/*
- * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
- * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * 2012 - David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
+ * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
*
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
+#include "common/index/ctf-index.h"
#define _LGPL_SOURCE
#include <assert.h>
#include <poll.h>
static struct lttng_ht *metadata_ht;
static struct lttng_ht *data_ht;
+static const char *get_consumer_domain(void)
+{
+ switch (consumer_data.type) {
+ case LTTNG_CONSUMER_KERNEL:
+ return DEFAULT_KERNEL_TRACE_DIR;
+ case LTTNG_CONSUMER64_UST:
+ /* Fall-through. */
+ case LTTNG_CONSUMER32_UST:
+ return DEFAULT_UST_TRACE_DIR;
+ default:
+ abort();
+ }
+}
+
/*
* Notify a thread lttng 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
channel->tracefile_size;
}
-struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
- uint64_t stream_key,
- const char *channel_name,
- uint64_t relayd_id,
- uint64_t session_id,
- struct lttng_trace_chunk *trace_chunk,
- int cpu,
- int *alloc_ret,
- enum consumer_channel_type type,
- unsigned int monitor)
-{
- int ret;
- struct lttng_consumer_stream *stream;
-
- stream = zmalloc(sizeof(*stream));
- if (stream == NULL) {
- PERROR("malloc struct lttng_consumer_stream");
- ret = -ENOMEM;
- goto end;
- }
-
- if (trace_chunk && !lttng_trace_chunk_get(trace_chunk)) {
- ERR("Failed to acquire trace chunk reference during the creation of a stream");
- ret = -1;
- goto error;
- }
-
- rcu_read_lock();
- stream->key = stream_key;
- stream->trace_chunk = trace_chunk;
- stream->out_fd = -1;
- stream->out_fd_offset = 0;
- stream->output_written = 0;
- stream->net_seq_idx = relayd_id;
- stream->session_id = session_id;
- stream->monitor = monitor;
- stream->endpoint_status = CONSUMER_ENDPOINT_ACTIVE;
- stream->index_file = NULL;
- stream->last_sequence_number = -1ULL;
- stream->rotate_position = -1ULL;
- pthread_mutex_init(&stream->lock, NULL);
- pthread_mutex_init(&stream->metadata_timer_lock, NULL);
-
- /* If channel is the metadata, flag this stream as metadata. */
- if (type == CONSUMER_CHANNEL_TYPE_METADATA) {
- stream->metadata_flag = 1;
- /* Metadata is flat out. */
- strncpy(stream->name, DEFAULT_METADATA_NAME, sizeof(stream->name));
- /* Live rendez-vous point. */
- pthread_cond_init(&stream->metadata_rdv, NULL);
- pthread_mutex_init(&stream->metadata_rdv_lock, NULL);
- } else {
- /* Format stream name to <channel_name>_<cpu_number> */
- ret = snprintf(stream->name, sizeof(stream->name), "%s_%d",
- channel_name, cpu);
- if (ret < 0) {
- PERROR("snprintf stream name");
- goto error;
- }
- }
-
- /* Key is always the wait_fd for streams. */
- lttng_ht_node_init_u64(&stream->node, stream->key);
-
- /* Init node per channel id key */
- lttng_ht_node_init_u64(&stream->node_channel_id, channel_key);
-
- /* Init session id node with the stream session id */
- lttng_ht_node_init_u64(&stream->node_session_id, stream->session_id);
-
- DBG3("Allocated stream %s (key %" PRIu64 ", chan_key %" PRIu64
- " relayd_id %" PRIu64 ", session_id %" PRIu64,
- stream->name, stream->key, channel_key,
- stream->net_seq_idx, stream->session_id);
-
- rcu_read_unlock();
- return stream;
-
-error:
- rcu_read_unlock();
- lttng_trace_chunk_put(stream->trace_chunk);
- free(stream);
-end:
- if (alloc_ret) {
- *alloc_ret = ret;
- }
- return NULL;
-}
-
/*
* Add a stream to the global list protected by a mutex.
