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.h>
  28 #include <babeltrace2/trace-ir/trace.h>
  29 #include <babeltrace2/trace-ir/stream-class.h>
  30 #include <babeltrace2/trace-ir/stream.h>
  31 #include "lib/object.h"
  32 #include "common/assert.h"
  33 #include <inttypes.h>
  34 #include <stdbool.h>
  35
  36 #include "field.h"
  37 #include "field-wrapper.h"
  38 #include "packet.h"
  39 #include "stream-class.h"
  40 #include "stream.h"
  41 #include "trace.h"
  42 #include "lib/func-status.h"
  43
  44 struct bt_stream *bt_packet_borrow_stream(struct bt_packet *packet)
  45 {
  46         BT_ASSERT_PRE_DEV_NON_NULL(packet, "Packet");
  47         return packet->stream;
  48 }
  49
  50 const struct bt_stream *bt_packet_borrow_stream_const(
  51                 const struct bt_packet *packet)
  52 {
  53         return bt_packet_borrow_stream((void *) packet);
  54 }
  55
  56 struct bt_field *bt_packet_borrow_context_field(struct bt_packet *packet)
  57 {
  58         BT_ASSERT_PRE_DEV_NON_NULL(packet, "Packet");
  59         return packet->context_field ? packet->context_field->field : NULL;
  60 }
  61
  62 const struct bt_field *bt_packet_borrow_context_field_const(
  63                 const struct bt_packet *packet)
  64 {
  65         return bt_packet_borrow_context_field((void *) packet);
  66 }
  67
  68 BT_HIDDEN
  69 void _bt_packet_set_is_frozen(const struct bt_packet *packet, bool is_frozen)
  70 {
  71         if (!packet) {
  72                 return;
  73         }
  74
  75         BT_LIB_LOGD("Setting packet's frozen state: %![packet-]+a, "
  76                 "is-frozen=%d", packet, is_frozen);
  77
  78         if (packet->context_field) {
  79                 BT_LOGD_STR("Setting packet's context field's frozen state.");
  80                 bt_field_set_is_frozen(packet->context_field->field,
  81                         is_frozen);
  82         }
  83
  84         ((struct bt_packet *) packet)->frozen = is_frozen;
  85 }
  86
  87 static inline
  88 void reset_packet(struct bt_packet *packet)
  89 {
  90         BT_ASSERT(packet);
  91         BT_LIB_LOGD("Resetting packet: %!+a", packet);
  92         bt_packet_set_is_frozen(packet, false);
  93
  94         if (packet->context_field) {
  95                 bt_field_set_is_frozen(packet->context_field->field, false);
  96                 bt_field_reset(packet->context_field->field);
  97         }
  98 }
  99
 100 static
 101 void recycle_context_field(struct bt_field_wrapper *context_field,
 102                 struct bt_stream_class *stream_class)
 103 {
 104         BT_ASSERT(context_field);
 105         BT_LIB_LOGD("Recycling packet context field: "
 106                 "addr=%p, %![sc-]+S, %![field-]+f", context_field,
 107                 stream_class, context_field->field);
 108         bt_object_pool_recycle_object(&stream_class->packet_context_field_pool,
 109                 context_field);
 110 }
 111
 112 BT_HIDDEN
 113 void bt_packet_recycle(struct bt_packet *packet)
 114 {
 115         struct bt_stream *stream;
 116
 117         BT_ASSERT(packet);
 118         BT_LIB_LOGD("Recycling packet: %!+a", packet);
 119
 120         /*
 121          * Those are the important ordered steps:
 122          *
 123          * 1. Reset the packet object (put any permanent reference it
 124          *    has, unfreeze it and its fields in developer mode, etc.),
 125          *    but do NOT put its stream's reference. This stream
 126          *    contains the pool to which we're about to recycle this
 127          *    packet object, so we must guarantee its existence thanks
 128          *    to this existing reference.
