#include <common/sessiond-comm/sessiond-comm.h>
#include <common/relayd/relayd.h>
#include <common/compat/fcntl.h>
+#include <common/compat/endian.h>
#include <common/consumer-metadata-cache.h>
#include <common/consumer-stream.h>
#include <common/consumer-timer.h>
/* Keep stream reference when creating metadata. */
if (channel->type == CONSUMER_CHANNEL_TYPE_METADATA) {
channel->metadata_stream = stream;
- stream->ust_metadata_poll_pipe[0] = ust_metadata_pipe[0];
- stream->ust_metadata_poll_pipe[1] = ust_metadata_pipe[1];
+ if (channel->monitor) {
+ /* Set metadata poll pipe if we created one */
+ memcpy(stream->ust_metadata_poll_pipe,
+ ust_metadata_pipe,
+ sizeof(ust_metadata_pipe));
+ }
}
}
* the stream is still in the local stream list of the channel. This call
* will make sure to clean that list.
*/
- cds_list_del(&metadata->metadata_stream->send_node);
consumer_stream_destroy(metadata->metadata_stream, NULL);
+ cds_list_del(&metadata->metadata_stream->send_node);
+ metadata->metadata_stream = NULL;
error_no_stream:
end:
return ret;
* Clean up the stream completly because the next snapshot will use a new
* metadata stream.
*/
- cds_list_del(&metadata_stream->send_node);
consumer_stream_destroy(metadata_stream, NULL);
+ cds_list_del(&metadata_stream->send_node);
metadata_channel->metadata_stream = NULL;
error:
* Returns 0 on success, < 0 on error
*/
static int snapshot_channel(uint64_t key, char *path, uint64_t relayd_id,
- uint64_t max_stream_size, struct lttng_consumer_local_data *ctx)
+ uint64_t nb_packets_per_stream, struct lttng_consumer_local_data *ctx)
{
int ret;
unsigned use_relayd = 0;
/*
* The original value is sent back if max stream size is larger than
- * the possible size of the snapshot. Also, we asume that the session
+ * the possible size of the snapshot. Also, we assume that the session
* daemon should never send a maximum stream size that is lower than
* subbuffer size.
*/
- consumed_pos = consumer_get_consumed_maxsize(consumed_pos,
- produced_pos, max_stream_size);
+ consumed_pos = consumer_get_consume_start_pos(consumed_pos,
+ produced_pos, nb_packets_per_stream,
+ stream->max_sb_size);
while (consumed_pos < produced_pos) {
ssize_t read_len;
}
/*
- * Receive the metadata updates from the sessiond.
+ * Receive the metadata updates from the sessiond. Supports receiving
+ * overlapping metadata, but is needs to always belong to a contiguous
+ * range starting from 0.
+ * Be careful about the locks held when calling this function: it needs
+ * the metadata cache flush to concurrently progress in order to
+ * complete.
*/
int lttng_ustconsumer_recv_metadata(int sock, uint64_t key, uint64_t offset,
uint64_t len, struct lttng_consumer_channel *channel,
health_code_update();
- if (msg.cmd_type == LTTNG_CONSUMER_STOP) {
- /*
- * Notify the session daemon that the command is completed.
- *
- * On transport layer error, the function call will print an error
- * message so handling the returned code is a bit useless since we
- * return an error code anyway.
- */
- (void) consumer_send_status_msg(sock, ret_code);
- return -ENOENT;
- }
+ /* deprecated */
+ assert(msg.cmd_type != LTTNG_CONSUMER_STOP);
health_code_update();
relayd = consumer_find_relayd(index);
if (relayd == NULL) {
DBG("Unable to find relayd %" PRIu64, index);
- ret_code = LTTNG_ERR_NO_CONSUMER;
+ ret_code = LTTCOMM_CONSUMERD_RELAYD_FAIL;
}
/*
channel = consumer_find_channel(key);
if (!channel) {
ERR("UST consumer get channel key %" PRIu64 " not found", key);
- ret_code = LTTNG_ERR_UST_CHAN_NOT_FOUND;
+ ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
goto end_msg_sessiond;
}
health_code_update();
+ if (!len) {
+ /*
+ * There is nothing to receive. We have simply
+ * checked whether the channel can be found.