*/
/* Add stream on the relayd */
pthread_mutex_lock(&relayd->ctrl_sock_mutex);
ret = relayd_add_stream(&relayd->control_sock, stream->name,
- path, &stream->relayd_stream_id,
+ get_consumer_domain(), path, &stream->relayd_stream_id,
stream->chan->tracefile_size,
stream->chan->tracefile_count,
stream->trace_chunk);
uint64_t session_id_per_pid,
unsigned int monitor,
unsigned int live_timer_interval,
+ bool is_in_live_session,
const char *root_shm_path,
const char *shm_path)
{
channel->tracefile_count = tracefile_count;
channel->monitor = monitor;
channel->live_timer_interval = live_timer_interval;
+ channel->is_live = is_in_live_session;
pthread_mutex_init(&channel->lock, NULL);
pthread_mutex_init(&channel->timer_lock, NULL);
struct lttng_consumer_local_data *lttng_consumer_create(
enum lttng_consumer_type type,
ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
- struct lttng_consumer_local_data *ctx),
+ struct lttng_consumer_local_data *ctx, bool locked_by_caller),
int (*recv_channel)(struct lttng_consumer_channel *channel),
int (*recv_stream)(struct lttng_consumer_stream *stream),
int (*update_stream)(uint64_t stream_key, uint32_t state))
* Returns the number of bytes written
*/
ssize_t lttng_consumer_on_read_subbuffer_mmap(
- struct lttng_consumer_local_data *ctx,
- struct lttng_consumer_stream *stream, unsigned long len,
- unsigned long padding,
- struct ctf_packet_index *index)
+ struct lttng_consumer_stream *stream,
+ const struct lttng_buffer_view *buffer,
+ unsigned long padding)
{
- unsigned long mmap_offset;
- void *mmap_base;
ssize_t ret = 0;
off_t orig_offset = stream->out_fd_offset;
/* Default is on the disk */
int outfd = stream->out_fd;
struct consumer_relayd_sock_pair *relayd = NULL;
unsigned int relayd_hang_up = 0;
+ const size_t subbuf_content_size = buffer->size - padding;
+ size_t write_len;
/* RCU lock for the relayd pointer */
rcu_read_lock();
}
}
- /* get the offset inside the fd to mmap */
- switch (consumer_data.type) {
- case LTTNG_CONSUMER_KERNEL:
- mmap_base = stream->mmap_base;
- ret = kernctl_get_mmap_read_offset(stream->wait_fd, &mmap_offset);
- if (ret < 0) {
- PERROR("tracer ctl get_mmap_read_offset");
- goto end;
- }
- break;
- case LTTNG_CONSUMER32_UST:
- case LTTNG_CONSUMER64_UST:
- mmap_base = lttng_ustctl_get_mmap_base(stream);
- if (!mmap_base) {
- ERR("read mmap get mmap base for stream %s", stream->name);
- ret = -EPERM;
- goto end;
- }
- ret = lttng_ustctl_get_mmap_read_offset(stream, &mmap_offset);
- if (ret != 0) {
- PERROR("tracer ctl get_mmap_read_offset");
- ret = -EINVAL;
- goto end;
- }
- break;
- default:
- ERR("Unknown consumer_data type");
- assert(0);
- }
-
/* Handle stream on the relayd if the output is on the network */
if (relayd) {
- unsigned long netlen = len;
+ unsigned long netlen = subbuf_content_size;
/*
* Lock the control socket for the complete duration of the function
goto write_error;
}
}
- } else {
- /* No streaming, we have to set the len with the full padding */
- len += padding;
+ write_len = subbuf_content_size;
+ } else {
+ /* No streaming; we have to write the full padding. */
if (stream->metadata_flag && stream->reset_metadata_flag) {
ret = utils_truncate_stream_file(stream->out_fd, 0);
if (ret < 0) {
* Check if we need to change the tracefile before writing the packet.
