.type = LTTNG_CONSUMER_UNKNOWN,
};
-/* timeout parameter, to control the polling thread grace period. */
-int consumer_poll_timeout = -1;
-
/*
* Flag to inform the polling thread to quit when all fd hung up. Updated by
* the consumer_thread_receive_fds when it notices that all fds has hung up.
volatile int consumer_quit;
/*
- * The following two hash tables are visible by all threads which are separated
- * in different source files.
- *
* Global hash table containing respectively metadata and data streams. The
* stream element in this ht should only be updated by the metadata poll thread
* for the metadata and the data poll thread for the data.
*/
-struct lttng_ht *metadata_ht;
-struct lttng_ht *data_ht;
+static struct lttng_ht *metadata_ht;
+static struct lttng_ht *data_ht;
+
+/*
+ * Notify a thread pipe to poll back again. This usually means that some global
+ * state has changed so we just send back the thread in a poll wait call.
+ */
+static void notify_thread_pipe(int wpipe)
+{
+ int ret;
+
+ do {
+ struct lttng_consumer_stream *null_stream = NULL;
+
+ ret = write(wpipe, &null_stream, sizeof(null_stream));
+ } while (ret < 0 && errno == EINTR);
+}
/*
* Find a stream. The consumer_data.lock must be locked during this
rcu_read_unlock();
}
+/*
+ * Return a channel object for the given key.
+ *
+ * RCU read side lock MUST be acquired before calling this function and
+ * protects the channel ptr.
+ */
static struct lttng_consumer_channel *consumer_find_channel(int key)
{
struct lttng_ht_iter iter;
return NULL;
}
- rcu_read_lock();
-
lttng_ht_lookup(consumer_data.channel_ht, (void *)((unsigned long) key),
&iter);
node = lttng_ht_iter_get_node_ulong(&iter);
channel = caa_container_of(node, struct lttng_consumer_channel, node);
}
- rcu_read_unlock();
-
return channel;
}
struct consumer_relayd_sock_pair *relayd =
caa_container_of(node, struct consumer_relayd_sock_pair, node);
+ /*
+ * Close all sockets. This is done in the call RCU since we don't want the
+ * socket fds to be reassigned thus potentially creating bad state of the
+ * relayd object.
+ *
+ * We do not have to lock the control socket mutex here since at this stage
+ * there is no one referencing to this relayd object.
+ */
+ (void) relayd_close(&relayd->control_sock);
+ (void) relayd_close(&relayd->data_sock);
+
free(relayd);
}
iter.iter.node = &relayd->node.node;
ret = lttng_ht_del(consumer_data.relayd_ht, &iter);
if (ret != 0) {
- /* We assume the relayd was already destroyed */
+ /* We assume the relayd is being or is destroyed */
return;
}
- /* Close all sockets */
- pthread_mutex_lock(&relayd->ctrl_sock_mutex);
- (void) relayd_close(&relayd->control_sock);
- pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
- (void) relayd_close(&relayd->data_sock);
-
/* RCU free() call */
call_rcu(&relayd->node.head, consumer_rcu_free_relayd);
}
+/*
+ * Iterate over the relayd hash table and destroy each element. Finally,
+ * destroy the whole hash table.
+ */
+static void cleanup_relayd_ht(void)
+{
+ struct lttng_ht_iter iter;
+ struct consumer_relayd_sock_pair *relayd;
+
+ rcu_read_lock();
+
+ cds_lfht_for_each_entry(consumer_data.relayd_ht->ht, &iter.iter, relayd,
+ node.node) {
+ destroy_relayd(relayd);
+ }
+
+ lttng_ht_destroy(consumer_data.relayd_ht);
+
+ rcu_read_unlock();
+}
+
+/*
+ * Update the end point status of all streams having the given network sequence
+ * index (relayd index).
+ *
+ * It's atomically set without having the stream mutex locked which is fine
+ * because we handle the write/read race with a pipe wakeup for each thread.
