Consumer: Implement lttng_consumer_clear_channel
[lttng-tools.git] / src / common / consumer / consumer.c
index 567babadf177ade2912666c2a14ec0ee368ea7d2..3e3c304873bad94c005cfa5a611c46ccc4ce716e 100644 (file)
@@ -3550,34 +3550,6 @@ error_nosignal:
        }
 }
 
-/*
- * Try to lock the stream mutex.
- *
- * On success, 1 is returned else 0 indicating that the mutex is NOT lock.
- */
-static int stream_try_lock(struct lttng_consumer_stream *stream)
-{
-       int ret;
-
-       assert(stream);
-
-       /*
-        * Try to lock the stream mutex. On failure, we know that the stream is
-        * being used else where hence there is data still being extracted.
-        */
-       ret = pthread_mutex_trylock(&stream->lock);
-       if (ret) {
-               /* For both EBUSY and EINVAL error, the mutex is NOT locked. */
-               ret = 0;
-               goto end;
-       }
-
-       ret = 1;
-
-end:
-       return ret;
-}
-
 /*
  * Search for a relayd associated to the session id and return the reference.
  *
@@ -3644,30 +3616,11 @@ int consumer_data_pending(uint64_t id)
        /* Ease our life a bit */
        ht = consumer_data.stream_list_ht;
 
-       relayd = find_relayd_by_session_id(id);
-       if (relayd) {
-               /* Send init command for data pending. */
-               pthread_mutex_lock(&relayd->ctrl_sock_mutex);
-               ret = relayd_begin_data_pending(&relayd->control_sock,
-                               relayd->relayd_session_id);
-               pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
-               if (ret < 0) {
-                       /* Communication error thus the relayd so no data pending. */
-                       ERR("Relayd begin data pending failed. Cleaning up relayd %" PRIu64".", relayd->net_seq_idx);
-                       lttng_consumer_cleanup_relayd(relayd);
-                       goto data_not_pending;
-               }
-       }
-
        cds_lfht_for_each_entry_duplicate(ht->ht,
                        ht->hash_fct(&id, lttng_ht_seed),
                        ht->match_fct, &id,
                        &iter.iter, stream, node_session_id.node) {
-               /* If this call fails, the stream is being used hence data pending. */
-               ret = stream_try_lock(stream);
-               if (!ret) {
-                       goto data_pending;
-               }
+               pthread_mutex_lock(&stream->lock);
 
                /*
                 * A removed node from the hash table indicates that the stream has
@@ -3685,9 +3638,27 @@ int consumer_data_pending(uint64_t id)
                        }
                }
 
-               /* Relayd check */
-               if (relayd) {
-                       pthread_mutex_lock(&relayd->ctrl_sock_mutex);
+               pthread_mutex_unlock(&stream->lock);
+       }
+
+       relayd = find_relayd_by_session_id(id);
+       if (relayd) {
+               unsigned int is_data_inflight = 0;
+
+               /* Send init command for data pending. */
+               pthread_mutex_lock(&relayd->ctrl_sock_mutex);
+               ret = relayd_begin_data_pending(&relayd->control_sock,
+                               relayd->relayd_session_id);
+               if (ret < 0) {
+                       pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
+                       /* Communication error thus the relayd so no data pending. */
+                       goto data_not_pending;
+               }
+
+               cds_lfht_for_each_entry_duplicate(ht->ht,
+                               ht->hash_fct(&id, lttng_ht_seed),
+                               ht->match_fct, &id,
+                               &iter.iter, stream, node_session_id.node) {
                        if (stream->metadata_flag) {
                                ret = relayd_quiescent_control(&relayd->control_sock,
                                                stream->relayd_stream_id);
@@ -3696,27 +3667,19 @@ int consumer_data_pending(uint64_t id)
                                                stream->relayd_stream_id,
                                                stream->next_net_seq_num - 1);
                        }
-                       if (ret < 0) {
+
+                       if (ret == 1) {
+                               pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
+                               goto data_pending;
+                       } else if (ret < 0) {
                                ERR("Relayd data pending failed. Cleaning up relayd %" PRIu64".", relayd->net_seq_idx);
                                lttng_consumer_cleanup_relayd(relayd);
                                pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
-                               pthread_mutex_unlock(&stream->lock);
                                goto data_not_pending;
                        }
-                       pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
-                       if (ret == 1) {
-                               pthread_mutex_unlock(&stream->lock);
-                               goto data_pending;
-                       }
                }
-               pthread_mutex_unlock(&stream->lock);
-       }
 