*/
if (stream->chan->tracefile_size > 0 &&
- (stream->tracefile_size_current + len) >
+ (stream->tracefile_size_current + buffer->size) >
stream->chan->tracefile_size) {
ret = consumer_stream_rotate_output_files(stream);
if (ret) {
outfd = stream->out_fd;
orig_offset = 0;
}
- stream->tracefile_size_current += len;
- if (index) {
- index->offset = htobe64(stream->out_fd_offset);
- }
+ stream->tracefile_size_current += buffer->size;
+ write_len = buffer->size;
}
/*
* This call guarantee that len or less is returned. It's impossible to
* receive a ret value that is bigger than len.
*/
- ret = lttng_write(outfd, mmap_base + mmap_offset, len);
- DBG("Consumer mmap write() ret %zd (len %lu)", ret, len);
- if (ret < 0 || ((size_t) ret != len)) {
+ ret = lttng_write(outfd, buffer->data, write_len);
+ DBG("Consumer mmap write() ret %zd (len %zu)", ret, write_len);
+ if (ret < 0 || ((size_t) ret != write_len)) {
/*
* Report error to caller if nothing was written else at least send the
* amount written.
DBG("Consumer mmap write detected relayd hang up");
} else {
/* Unhandled error, print it and stop function right now. */
- PERROR("Error in write mmap (ret %zd != len %lu)", ret, len);
+ PERROR("Error in write mmap (ret %zd != write_len %zu)", ret,
+ write_len);
}
goto write_error;
}
/* This call is useless on a socket so better save a syscall. */
if (!relayd) {
/* This won't block, but will start writeout asynchronously */
- lttng_sync_file_range(outfd, stream->out_fd_offset, len,
+ lttng_sync_file_range(outfd, stream->out_fd_offset, write_len,
SYNC_FILE_RANGE_WRITE);
- stream->out_fd_offset += len;
+ stream->out_fd_offset += write_len;
lttng_consumer_sync_trace_file(stream, orig_offset);
}
ssize_t lttng_consumer_on_read_subbuffer_splice(
struct lttng_consumer_local_data *ctx,
struct lttng_consumer_stream *stream, unsigned long len,
- unsigned long padding,
- struct ctf_packet_index *index)
+ unsigned long padding)
{
ssize_t ret = 0, written = 0, ret_splice = 0;
loff_t offset = 0;
orig_offset = 0;
}
stream->tracefile_size_current += len;
- index->offset = htobe64(stream->out_fd_offset);
}
while (len > 0) {
do {
health_code_update();
- len = ctx->on_buffer_ready(stream, ctx);
+ len = ctx->on_buffer_ready(stream, ctx, false);
/*
* We don't check the return value here since if we get
* a negative len, it means an error occurred thus we
do {
health_code_update();
- len = ctx->on_buffer_ready(stream, ctx);
+ len = ctx->on_buffer_ready(stream, ctx, false);
/*
* We don't check the return value here since if we get
* a negative len, it means an error occurred thus we
if (pollfd[i].revents & POLLPRI) {
DBG("Urgent read on fd %d", pollfd[i].fd);
high_prio = 1;
- len = ctx->on_buffer_ready(local_stream[i], ctx);
+ len = ctx->on_buffer_ready(local_stream[i], ctx, false);
/* it's ok to have an unavailable sub-buffer */
if (len < 0 && len != -EAGAIN && len != -ENODATA) {
/* Clean the stream and free it. */
local_stream[i]->hangup_flush_done ||
local_stream[i]->has_data) {
DBG("Normal read on fd %d", pollfd[i].fd);
- len = ctx->on_buffer_ready(local_stream[i], ctx);
+ len = ctx->on_buffer_ready(local_stream[i], ctx, false);