+ */
+static void update_endpoint_status_by_netidx(int net_seq_idx,
+ enum consumer_endpoint_status status)
+{
+ struct lttng_ht_iter iter;
+ struct lttng_consumer_stream *stream;
+
+ DBG("Consumer set delete flag on stream by idx %d", net_seq_idx);
+
+ rcu_read_lock();
+
+ /* Let's begin with metadata */
+ cds_lfht_for_each_entry(metadata_ht->ht, &iter.iter, stream, node.node) {
+ if (stream->net_seq_idx == net_seq_idx) {
+ uatomic_set(&stream->endpoint_status, status);
+ DBG("Delete flag set to metadata stream %d", stream->wait_fd);
+ }
+ }
+
+ /* Follow up by the data streams */
+ cds_lfht_for_each_entry(data_ht->ht, &iter.iter, stream, node.node) {
+ if (stream->net_seq_idx == net_seq_idx) {
+ uatomic_set(&stream->endpoint_status, status);
+ DBG("Delete flag set to data stream %d", stream->wait_fd);
+ }
+ }
+ rcu_read_unlock();
+}
+
+/*
+ * Cleanup a relayd object by flagging every associated streams for deletion,
+ * destroying the object meaning removing it from the relayd hash table,
+ * closing the sockets and freeing the memory in a RCU call.
+ *
+ * If a local data context is available, notify the threads that the streams'
+ * state have changed.
+ */
+static void cleanup_relayd(struct consumer_relayd_sock_pair *relayd,
+ struct lttng_consumer_local_data *ctx)
+{
+ int netidx;
+
+ assert(relayd);
+
+ DBG("Cleaning up relayd sockets");
+
+ /* Save the net sequence index before destroying the object */
+ netidx = relayd->net_seq_idx;
+
+ /*
+ * Delete the relayd from the relayd hash table, close the sockets and free
+ * the object in a RCU call.
+ */
+ destroy_relayd(relayd);
+
+ /* Set inactive endpoint to all streams */
+ update_endpoint_status_by_netidx(netidx, CONSUMER_ENDPOINT_INACTIVE);
+
+ /*
+ * With a local data context, notify the threads that the streams' state
+ * have changed. The write() action on the pipe acts as an "implicit"
+ * memory barrier ordering the updates of the end point status from the
+ * read of this status which happens AFTER receiving this notify.
+ */
+ if (ctx) {
+ notify_thread_pipe(ctx->consumer_data_pipe[1]);
+ notify_thread_pipe(ctx->consumer_metadata_pipe[1]);
+ }
+}
+
/*
* Flag a relayd socket pair for destruction. Destroy it if the refcount
* reaches zero.
assert(stream);
+ DBG("Consumer del stream %d", stream->wait_fd);
+
if (ht == NULL) {
/* Means the stream was allocated but not successfully added */
goto free_stream;
}
pthread_mutex_lock(&consumer_data.lock);
+ pthread_mutex_lock(&stream->lock);
switch (consumer_data.type) {
case LTTNG_CONSUMER_KERNEL:
end:
consumer_data.need_update = 1;
+ pthread_mutex_unlock(&stream->lock);
pthread_mutex_unlock(&consumer_data.lock);
if (free_chan) {
goto end;
}
+ rcu_read_lock();
+
/*
* Get stream's channel reference. Needed when adding the stream to the
* global hash table.
stream->path_name, stream->key, stream->shm_fd, stream->wait_fd,
(unsigned long long) stream->mmap_len, stream->out_fd,
stream->net_seq_idx, stream->session_id);
+
+ rcu_read_unlock();
return stream;
error:
+ rcu_read_unlock();
free(stream);
end:
return NULL;
DBG3("Adding consumer stream %d", stream->key);
pthread_mutex_lock(&consumer_data.lock);
+ pthread_mutex_lock(&stream->lock);
rcu_read_lock();
/* Steal stream identifier to avoid having streams with the same key */
consumer_data.need_update = 1;
rcu_read_unlock();
+ pthread_mutex_unlock(&stream->lock);
pthread_mutex_unlock(&consumer_data.lock);
return ret;
int ret;
struct lttng_ht_iter iter;
+ DBG("Consumer delete channel key %d", channel->key);
+
pthread_mutex_lock(&consumer_data.lock);
switch (consumer_data.type) {
DBG("Updating poll fd array");
rcu_read_lock();
cds_lfht_for_each_entry(ht->ht, &iter.iter, stream, node.node) {
- if (stream->state != LTTNG_CONSUMER_ACTIVE_STREAM) {
+ /*
+ * Only active streams with an active end point can be added to the
+ * poll set and local stream storage of the thread.