-       if (relayd) {
-               unsigned int is_data_inflight = 0;
-
-               /* Send init command for data pending. */
-               pthread_mutex_lock(&relayd->ctrl_sock_mutex);
+               /* Send end command for data pending. */
                ret = relayd_end_data_pending(&relayd->control_sock,
                                relayd->relayd_session_id, &is_data_inflight);
                pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
@@ -3804,3 +3767,134 @@ unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos,
        }
        return start_pos;
 }
+
+static
+int consumer_flush_buffer(struct lttng_consumer_stream *stream, int producer_active)
+{
+       int ret = 0;
+
+       switch (consumer_data.type) {
+       case LTTNG_CONSUMER_KERNEL:
+               ret = kernctl_buffer_flush(stream->wait_fd);
+               if (ret < 0) {
+                       ERR("Failed to flush kernel stream");
+                       goto end;
+               }
+               break;
+       case LTTNG_CONSUMER32_UST:
+       case LTTNG_CONSUMER64_UST:
+               lttng_ustconsumer_flush_buffer(stream, producer_active);
+               break;
+       default:
+               ERR("Unknown consumer_data type");
+               abort();
+       }
+
+end:
+       return ret;
+}
+
+static
+int consumer_clear_buffer(struct lttng_consumer_stream *stream)
+{
+       int ret = 0;
+
+       switch (consumer_data.type) {
+       case LTTNG_CONSUMER_KERNEL:
+               ret = kernctl_buffer_clear(stream->wait_fd);
+               if (ret < 0) {
+                       ERR("Failed to flush kernel stream");
+                       goto end;
+               }
+               break;
+       case LTTNG_CONSUMER32_UST:
+       case LTTNG_CONSUMER64_UST:
+               lttng_ustconsumer_clear_buffer(stream);
+               break;
+       default:
+               ERR("Unknown consumer_data type");
+               abort();
+       }
+
+end:
+       return ret;
+}
+
+static
+int clear_unmonitored_channel(struct lttng_consumer_channel *channel)
+{
+
+       int ret;
+       struct lttng_consumer_stream *stream;
+
+       assert(!channel->monitor);
+       assert(channel->type != CONSUMER_CHANNEL_TYPE_METADATA);
+
+       rcu_read_lock();
+       pthread_mutex_lock(&channel->lock);
+       cds_list_for_each_entry(stream, &channel->streams.head, send_node) {
+               health_code_update();
+               pthread_mutex_lock(&stream->lock);
+
+               ret = consumer_flush_buffer(stream, 1);
+               if (ret < 0) {
+                       ERR("Failed to flush stream %" PRIu64 " during channel clear",
+                                       stream->key);
+                       ret = LTTCOMM_CONSUMERD_FATAL;
+                       goto error_unlock;
+               }
+
+               ret = consumer_clear_buffer(stream);
+               if (ret < 0) {
+                       ERR("Failed to clear stream %" PRIu64 " during channel clear",
+                                       stream->key);
+                       ret = LTTCOMM_CONSUMERD_FATAL;
+                       goto error_unlock;
+               }
+               pthread_mutex_unlock(&stream->lock);
+       }
+       pthread_mutex_unlock(&channel->lock);
+       rcu_read_unlock();
+       return 0;
+
+error_unlock:
+       pthread_mutex_unlock(&stream->lock);
+       pthread_mutex_unlock(&channel->lock);
+       rcu_read_unlock();
+       return ret;
+}
+
+int lttng_consumer_clear_channel(struct lttng_consumer_channel *channel)
+{
+       int ret;
+
+       DBG("Consumer clear channel %" PRIu64, channel->key);
+
+       if (!channel->monitor) {
+               /* Snapshot mode */
+               if (channel->type == CONSUMER_CHANNEL_TYPE_METADATA) {
+                       /*
+                        * Nothing to do for the metadata channel/stream.
+                        * Snapshot mechanism already take care of the metadata
+                        * handling/generation.
+                        */
+                       goto end;
+               }
+               ret = clear_unmonitored_channel(channel);
+               if (ret) {
+                       goto error;
+               }
+       } else {
+               /* TODO:
+                * Normal channel and relayd bound clear operation not supported
+                * for now
+                */
+               ret = LTTCOMM_CONSUMERD_FATAL;
+               goto error;
+       }
+
+end:
+       ret = LTTCOMM_CONSUMERD_SUCCESS;
+error:
+       return ret;
+}
This page took 0.029623 seconds and 5 git commands to generate.