/* it's ok to have an unavailable sub-buffer */
if (len < 0 && len != -EAGAIN && len != -ENODATA) {
/* Clean the stream and free it. */
err = 0; /* All is OK */
goto end;
}
- DBG("received command on sock");
+ DBG("Received command on sock");
}
/* All is OK */
err = 0;
return NULL;
}
-ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
+static int post_consume(struct lttng_consumer_stream *stream,
+ const struct stream_subbuffer *subbuffer,
struct lttng_consumer_local_data *ctx)
{
- ssize_t ret;
+ size_t i;
+ int ret = 0;
+ const size_t count = lttng_dynamic_array_get_count(
+ &stream->read_subbuffer_ops.post_consume_cbs);
- pthread_mutex_lock(&stream->chan->lock);
- pthread_mutex_lock(&stream->lock);
- if (stream->metadata_flag) {
- pthread_mutex_lock(&stream->metadata_rdv_lock);
+ for (i = 0; i < count; i++) {
+ const post_consume_cb op = *(post_consume_cb *) lttng_dynamic_array_get_element(
+ &stream->read_subbuffer_ops.post_consume_cbs,
+ i);
+
+ ret = op(stream, subbuffer, ctx);
+ if (ret) {
+ goto end;
+ }
}
+end:
+ return ret;
+}
- switch (consumer_data.type) {
- case LTTNG_CONSUMER_KERNEL:
- ret = lttng_kconsumer_read_subbuffer(stream, ctx);
- break;
- case LTTNG_CONSUMER32_UST:
- case LTTNG_CONSUMER64_UST:
- ret = lttng_ustconsumer_read_subbuffer(stream, ctx);
- break;
- default:
- ERR("Unknown consumer_data type");
- assert(0);
- ret = -ENOSYS;
- break;
+ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
+ struct lttng_consumer_local_data *ctx,
+ bool locked_by_caller)
+{
+ ssize_t ret, written_bytes = 0;
+ int rotation_ret;
+ struct stream_subbuffer subbuffer = {};
+
+ if (!locked_by_caller) {
+ stream->read_subbuffer_ops.lock(stream);
}
- if (stream->metadata_flag) {
- pthread_cond_broadcast(&stream->metadata_rdv);
- pthread_mutex_unlock(&stream->metadata_rdv_lock);
+ if (stream->read_subbuffer_ops.on_wake_up) {
+ ret = stream->read_subbuffer_ops.on_wake_up(stream);
+ if (ret) {
+ goto end;
+ }
+ }
+
+ /*
+ * If the stream was flagged to be ready for rotation before we extract
+ * the next packet, rotate it now.
+ */
+ if (stream->rotate_ready) {
+ DBG("Rotate stream before consuming data");
+ ret = lttng_consumer_rotate_stream(ctx, stream);
+ if (ret < 0) {
+ ERR("Stream rotation error before consuming data");
+ goto end;
+ }
+ }
+
+ ret = stream->read_subbuffer_ops.get_next_subbuffer(stream, &subbuffer);
+ if (ret) {
+ if (ret == -ENODATA) {
+ /* Not an error. */
+ ret = 0;
+ goto sleep_stream;
+ }
+ goto end;
+ }
+
+ ret = stream->read_subbuffer_ops.pre_consume_subbuffer(
+ stream, &subbuffer);
+ if (ret) {
+ goto error_put_subbuf;
+ }
+
+ written_bytes = stream->read_subbuffer_ops.consume_subbuffer(
+ ctx, stream, &subbuffer);
+ if (written_bytes <= 0) {
+ ERR("Error consuming subbuffer: (%zd)", written_bytes);
+ ret = (int) written_bytes;
+ goto error_put_subbuf;
+ }
+
+ ret = stream->read_subbuffer_ops.put_next_subbuffer(stream, &subbuffer);
+ if (ret) {
+ goto end;
+ }
+
+ ret = post_consume(stream, &subbuffer, ctx);
+ if (ret) {
+ goto end;
+ }
+
+ /*
+ * After extracting the packet, we check if the stream is now ready to
+ * be rotated and perform the action immediately.