+ *
+ * There is a potential race here for endpoint_status to be updated
+ * just after the check. However, this is OK since the stream(s) will
+ * be deleted once the thread is notified that the end point state has
+ * changed where this function will be called back again.
+ */
+ if (stream->state != LTTNG_CONSUMER_ACTIVE_STREAM ||
+ stream->endpoint_status == CONSUMER_ENDPOINT_INACTIVE) {
continue;
}
DBG("Active FD %d", stream->wait_fd);
}
/*
- * Close all the tracefiles and stream fds, should be called when all instances
- * are destroyed.
+ * Close all the tracefiles and stream fds and MUST be called when all
+ * instances are destroyed i.e. when all threads were joined and are ended.
*/
void lttng_consumer_cleanup(void)
{
rcu_read_unlock();
lttng_ht_destroy(consumer_data.channel_ht);
+
+ cleanup_relayd_ht();
+
+ /*
+ * This HT contains streams that are freed by either the metadata thread or
+ * the data thread so we do *nothing* on the hash table and simply destroy
+ * it.
+ */
+ lttng_ht_destroy(consumer_data.stream_list_ht);
}
/*
* core function for writing trace buffers to either the local filesystem or
* the network.
*
+ * It must be called with the stream lock held.
+ *
* Careful review MUST be put if any changes occur!
*
* Returns the number of bytes written
/* Default is on the disk */
int outfd = stream->out_fd;
struct consumer_relayd_sock_pair *relayd = NULL;
+ unsigned int relayd_hang_up = 0;
/* RCU lock for the relayd pointer */
rcu_read_lock();
- pthread_mutex_lock(&stream->lock);
-
/* Flag that the current stream if set for network streaming. */
if (stream->net_seq_idx != -1) {
relayd = consumer_find_relayd(stream->net_seq_idx);
ret = write_relayd_metadata_id(outfd, stream, relayd, padding);
if (ret < 0) {
written = ret;
+ /* Socket operation failed. We consider the relayd dead */
+ if (ret == -EPIPE || ret == -EINVAL) {
+ relayd_hang_up = 1;
+ goto write_error;
+ }
goto end;
}
}
+ } else {
+ /* Socket operation failed. We consider the relayd dead */
+ if (ret == -EPIPE || ret == -EINVAL) {
+ relayd_hang_up = 1;
+ goto write_error;
+ }
+ /* Else, use the default set before which is the filesystem. */
}
- /* Else, use the default set before which is the filesystem. */
} else {
/* No streaming, we have to set the len with the full padding */
len += padding;
if (written == 0) {
written = ret;
}
+ /* Socket operation failed. We consider the relayd dead */
+ if (errno == EPIPE || errno == EINVAL) {
+ relayd_hang_up = 1;
+ goto write_error;
+ }
goto end;
} else if (ret > len) {
PERROR("Error in file write (ret %zd > len %lu)", ret, len);
}
lttng_consumer_sync_trace_file(stream, orig_offset);
+write_error:
+ /*
+ * This is a special case that the relayd has closed its socket. Let's
+ * cleanup the relayd object and all associated streams.
+ */
+ if (relayd && relayd_hang_up) {
+ cleanup_relayd(relayd, ctx);
+ }
+
end:
/* Unlock only if ctrl socket used */
if (relayd && stream->metadata_flag) {
pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
}
- pthread_mutex_unlock(&stream->lock);
rcu_read_unlock();
return written;
/*
* Splice the data from the ring buffer to the tracefile.
*
+ * It must be called with the stream lock held.
+ *
* Returns the number of bytes spliced.