 129          *
 130          * 2. Move the stream reference to our `stream`
 131          *    variable so that we can set the packet's stream member
 132          *    to NULL before recycling it. We CANNOT do this after
 133          *    we put the stream reference because this bt_object_put_ref()
 134          *    could destroy the stream, also destroying its
 135          *    packet pool, thus also destroying our packet object (this
 136          *    would result in an invalid write access).
 137          *
 138          * 3. Recycle the packet object.
 139          *
 140          * 4. Put our stream reference.
 141          */
 142         reset_packet(packet);
 143         stream = packet->stream;
 144         BT_ASSERT(stream);
 145         packet->stream = NULL;
 146         bt_object_pool_recycle_object(&stream->packet_pool, packet);
 147         bt_object_put_ref_no_null_check(&stream->base);
 148 }
 149
 150 BT_HIDDEN
 151 void bt_packet_destroy(struct bt_packet *packet)
 152 {
 153         BT_LIB_LOGD("Destroying packet: %!+a", packet);
 154
 155         if (packet->context_field) {
 156                 if (packet->stream) {
 157                         BT_LOGD_STR("Recycling packet's context field.");
 158                         recycle_context_field(packet->context_field,
 159                                 packet->stream->class);
 160                 } else {
 161                         bt_field_wrapper_destroy(packet->context_field);
 162                 }
 163
 164                 packet->context_field = NULL;
 165         }
 166
 167         BT_LOGD_STR("Putting packet's stream.");
 168         BT_OBJECT_PUT_REF_AND_RESET(packet->stream);
 169         g_free(packet);
 170 }
 171
 172 BT_HIDDEN
 173 struct bt_packet *bt_packet_new(struct bt_stream *stream)
 174 {
 175         struct bt_packet *packet = NULL;
 176         struct bt_trace_class *trace_class = NULL;
 177
 178         BT_ASSERT(stream);
 179         BT_LIB_LOGD("Creating packet object: %![stream-]+s", stream);
 180         packet = g_new0(struct bt_packet, 1);
 181         if (!packet) {
 182                 BT_LIB_LOGE_APPEND_CAUSE(
 183                         "Failed to allocate one packet object.");
 184                 goto error;
 185         }
 186
 187         bt_object_init_shared(&packet->base,
 188                 (bt_object_release_func) bt_packet_recycle);
 189         packet->stream = stream;
 190         bt_object_get_ref_no_null_check(stream);
 191         trace_class = bt_stream_class_borrow_trace_class_inline(stream->class);
 192         BT_ASSERT(trace_class);
 193
 194         if (stream->class->packet_context_fc) {
 195                 BT_LOGD_STR("Creating initial packet context field.");
 196                 packet->context_field = bt_field_wrapper_create(
 197                         &stream->class->packet_context_field_pool,
 198                         stream->class->packet_context_fc);
 199                 if (!packet->context_field) {
 200                         BT_LIB_LOGE_APPEND_CAUSE(
 201                                 "Cannot create packet context field wrapper.");
 202                         goto error;
 203                 }
 204         }
 205
 206         BT_LIB_LOGD("Created packet object: %!+a", packet);
 207         goto end;
 208
 209 error:
 210         BT_OBJECT_PUT_REF_AND_RESET(packet);
 211
 212 end:
 213         return packet;
 214 }
 215
 216 struct bt_packet *bt_packet_create(const struct bt_stream *c_stream)
 217 {
 218         struct bt_packet *packet = NULL;
 219         struct bt_stream *stream = (void *) c_stream;
 220
 221         BT_ASSERT_PRE_NO_ERROR();
 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 void bt_packet_get_ref(const struct bt_packet *packet)
 245 {
 246         bt_object_get_ref(packet);
 247 }
 248
 249 void bt_packet_put_ref(const struct bt_packet *packet)
 250 {
 251         bt_object_put_ref(packet);
 252 }