+ *
+ * Don't overwrite `ret` as callers expect the number of bytes
+ * consumed to be returned on success.
+ */
+ rotation_ret = lttng_consumer_stream_is_rotate_ready(stream);
+ if (rotation_ret == 1) {
+ rotation_ret = lttng_consumer_rotate_stream(ctx, stream);
+ if (rotation_ret < 0) {
+ ret = rotation_ret;
+ ERR("Stream rotation error after consuming data");
+ goto end;
+ }
+
+ } else if (rotation_ret < 0) {
+ ret = rotation_ret;
+ ERR("Failed to check if stream was ready to rotate after consuming data");
+ goto end;
+ }
+
+sleep_stream:
+ if (stream->read_subbuffer_ops.on_sleep) {
+ stream->read_subbuffer_ops.on_sleep(stream, ctx);
+ }
+
+ ret = written_bytes;
+end:
+ if (!locked_by_caller) {
+ stream->read_subbuffer_ops.unlock(stream);
}
- pthread_mutex_unlock(&stream->lock);
- pthread_mutex_unlock(&stream->chan->lock);
return ret;
+error_put_subbuf:
+ (void) stream->read_subbuffer_ops.put_next_subbuffer(stream, &subbuffer);
+ goto end;
}
int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream)
return start_pos;
}
-static
-int consumer_flush_buffer(struct lttng_consumer_stream *stream, int producer_active)
+/* Stream lock must be held by the caller. */
+static int sample_stream_positions(struct lttng_consumer_stream *stream,
+ unsigned long *produced, unsigned long *consumed)
{
- int ret = 0;
+ int ret;
- switch (consumer_data.type) {
- case LTTNG_CONSUMER_KERNEL:
- if (producer_active) {
- ret = kernctl_buffer_flush(stream->wait_fd);
- if (ret < 0) {
- ERR("Failed to flush kernel stream");
- goto end;
- }
- } else {
- ret = kernctl_buffer_flush_empty(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();
+ ASSERT_LOCKED(stream->lock);
+
+ ret = lttng_consumer_sample_snapshot_positions(stream);
+ if (ret < 0) {
+ ERR("Failed to sample snapshot positions");
+ goto end;
+ }
+
+ ret = lttng_consumer_get_produced_snapshot(stream, produced);
+ if (ret < 0) {
+ ERR("Failed to sample produced position");
+ goto end;
+ }
+
+ ret = lttng_consumer_get_consumed_snapshot(stream, consumed);
+ if (ret < 0) {
+ ERR("Failed to sample consumed position");
+ goto end;
}
end:
const bool is_local_trace = relayd_id == -1ULL;
struct consumer_relayd_sock_pair *relayd = NULL;
bool rotating_to_new_chunk = true;
+ /* Array of `struct lttng_consumer_stream *` */
+ struct lttng_dynamic_pointer_array streams_packet_to_open;
+ size_t stream_idx;
DBG("Consumer sample rotate position for channel %" PRIu64, key);
lttng_dynamic_array_init(&stream_rotation_positions,
sizeof(struct relayd_stream_rotation_position), NULL);
+ lttng_dynamic_pointer_array_init(&streams_packet_to_open, NULL);
rcu_read_lock();
}
/*
- * Do not flush an empty packet when rotating from a NULL trace
+ * Do not flush a packet when rotating from a NULL trace
* chunk. The stream has no means to output data, and the prior
- * rotation which rotated to NULL performed that side-effect already.
+ * rotation which rotated to NULL performed that side-effect
+ * already. No new data can be produced when a stream has no
+ * associated trace chunk (e.g. a stop followed by a rotate).