*/
ssize_t lttng_consumer_on_read_subbuffer_splice(
int outfd = stream->out_fd;
struct consumer_relayd_sock_pair *relayd = NULL;
int *splice_pipe;
+ unsigned int relayd_hang_up = 0;
switch (consumer_data.type) {
case LTTNG_CONSUMER_KERNEL:
/* RCU lock for the relayd pointer */
rcu_read_lock();
- pthread_mutex_lock(&stream->lock);
-
/* Flag that the current stream if set for network streaming. */
if (stream->net_seq_idx != -1) {
relayd = consumer_find_relayd(stream->net_seq_idx);
padding);
if (ret < 0) {
written = ret;
+ /* Socket operation failed. We consider the relayd dead */
+ if (ret == -EBADF) {
+ WARN("Remote relayd disconnected. Stopping");
+ relayd_hang_up = 1;
+ goto write_error;
+ }
goto end;
}
/* Use the returned socket. */
outfd = ret;
} else {
- ERR("Remote relayd disconnected. Stopping");
+ /* Socket operation failed. We consider the relayd dead */
+ if (ret == -EBADF) {
+ WARN("Remote relayd disconnected. Stopping");
+ relayd_hang_up = 1;
+ goto write_error;
+ }
goto end;
}
} else {
if (written == 0) {
written = ret_splice;
}
+ /* Socket operation failed. We consider the relayd dead */
+ if (errno == EBADF || errno == EPIPE) {
+ WARN("Remote relayd disconnected. Stopping");
+ relayd_hang_up = 1;
+ goto write_error;
+ }
ret = errno;
goto splice_error;
} else if (ret_splice > len) {
goto end;
+write_error:
+ /*
+ * This is a special case that the relayd has closed its socket. Let's
+ * cleanup the relayd object and all associated streams.
+ */
+ if (relayd && relayd_hang_up) {
+ cleanup_relayd(relayd, ctx);
+ /* Skip splice error so the consumer does not fail */
+ goto end;
+ }
+
splice_error:
/* send the appropriate error description to sessiond */
switch (ret) {
- case EBADF:
- lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_SPLICE_EBADF);
- break;
case EINVAL:
lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_SPLICE_EINVAL);
break;
if (relayd && stream->metadata_flag) {
pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
}
- pthread_mutex_unlock(&stream->lock);
rcu_read_unlock();
return written;
*/
static void destroy_data_stream_ht(struct lttng_ht *ht)
{
- int ret;
struct lttng_ht_iter iter;
struct lttng_consumer_stream *stream;
rcu_read_lock();
cds_lfht_for_each_entry(ht->ht, &iter.iter, stream, node.node) {
- ret = lttng_ht_del(ht, &iter);
- assert(!ret);
-
- call_rcu(&stream->node.head, consumer_free_stream);
+ /*
+ * Ignore return value since we are currently cleaning up so any error
+ * can't be handled.
+ */
+ (void) consumer_del_stream(stream, ht);
}
rcu_read_unlock();
*/
static void destroy_stream_ht(struct lttng_ht *ht)
{
- int ret;
struct lttng_ht_iter iter;
struct lttng_consumer_stream *stream;
rcu_read_lock();
cds_lfht_for_each_entry(ht->ht, &iter.iter, stream, node.node) {
- ret = lttng_ht_del(ht, &iter);
- assert(!ret);
-
- call_rcu(&stream->node.head, consumer_free_stream);
+ /*
+ * Ignore return value since we are currently cleaning up so any error
+ * can't be handled.
+ */
+ (void) consumer_del_metadata_stream(stream, ht);
}
rcu_read_unlock();
}
pthread_mutex_lock(&consumer_data.lock);
+ pthread_mutex_lock(&stream->lock);
+
switch (consumer_data.type) {
case LTTNG_CONSUMER_KERNEL:
if (stream->mmap_base != NULL) {
}
end:
+ pthread_mutex_unlock(&stream->lock);
pthread_mutex_unlock(&consumer_data.lock);
if (free_chan) {
{
int ret = 0;
struct consumer_relayd_sock_pair *relayd;
+ struct lttng_ht_iter iter;
+ struct lttng_ht_node_ulong *node;
assert(stream);
assert(ht);
DBG3("Adding metadata stream %d to hash table", stream->wait_fd);
pthread_mutex_lock(&consumer_data.lock);
+ pthread_mutex_lock(&stream->lock);
/*
* From here, refcounts are updated so be _careful_ when returning an error
*/
rcu_read_lock();
+
+ /*
+ * Lookup the stream just to make sure it does not exist in our internal
+ * state. This should NEVER happen.
