overwrite_rt_init();
 183         lttng_ring_buffer_client_discard_init();
 184         lttng_ring_buffer_client_discard_rt_init();
 185 }
 186
 187 void lttng_ust_ring_buffer_clients_exit(void)
 188 {
 189         lttng_ring_buffer_client_discard_rt_exit();
 190         lttng_ring_buffer_client_discard_exit();
 191         lttng_ring_buffer_client_overwrite_rt_exit();
 192         lttng_ring_buffer_client_overwrite_exit();
 193         lttng_ring_buffer_metadata_client_exit();
 194 }
 195
 196 void lttng_ust_counter_clients_init(void)
 197 {
 198         lttng_counter_client_percpu_64_modular_init();
 199         lttng_counter_client_percpu_32_modular_init();
 200 }
 201
 202 void lttng_ust_counter_clients_exit(void)
 203 {
 204         lttng_counter_client_percpu_32_modular_exit();
 205         lttng_counter_client_percpu_64_modular_exit();
 206 }