src/lib/trace-ir/packet.c

   1 /*
   2  * Copyright 2016-2018 Philippe Proulx <pproulx@efficios.com>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20  * SOFTWARE.
  21  */
  22
  23 #define BT_LOG_TAG "LIB/PACKET"
  24 #include "lib/logging.h"
  25
  26 #include "lib/assert-pre.h"
  27 #include <babeltrace2/trace-ir/packet-const.h>
  28 #include <babeltrace2/trace-ir/packet.h>
  29 #include <babeltrace2/trace-ir/trace.h>
  30 #include <babeltrace2/trace-ir/stream-class.h>
  31 #include <babeltrace2/trace-ir/stream.h>
  32 #include "lib/object.h"
  33 #include "common/assert.h"
  34 #include <inttypes.h>
  35 #include <stdbool.h>
  36
  37 #include "field.h"
  38 #include "field-wrapper.h"
  39 #include "packet.h"
  40 #include "stream-class.h"
  41 #include "stream.h"
  42 #include "trace.h"
  43 #include "lib/func-status.h"
  44
  45 struct bt_stream *bt_packet_borrow_stream(struct bt_packet *packet)
  46 {
  47         BT_ASSERT_PRE_DEV_NON_NULL(packet, "Packet");
  48         return packet->stream;
  49 }
  50
  51 const struct bt_stream *bt_packet_borrow_stream_const(
  52                 const struct bt_packet *packet)
  53 {
  54         return bt_packet_borrow_stream((void *) packet);
  55 }
  56
  57 struct bt_field *bt_packet_borrow_context_field(struct bt_packet *packet)
  58 {
  59         BT_ASSERT_PRE_DEV_NON_NULL(packet, "Packet");
  60         return packet->context_field ? packet->context_field->field : NULL;
  61 }
  62
  63 const struct bt_field *bt_packet_borrow_context_field_const(
  64                 const struct bt_packet *packet)
  65 {
  66         return bt_packet_borrow_context_field((void *) packet);
  67 }
  68
  69 BT_HIDDEN
  70 void _bt_packet_set_is_frozen(const struct bt_packet *packet, bool is_frozen)
  71 {
  72         if (!packet) {
  73                 return;
  74         }
  75
  76         BT_LIB_LOGD("Setting packet's frozen state: %![packet-]+a, "
  77                 "is-frozen=%d", packet, is_frozen);
  78
  79         if (packet->context_field) {
  80                 BT_LOGD_STR("Setting packet's context field's frozen state.");
  81                 bt_field_set_is_frozen(packet->context_field->field,
  82                         is_frozen);
  83         }
  84
  85         ((struct bt_packet *) packet)->frozen = is_frozen;
  86 }
  87
  88 static inline
  89 void reset_packet(struct bt_packet *packet)
  90 {
  91         BT_ASSERT(packet);
  92         BT_LIB_LOGD("Resetting packet: %!+a", packet);
  93         bt_packet_set_is_frozen(packet, false);
  94
  95         if (packet->context_field) {
  96                 bt_field_set_is_frozen(packet->context_field->field, false);
  97                 bt_field_reset(packet->context_field->field);
  98         }
  99 }
 100
 101 static
 102 void recycle_context_field(struct bt_field_wrapper *context_field,
 103                 struct bt_stream_class *stream_class)
 104 {
 105         BT_ASSERT(context_field);
 106         BT_LIB_LOGD("Recycling packet context field: "
 107                 "addr=%p, %![sc-]+S, %![field-]+f", context_field,
 108                 stream_class, context_field->field);
 109         bt_object_pool_recycle_object(&stream_class->packet_context_field_pool,
 110                 context_field);
 111 }
 112
 113 BT_HIDDEN
 114 void bt_packet_recycle(struct bt_packet *packet)
 115 {
 116         struct bt_stream *stream;
 117
 118         BT_ASSERT(packet);
 119         BT_LIB_LOGD("Recycling packet: %!+a", packet);
 120
 121         /*
 122          * Those are the important ordered steps:
 123          *
 124          * 1. Reset the packet object (put any permanent reference it
 125          *    has, unfreeze it and its fields in developer mode, etc.),
 126          *    but do NOT put its stream's reference. This stream
 127          *    contains the pool to which we're about to recycle this
 128          *    packet object, so we must guarantee its existence thanks
 129          *    to this existing reference.
 130          *
 131          * 2. Move the stream reference to our `stream`
 132          *    variable so that we can set the packet's stream member
 133          *    to NULL before recycling it. We CANNOT do this after
 134          *    we put the stream reference because this bt_object_put_ref()
 135          *    could destroy the stream, also destroying its
 136          *    packet pool, thus also destroying our packet object (this
 137          *    would result in an invalid write access).
 138          *
 139          * 3. Recycle the packet object.
 140          *
 141          * 4. Put our stream reference.