*/
if (stream->trace_chunk) {
+ bool flush_active;
+
+ if (stream->metadata_flag) {
+ /*
+ * Don't produce an empty metadata packet,
+ * simply close the current one.
+ *
+ * Metadata is regenerated on every trace chunk
+ * switch; there is no concern that no data was
+ * produced.
+ */
+ flush_active = true;
+ } else {
+ /*
+ * Only flush an empty packet if the "packet
+ * open" could not be performed on transition
+ * to a new trace chunk and no packets were
+ * consumed within the chunk's lifetime.
+ */
+ if (stream->opened_packet_in_current_trace_chunk) {
+ flush_active = true;
+ } else {
+ /*
+ * Stream could have been full at the
+ * time of rotation, but then have had
+ * no activity at all.
+ *
+ * It is important to flush a packet
+ * to prevent 0-length files from being
+ * produced as most viewers choke on
+ * them.
+ *
+ * Unfortunately viewers will not be
+ * able to know that tracing was active
+ * for this stream during this trace
+ * chunk's lifetime.
+ */
+ ret = sample_stream_positions(stream, &produced_pos, &consumed_pos);
+ if (ret) {
+ goto end_unlock_stream;
+ }
+
+ /*
+ * Don't flush an empty packet if data
+ * was produced; it will be consumed
+ * before the rotation completes.
+ */
+ flush_active = produced_pos != consumed_pos;
+ if (!flush_active) {
+ enum lttng_trace_chunk_status chunk_status;
+ const char *trace_chunk_name;
+ uint64_t trace_chunk_id;
+
+ chunk_status = lttng_trace_chunk_get_name(
+ stream->trace_chunk,
+ &trace_chunk_name,
+ NULL);
+ if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_NONE) {
+ trace_chunk_name = "none";
+ }
+
+ /*
+ * Consumer trace chunks are
+ * never anonymous.
+ */
+ chunk_status = lttng_trace_chunk_get_id(
+ stream->trace_chunk,
+ &trace_chunk_id);
+ assert(chunk_status ==
+ LTTNG_TRACE_CHUNK_STATUS_OK);
+
+ DBG("Unable to open packet for stream during trace chunk's lifetime. "
+ "Flushing an empty packet to prevent an empty file from being created: "
+ "stream id = %" PRIu64 ", trace chunk name = `%s`, trace chunk id = %" PRIu64,
+ stream->key, trace_chunk_name, trace_chunk_id);
+ }
+ }
+ }
+
/*
- * For metadata stream, do an active flush, which does not
- * produce empty packets. For data streams, empty-flush;
- * ensures we have at least one packet in each stream per trace
- * chunk, even if no data was produced.
+ * Close the current packet before sampling the
+ * ring buffer positions.
*/
- ret = consumer_flush_buffer(stream, stream->metadata_flag ? 1 : 0);
+ ret = consumer_stream_flush_buffer(stream, flush_active);
if (ret < 0) {
ERR("Failed to flush stream %" PRIu64 " during channel rotation",
stream->key);
*/
produced_pos = ALIGN_FLOOR(produced_pos, stream->max_sb_size);
if (consumed_pos == produced_pos) {
+ DBG("Set rotate ready for stream %" PRIu64 " produced = %lu consumed = %lu",
+ stream->key, produced_pos, consumed_pos);
stream->rotate_ready = true;
+ } else {
+ DBG("Different consumed and produced positions "
+ "for stream %" PRIu64 " produced = %lu consumed = %lu",
+ stream->key, produced_pos, consumed_pos);
}
/*
* The rotation position is based on the packet_seq_num of the
}
stream->rotate_position = stream->last_sequence_number + 1 +
((produced_pos - consumed_pos) / stream->max_sb_size);
+ DBG("Set rotation position for stream %" PRIu64 " at position %" PRIu64,
+ stream->key, stream->rotate_position);
if (!is_local_trace) {
/*
}
stream_count++;
}
+
+ stream->opened_packet_in_current_trace_chunk = false;
+
+ if (rotating_to_new_chunk && !stream->metadata_flag) {
+ /*
+ * Attempt to flush an empty packet as close to the
+ * rotation point as possible. In the event where a
+ * stream remains inactive after the rotation point,
+ * this ensures that the new trace chunk has a
+ * beginning timestamp set at the begining of the
+ * trace chunk instead of only creating an empty
+ * packet when the trace chunk is stopped.