+ */
+ ret_code = LTTCOMM_CONSUMERD_SUCCESS;
+ goto end_msg_sessiond;
+ }
+
/* Tell session daemon we are ready to receive the metadata. */
ret = consumer_send_status_msg(sock, LTTCOMM_CONSUMERD_SUCCESS);
if (ret < 0) {
health_poll_entry();
ret = lttng_consumer_poll_socket(consumer_sockpoll);
health_poll_exit();
- if (ret < 0) {
+ if (ret) {
goto error_fatal;
}
ctx);
if (ret < 0) {
ERR("Snapshot metadata failed");
- ret_code = LTTNG_ERR_UST_META_FAIL;
+ ret_code = LTTCOMM_CONSUMERD_ERROR_METADATA;
}
} else {
ret = snapshot_channel(msg.u.snapshot_channel.key,
msg.u.snapshot_channel.pathname,
msg.u.snapshot_channel.relayd_id,
- msg.u.snapshot_channel.max_stream_size,
+ msg.u.snapshot_channel.nb_packets_per_stream,
ctx);
if (ret < 0) {
ERR("Snapshot channel failed");
- ret_code = LTTNG_ERR_UST_CHAN_FAIL;
+ ret_code = LTTCOMM_CONSUMERD_CHANNEL_FAIL;
}
}
int ret;
pthread_mutex_lock(&stream->chan->metadata_cache->lock);
- if (stream->chan->metadata_cache->contiguous
+ if (stream->chan->metadata_cache->max_offset
== stream->ust_metadata_pushed) {
ret = 0;
goto end;
write_len = ustctl_write_one_packet_to_channel(stream->chan->uchan,
&stream->chan->metadata_cache->data[stream->ust_metadata_pushed],
- stream->chan->metadata_cache->contiguous
+ stream->chan->metadata_cache->max_offset
- stream->ust_metadata_pushed);
assert(write_len != 0);
if (write_len < 0) {
}
stream->ust_metadata_pushed += write_len;
- assert(stream->chan->metadata_cache->contiguous >=
+ assert(stream->chan->metadata_cache->max_offset >=
stream->ust_metadata_pushed);
ret = write_len;
* Sync metadata meaning request them to the session daemon and snapshot to the
* metadata thread can consumer them.
*
- * Metadata stream lock MUST be acquired.
+ * Metadata stream lock is held here, but we need to release it when
+ * interacting with sessiond, else we cause a deadlock with live
+ * awaiting on metadata to be pushed out.
*
* Return 0 if new metadatda is available, EAGAIN if the metadata stream
* is empty or a negative value on error.
assert(ctx);
assert(metadata);
+ pthread_mutex_unlock(&metadata->lock);
/*
* Request metadata from the sessiond, but don't wait for the flush
* because we locked the metadata thread.
if (ret < 0) {
goto end;
}
+ pthread_mutex_lock(&metadata->lock);
ret = commit_one_metadata_packet(metadata);
if (ret <= 0) {
return ret;
}
+/*
+ * Return 0 on success else a negative value.
+ */
+static int notify_if_more_data(struct lttng_consumer_stream *stream,
+ struct lttng_consumer_local_data *ctx)
+{
+ int ret;
+ struct ustctl_consumer_stream *ustream;
+
+ assert(stream);
+ assert(ctx);
+
+ ustream = stream->ustream;
+
+ /*
+ * First, we are going to check if there is a new subbuffer available
+ * before reading the stream wait_fd.
+ */
+ /* Get the next subbuffer */
+ ret = ustctl_get_next_subbuf(ustream);
+ if (ret) {
+ /* No more data found, flag the stream. */
+ stream->has_data = 0;
+ ret = 0;
+ goto end;
+ }
+
+ ret = ustctl_put_subbuf(ustream);
+ assert(!ret);
+
+ /* This stream still has data. Flag it and wake up the data thread. */
+ stream->has_data = 1;
+
+ if (stream->monitor && !stream->hangup_flush_done && !ctx->has_wakeup) {
+ ssize_t writelen;
+
+ writelen = lttng_pipe_write(ctx->consumer_wakeup_pipe, "!", 1);
+ if (writelen < 0 && errno != EAGAIN && errno != EWOULDBLOCK) {
+ ret = writelen;
+ goto end;
+ }
+
+ /* The wake up pipe has been notified. */
+ ctx->has_wakeup = 1;
+ }
+ ret = 0;
+
+end:
+ return ret;
+}
+
/*
* Read subbuffer from the given stream.