+ */
+ lttng_ht_lookup(ht, (void *)((unsigned long) stream->wait_fd), &iter);
+ node = lttng_ht_iter_get_node_ulong(&iter);
+ assert(!node);
+
/* Find relayd and, if one is found, increment refcount. */
relayd = consumer_find_relayd(stream->net_seq_idx);
if (relayd != NULL) {
uatomic_dec(&stream->chan->nb_init_streams);
}
- /* Steal stream identifier to avoid having streams with the same key */
- consumer_steal_stream_key(stream->key, ht);
-
lttng_ht_add_unique_ulong(ht, &stream->node);
/*
rcu_read_unlock();
+ pthread_mutex_unlock(&stream->lock);
pthread_mutex_unlock(&consumer_data.lock);
return ret;
}
+/*
+ * Delete data stream that are flagged for deletion (endpoint_status).
+ */
+static void validate_endpoint_status_data_stream(void)
+{
+ struct lttng_ht_iter iter;
+ struct lttng_consumer_stream *stream;
+
+ DBG("Consumer delete flagged data stream");
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry(data_ht->ht, &iter.iter, stream, node.node) {
+ /* Validate delete flag of the stream */
+ if (stream->endpoint_status == CONSUMER_ENDPOINT_ACTIVE) {
+ continue;
+ }
+ /* Delete it right now */
+ consumer_del_stream(stream, data_ht);
+ }
+ rcu_read_unlock();
+}
+
+/*
+ * Delete metadata stream that are flagged for deletion (endpoint_status).
+ */
+static void validate_endpoint_status_metadata_stream(
+ struct lttng_poll_event *pollset)
+{
+ struct lttng_ht_iter iter;
+ struct lttng_consumer_stream *stream;
+
+ DBG("Consumer delete flagged metadata stream");
+
+ assert(pollset);
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry(metadata_ht->ht, &iter.iter, stream, node.node) {
+ /* Validate delete flag of the stream */
+ if (stream->endpoint_status == CONSUMER_ENDPOINT_ACTIVE) {
+ continue;
+ }
+ /*
+ * Remove from pollset so the metadata thread can continue without
+ * blocking on a deleted stream.
+ */
+ lttng_poll_del(pollset, stream->wait_fd);
+
+ /* Delete it right now */
+ consumer_del_metadata_stream(stream, metadata_ht);
+ }
+ rcu_read_unlock();
+}
+
/*
* Thread polls on metadata file descriptor and write them on disk or on the
* network.
rcu_register_thread();
+ metadata_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
+ if (!metadata_ht) {
+ /* ENOMEM at this point. Better to bail out. */
+ goto error;
+ }
+
DBG("Thread metadata poll started");
/* Size is set to 1 for the consumer_metadata pipe */
* since their might be data to consume.
*/
lttng_poll_del(&events, ctx->consumer_metadata_pipe[0]);
- close(ctx->consumer_metadata_pipe[0]);
+ ret = close(ctx->consumer_metadata_pipe[0]);
+ if (ret < 0) {
+ PERROR("close metadata pipe");
+ }
continue;
} else if (revents & LPOLLIN) {
do {
continue;
}
+ /* A NULL stream means that the state has changed. */
+ if (stream == NULL) {
+ /* Check for deleted streams. */
+ validate_endpoint_status_metadata_stream(&events);
+ continue;
+ }
+
DBG("Adding metadata stream %d to poll set",
stream->wait_fd);
DBG("Metadata poll thread exiting");
lttng_poll_clean(&events);
- if (metadata_ht) {
- destroy_stream_ht(metadata_ht);
- }
+ destroy_stream_ht(metadata_ht);
rcu_unregister_thread();
return NULL;
data_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
if (data_ht == NULL) {
+ /* ENOMEM at this point. Better to bail out. */
goto end;
}
/* poll on the array of fds */
restart:
DBG("polling on %d fd", nb_fd + 1);
- num_rdy = poll(pollfd, nb_fd + 1, consumer_poll_timeout);
+ num_rdy = poll(pollfd, nb_fd + 1, -1);
DBG("poll num_rdy : %d", num_rdy);
if (num_rdy == -1) {
/*
* waking us up to test it.