 142          */
 143         reset_packet(packet);
 144         stream = packet->stream;
 145         BT_ASSERT(stream);
 146         packet->stream = NULL;
 147         bt_object_pool_recycle_object(&stream->packet_pool, packet);
 148         bt_object_put_ref_no_null_check(&stream->base);
 149 }
 150
 151 BT_HIDDEN
 152 void bt_packet_destroy(struct bt_packet *packet)
 153 {
 154         BT_LIB_LOGD("Destroying packet: %!+a", packet);
 155
 156         if (packet->context_field) {
 157                 if (packet->stream) {
 158                         BT_LOGD_STR("Recycling packet's context field.");
 159                         recycle_context_field(packet->context_field,
 160                                 packet->stream->class);
 161                 } else {
 162                         bt_field_wrapper_destroy(packet->context_field);
 163                 }
 164
 165                 packet->context_field = NULL;
 166         }
 167
 168         BT_LOGD_STR("Putting packet's stream.");
 169         BT_OBJECT_PUT_REF_AND_RESET(packet->stream);
 170         g_free(packet);
 171 }
 172
 173 BT_HIDDEN
 174 struct bt_packet *bt_packet_new(struct bt_stream *stream)
 175 {
 176         struct bt_packet *packet = NULL;
 177         struct bt_trace_class *trace_class = NULL;
 178
 179         BT_ASSERT(stream);
 180         BT_LIB_LOGD("Creating packet object: %![stream-]+s", stream);
 181         packet = g_new0(struct bt_packet, 1);
 182         if (!packet) {
 183                 BT_LIB_LOGE_APPEND_CAUSE(
 184                         "Failed to allocate one packet object.");
 185                 goto error;
 186         }
 187
 188         bt_object_init_shared(&packet->base,
 189                 (bt_object_release_func) bt_packet_recycle);
 190         packet->stream = stream;
 191         bt_object_get_ref_no_null_check(stream);
 192         trace_class = bt_stream_class_borrow_trace_class_inline(stream->class);
 193         BT_ASSERT(trace_class);
 194
 195         if (stream->class->packet_context_fc) {
 196                 BT_LOGD_STR("Creating initial packet context field.");
 197                 packet->context_field = bt_field_wrapper_create(
 198                         &stream->class->packet_context_field_pool,
 199                         stream->class->packet_context_fc);
 200                 if (!packet->context_field) {
 201                         BT_LIB_LOGE_APPEND_CAUSE(
 202                                 "Cannot create packet context field wrapper.");
 203                         goto error;
 204                 }
 205         }
 206
 207         BT_LIB_LOGD("Created packet object: %!+a", packet);
 208         goto end;
 209
 210 error:
 211         BT_OBJECT_PUT_REF_AND_RESET(packet);
 212
 213 end:
 214         return packet;
 215 }
 216
 217 struct bt_packet *bt_packet_create(const struct bt_stream *c_stream)
 218 {
 219         struct bt_packet *packet = NULL;
 220         struct bt_stream *stream = (void *) c_stream;
 221
 222         BT_ASSERT_PRE_NON_NULL(stream, "Stream");
 223         BT_ASSERT_PRE(stream->class->supports_packets,
 224                 "Stream class does not support packets: %![sc-]+S",
 225                 stream->class);
 226         packet = bt_object_pool_create_object(&stream->packet_pool);
 227         if (G_UNLIKELY(!packet)) {
 228                 BT_LIB_LOGE_APPEND_CAUSE(
 229                         "Cannot allocate one packet from stream's packet pool: "
 230                         "%![stream-]+s", stream);
 231                 goto end;
 232         }
 233
 234         if (G_LIKELY(!packet->stream)) {
 235                 packet->stream = stream;
 236                 bt_object_get_ref_no_null_check_no_parent_check(
 237                         &packet->stream->base);
 238         }
 239
 240 end:
 241         return (void *) packet;
 242 }
 243
 244 enum bt_packet_move_context_field_status bt_packet_move_context_field(
 245                 struct bt_packet *packet,
 246                 struct bt_packet_context_field *context_field)
 247 {
 248         struct bt_stream_class *stream_class;
 249         struct bt_field_wrapper *field_wrapper = (void *) context_field;
 250
 251         BT_ASSERT_PRE_DEV_NON_NULL(packet, "Packet");
 252         BT_ASSERT_PRE_DEV_NON_NULL(field_wrapper, "Context field");
 253         BT_ASSERT_PRE_DEV_HOT(packet, "Packet", ": %!+a", packet);
 254         stream_class = packet->stream->class;
 255         BT_ASSERT_PRE_DEV(stream_class->packet_context_fc,
 256                 "Stream class has no packet context field class: %!+S",
 257                 stream_class);
 258         BT_ASSERT_PRE_DEV(field_wrapper->field->class ==
 259                 stream_class->packet_context_fc,
 260                 "Unexpected packet context field's class: "
 261                 "%![fc-]+F, %![expected-fc-]+F", field_wrapper->field->class,
 262                 stream_class->packet_context_fc);
 263
 264         /* Recycle current context field: always exists */
 265         BT_ASSERT(packet->context_field);
 266         recycle_context_field(packet->context_field, stream_class);
 267
 268         /* Move new field */
 269         packet->context_field = field_wrapper;
 270         return BT_FUNC_STATUS_OK;
 271 }
 272
 273 void bt_packet_get_ref(const struct bt_packet *packet)
 274 {
 275         bt_object_get_ref(packet);
 276 }
 277
 278 void bt_packet_put_ref(const struct bt_packet *packet)
 279 {
 280         bt_object_put_ref(packet);
 281 }