*
unsigned long len, subbuf_size, padding;
int err, write_index = 1;
long ret = 0;
- char dummy;
struct ustctl_consumer_stream *ustream;
struct ctf_packet_index index;
ustream = stream->ustream;
/*
- * We can consume the 1 byte written into the wait_fd by UST.
- * Don't trigger error if we cannot read this one byte (read
- * returns 0), or if the error is EAGAIN or EWOULDBLOCK.
+ * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
+ * error if we cannot read this one byte (read returns 0), or if the error
+ * is EAGAIN or EWOULDBLOCK.
+ *
+ * This is only done when the stream is monitored by a thread, before the
+ * flush is done after a hangup and if the stream is not flagged with data
+ * since there might be nothing to consume in the wait fd but still have
+ * data available flagged by the consumer wake up pipe.
*/
- if (stream->monitor && !stream->hangup_flush_done) {
+ if (stream->monitor && !stream->hangup_flush_done && !stream->has_data) {
+ char dummy;
ssize_t readlen;
readlen = lttng_read(stream->wait_fd, &dummy, 1);
err = ustctl_put_next_subbuf(ustream);
assert(err == 0);
+ /*
+ * This will consumer the byte on the wait_fd if and only if there is not
+ * next subbuffer to be acquired.
+ */
+ if (!stream->metadata_flag) {
+ ret = notify_if_more_data(stream, ctx);
+ if (ret < 0) {
+ goto end;
+ }
+ }
+
/* Write index if needed. */
if (!write_index) {
goto end;
/*
* In live, block until all the metadata is sent.
*/
+ pthread_mutex_lock(&stream->metadata_timer_lock);
+ assert(!stream->missed_metadata_flush);
+ stream->waiting_on_metadata = true;
+ pthread_mutex_unlock(&stream->metadata_timer_lock);
+
err = consumer_stream_sync_metadata(ctx, stream->session_id);
+
+ pthread_mutex_lock(&stream->metadata_timer_lock);
+ stream->waiting_on_metadata = false;
+ if (stream->missed_metadata_flush) {
+ stream->missed_metadata_flush = false;
+ pthread_mutex_unlock(&stream->metadata_timer_lock);
+ (void) consumer_flush_ust_index(stream);
+ } else {
+ pthread_mutex_unlock(&stream->metadata_timer_lock);
+ }
+
if (err < 0) {
goto end;
}
uint64_t contiguous, pushed;
/* Ease our life a bit. */
- contiguous = stream->chan->metadata_cache->contiguous;
+ contiguous = stream->chan->metadata_cache->max_offset;
pushed = stream->ust_metadata_pushed;
/*
*/
DBG("UST consumer metadata pending check: contiguous %" PRIu64 " vs pushed %" PRIu64,
contiguous, pushed);
- assert(((int64_t) contiguous - pushed) >= 0);
+ assert(((int64_t) (contiguous - pushed)) >= 0);
if ((contiguous != pushed) ||
(((int64_t) contiguous - pushed) > 0 || contiguous == 0)) {
ret = 1; /* Data is pending */
* function or any of its callees. Timers have a very strict locking
* semantic with respect to teardown. Failure to respect this semantic
* introduces deadlocks.
+ *
+ * DON'T hold the metadata lock when calling this function, else this
+ * can cause deadlock involving consumer awaiting for metadata to be
+ * pushed out due to concurrent interaction with the session daemon.
*/
int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data *ctx,
struct lttng_consumer_channel *channel, int timer, int wait)
assert(channel);
assert(channel->metadata_cache);
+ memset(&request, 0, sizeof(request));
+
/* send the metadata request to sessiond */
switch (consumer_data.type) {
case LTTNG_CONSUMER64_UST:
pthread_mutex_unlock(&ctx->metadata_socket_lock);
return ret;
}
+
+/*
+ * Return the ustctl call for the get stream id.
+ */
+int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream *stream,
+ uint64_t *stream_id)
+{
+ assert(stream);
+ assert(stream_id);
+
+ return ustctl_get_stream_id(stream->ustream, stream_id);
+}