*/
if (new_stream == NULL) {
+ validate_endpoint_status_data_stream();
continue;
}
/* Take care of high priority channels first. */
for (i = 0; i < nb_fd; i++) {
+ if (local_stream[i] == NULL) {
+ continue;
+ }
if (pollfd[i].revents & POLLPRI) {
DBG("Urgent read on fd %d", pollfd[i].fd);
high_prio = 1;
if (len < 0 && len != -EAGAIN && len != -ENODATA) {
/* Clean the stream and free it. */
consumer_del_stream(local_stream[i], data_ht);
+ local_stream[i] = NULL;
} else if (len > 0) {
local_stream[i]->data_read = 1;
}
/* Take care of low priority channels. */
for (i = 0; i < nb_fd; i++) {
+ if (local_stream[i] == NULL) {
+ continue;
+ }
if ((pollfd[i].revents & POLLIN) ||
local_stream[i]->hangup_flush_done) {
DBG("Normal read on fd %d", pollfd[i].fd);
if (len < 0 && len != -EAGAIN && len != -ENODATA) {
/* Clean the stream and free it. */
consumer_del_stream(local_stream[i], data_ht);
+ local_stream[i] = NULL;
} else if (len > 0) {
local_stream[i]->data_read = 1;
}
/* Handle hangup and errors */
for (i = 0; i < nb_fd; i++) {
+ if (local_stream[i] == NULL) {
+ continue;
+ }
if (!local_stream[i]->hangup_flush_done
&& (pollfd[i].revents & (POLLHUP | POLLERR | POLLNVAL))
&& (consumer_data.type == LTTNG_CONSUMER32_UST
|| consumer_data.type == LTTNG_CONSUMER64_UST)) {
DBG("fd %d is hup|err|nval. Attempting flush and read.",
- pollfd[i].fd);
+ pollfd[i].fd);
lttng_ustconsumer_on_stream_hangup(local_stream[i]);
/* Attempt read again, for the data we just flushed. */
local_stream[i]->data_read = 1;
DBG("Polling fd %d tells it has hung up.", pollfd[i].fd);
if (!local_stream[i]->data_read) {
consumer_del_stream(local_stream[i], data_ht);
+ local_stream[i] = NULL;
num_hup++;
}
} else if (pollfd[i].revents & POLLERR) {
ERR("Error returned in polling fd %d.", pollfd[i].fd);
if (!local_stream[i]->data_read) {
consumer_del_stream(local_stream[i], data_ht);
+ local_stream[i] = NULL;
num_hup++;
}
} else if (pollfd[i].revents & POLLNVAL) {
ERR("Polling fd %d tells fd is not open.", pollfd[i].fd);
if (!local_stream[i]->data_read) {
consumer_del_stream(local_stream[i], data_ht);
+ local_stream[i] = NULL;
num_hup++;
}
}
- local_stream[i]->data_read = 0;
+ if (local_stream[i] != NULL) {
+ local_stream[i]->data_read = 0;
+ }
}
}
end:
* only tracked fd in the poll set. The thread will take care of closing
* the read side.
*/
- close(ctx->consumer_metadata_pipe[1]);
-
- if (data_ht) {
- destroy_data_stream_ht(data_ht);
+ ret = close(ctx->consumer_metadata_pipe[1]);
+ if (ret < 0) {
+ PERROR("close data pipe");
}
+ destroy_data_stream_ht(data_ht);
+
rcu_unregister_thread();
return NULL;
}
*/
void *consumer_thread_sessiond_poll(void *data)
{
- int sock, client_socket, ret;
+ int sock = -1, client_socket, ret;
/*
* structure to poll for incoming data on communication socket avoids
* making blocking sockets.
goto end;
}
+ /* This socket is not useful anymore. */
+ ret = close(client_socket);
+ if (ret < 0) {
+ PERROR("close client_socket");
+ }
+ client_socket = -1;
+
/* update the polling structure to poll on the established socket */
consumer_sockpoll[1].fd = sock;
consumer_sockpoll[1].events = POLLIN | POLLPRI;
*/
consumer_quit = 1;
- /*
- * 2s of grace period, if no polling events occur during
- * this period, the polling thread will exit even if there
- * are still open FDs (should not happen, but safety mechanism).
- */
- consumer_poll_timeout = LTTNG_CONSUMER_POLL_TIMEOUT;
-
/*
* Notify the data poll thread to poll back again and test the
- * consumer_quit state to quit gracefully.
+ * consumer_quit state that we just set so to quit gracefully.
*/
- do {
- struct lttng_consumer_stream *null_stream = NULL;
+ notify_thread_pipe(ctx->consumer_data_pipe[1]);
- ret = write(ctx->consumer_data_pipe[1], &null_stream,
- sizeof(null_stream));
- } while (ret < 0 && errno == EINTR);
+ /* Cleaning up possibly open sockets. */
+ if (sock >= 0) {
+ ret = close(sock);
+ if (ret < 0) {
+ PERROR("close sock sessiond poll");
+ }
+ }
+ if (client_socket >= 0) {
+ ret = close(sock);
+ if (ret < 0) {
+ PERROR("close client_socket sessiond poll");
+ }
+ }
rcu_unregister_thread();
return NULL;
ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
struct lttng_consumer_local_data *ctx)
{
+ ssize_t ret;
+
+ pthread_mutex_lock(&stream->lock);
+
switch (consumer_data.type) {
case LTTNG_CONSUMER_KERNEL:
- return lttng_kconsumer_read_subbuffer(stream, ctx);
+ ret = lttng_kconsumer_read_subbuffer(stream, ctx);
+ break;
case LTTNG_CONSUMER32_UST:
case LTTNG_CONSUMER64_UST:
- return lttng_ustconsumer_read_subbuffer(stream, ctx);
+ ret = lttng_ustconsumer_read_subbuffer(stream, ctx);
+ break;
default:
ERR("Unknown consumer_data type");
assert(0);
- return -ENOSYS;
+ ret = -ENOSYS;
+ break;
}
+
+ pthread_mutex_unlock(&stream->lock);
+ return ret;
}
int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream)
consumer_data.channel_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
consumer_data.relayd_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
consumer_data.stream_list_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
-
- metadata_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
- assert(metadata_ht);
- data_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
- assert(data_ht);
}
/*
struct lttng_consumer_local_data *ctx, int sock,
struct pollfd *consumer_sockpoll, struct lttcomm_sock *relayd_sock)
{
- int fd, ret = -1;
+ int fd = -1, ret = -1;
struct consumer_relayd_sock_pair *relayd;
DBG("Consumer adding relayd socket (idx: %d)", net_seq_idx);
if (ret != sizeof(fd)) {
lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD);
ret = -1;
+ fd = -1; /* Just in case it gets set with an invalid value. */
goto error;
}
/* Copy received lttcomm socket */
lttcomm_copy_sock(&relayd->control_sock, relayd_sock);
ret = lttcomm_create_sock(&relayd->control_sock);
+ /* Immediately try to close the created socket if valid. */
+ if (relayd->control_sock.fd >= 0) {
+ if (close(relayd->control_sock.fd)) {
+ PERROR("close relayd control socket");
+ }
+ }
+ /* Handle create_sock error. */
if (ret < 0) {
goto error;
}
- /* Close the created socket fd which is useless */
- close(relayd->control_sock.fd);
-
/* Assign new file descriptor */
relayd->control_sock.fd = fd;
break;
/* Copy received lttcomm socket */
lttcomm_copy_sock(&relayd->data_sock, relayd_sock);
ret = lttcomm_create_sock(&relayd->data_sock);
+ /* Immediately try to close the created socket if valid. */
+ if (relayd->data_sock.fd >= 0) {
+ if (close(relayd->data_sock.fd)) {
+ PERROR("close relayd data socket");
+ }
+ }
+ /* Handle create_sock error. */
if (ret < 0) {
goto error;
}
- /* Close the created socket fd which is useless */
- close(relayd->data_sock.fd);
-
/* Assign new file descriptor */
relayd->data_sock.fd = fd;
break;
add_relayd(relayd);
/* All good! */
- ret = 0;
+ return 0;
error:
+ /* Close received socket if valid. */
+ if (fd >= 0) {
+ if (close(fd)) {
+ PERROR("close received socket");
+ }
+ }
+ return ret;
+}
+
+/*
+ * 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;
}
* Check if for a given session id there is still data needed to be extract
* from the buffers.
*
- * Return 1 if data is in fact available to be read or else 0.
+ * Return 1 if data is pending or else 0 meaning ready to be read.
*/
-int consumer_data_available(uint64_t id)
+int consumer_data_pending(uint64_t id)
{
int ret;
struct lttng_ht_iter iter;
struct lttng_ht *ht;
struct lttng_consumer_stream *stream;
struct consumer_relayd_sock_pair *relayd;
- int (*data_available)(struct lttng_consumer_stream *);
+ int (*data_pending)(struct lttng_consumer_stream *);
- DBG("Consumer data available command on session id %" PRIu64, id);
+ DBG("Consumer data pending command on session id %" PRIu64, id);
rcu_read_lock();
pthread_mutex_lock(&consumer_data.lock);
switch (consumer_data.type) {
case LTTNG_CONSUMER_KERNEL:
- data_available = lttng_kconsumer_data_available;
+ data_pending = lttng_kconsumer_data_pending;
break;
case LTTNG_CONSUMER32_UST:
case LTTNG_CONSUMER64_UST:
- data_available = lttng_ustconsumer_data_available;
+ data_pending = lttng_ustconsumer_data_pending;
break;
default:
ERR("Unknown consumer data type");
ht = consumer_data.stream_list_ht;
cds_lfht_for_each_entry_duplicate(ht->ht,
- ht->hash_fct((void *)((unsigned long) id), 0x42UL),
+ ht->hash_fct((void *)((unsigned long) id), lttng_ht_seed),
ht->match_fct, (void *)((unsigned long) id),
&iter.iter, stream, node_session_id.node) {
- /* Check the stream for data. */
- ret = data_available(stream);
- if (ret == 0) {
- goto data_not_available;
+ /* If this call fails, the stream is being used hence data pending. */
+ ret = stream_try_lock(stream);
+ if (!ret) {
+ goto data_not_pending;
+ }
+
+ /*
+ * A removed node from the hash table indicates that the stream has
+ * been deleted thus having a guarantee that the buffers are closed
+ * on the consumer side. However, data can still be transmitted
+ * over the network so don't skip the relayd check.
+ */
+ ret = cds_lfht_is_node_deleted(&stream->node.node);
+ if (!ret) {
+ /* Check the stream if there is data in the buffers. */
+ ret = data_pending(stream);
+ if (ret == 1) {
+ pthread_mutex_unlock(&stream->lock);
+ goto data_not_pending;
+ }
}
+ /* Relayd check */
if (stream->net_seq_idx != -1) {
relayd = consumer_find_relayd(stream->net_seq_idx);
- assert(relayd);
+ if (!relayd) {
+ /*
+ * At this point, if the relayd object is not available for the
+ * given stream, it is because the relayd is being cleaned up
+ * so every stream associated with it (for a session id value)
+ * are or will be marked for deletion hence no data pending.
+ */
+ pthread_mutex_unlock(&stream->lock);
+ goto data_not_pending;
+ }
- pthread_mutex_lock(&stream->lock);
pthread_mutex_lock(&relayd->ctrl_sock_mutex);
if (stream->metadata_flag) {
ret = relayd_quiescent_control(&relayd->control_sock);
} else {
- ret = relayd_data_available(&relayd->control_sock,
+ ret = relayd_data_pending(&relayd->control_sock,
stream->relayd_stream_id, stream->next_net_seq_num);
}
pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
- pthread_mutex_unlock(&stream->lock);
- if (ret == 0) {
- goto data_not_available;
+ if (ret == 1) {
+ pthread_mutex_unlock(&stream->lock);
+ goto data_not_pending;
}
}
+ pthread_mutex_unlock(&stream->lock);
}
/*
/* Data is available to be read by a viewer. */
pthread_mutex_unlock(&consumer_data.lock);
rcu_read_unlock();
- return 1;
+ return 0;
-data_not_available:
+data_not_pending:
/* Data is still being extracted from buffers. */
pthread_mutex_unlock(&consumer_data.lock);
rcu_read_unlock();
- return 0;
+ return 1;
}
projects / lttng-tools.git / blobdiff