+ *
+ * This indicates to the viewers that the stream
+ * was being recorded, but more importantly it
+ * allows viewers to determine a useable trace
+ * intersection.
+ *
+ * This presents a problem in the case where the
+ * ring-buffer is completely full.
+ *
+ * Consider the following scenario:
+ * - The consumption of data is slow (slow network,
+ * for instance),
+ * - The ring buffer is full,
+ * - A rotation is initiated,
+ * - The flush below does nothing (no space left to
+ * open a new packet),
+ * - The other streams rotate very soon, and new
+ * data is produced in the new chunk,
+ * - This stream completes its rotation long after the
+ * rotation was initiated
+ * - The session is stopped before any event can be
+ * produced in this stream's buffers.
+ *
+ * The resulting trace chunk will have a single packet
+ * temporaly at the end of the trace chunk for this
+ * stream making the stream intersection more narrow
+ * than it should be.
+ *
+ * To work-around this, an empty flush is performed
+ * after the first consumption of a packet during a
+ * rotation if open_packet fails. The idea is that
+ * consuming a packet frees enough space to switch
+ * packets in this scenario and allows the tracer to
+ * "stamp" the beginning of the new trace chunk at the
+ * earliest possible point.
+ *
+ * The packet open is performed after the channel
+ * rotation to ensure that no attempt to open a packet
+ * is performed in a stream that has no active trace
+ * chunk.
+ */
+ ret = lttng_dynamic_pointer_array_add_pointer(
+ &streams_packet_to_open, stream);
+ if (ret) {
+ PERROR("Failed to add a stream pointer to array of streams in which to open a packet");
+ ret = -1;
+ goto end_unlock_stream;
+ }
+ }
+
pthread_mutex_unlock(&stream->lock);
}
stream = NULL;
- pthread_mutex_unlock(&channel->lock);
- if (is_local_trace) {
- ret = 0;
- goto end;
- }
+ if (!is_local_trace) {
+ relayd = consumer_find_relayd(relayd_id);
+ if (!relayd) {
+ ERR("Failed to find relayd %" PRIu64, relayd_id);
+ ret = -1;
+ goto end_unlock_channel;
+ }
- relayd = consumer_find_relayd(relayd_id);
- if (!relayd) {
- ERR("Failed to find relayd %" PRIu64, relayd_id);
- ret = -1;
- goto end;
+ pthread_mutex_lock(&relayd->ctrl_sock_mutex);
+ ret = relayd_rotate_streams(&relayd->control_sock, stream_count,
+ rotating_to_new_chunk ? &next_chunk_id : NULL,
+ (const struct relayd_stream_rotation_position *)
+ stream_rotation_positions.buffer
+ .data);
+ pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
+ if (ret < 0) {
+ ERR("Relayd rotate stream failed. Cleaning up relayd %" PRIu64,
+ relayd->net_seq_idx);
+ lttng_consumer_cleanup_relayd(relayd);
+ goto end_unlock_channel;
+ }
}
- pthread_mutex_lock(&relayd->ctrl_sock_mutex);
- ret = relayd_rotate_streams(&relayd->control_sock, stream_count,
- rotating_to_new_chunk ? &next_chunk_id : NULL,
- (const struct relayd_stream_rotation_position *)
- stream_rotation_positions.buffer.data);
- pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
- if (ret < 0) {
- ERR("Relayd rotate stream failed. Cleaning up relayd %" PRIu64,
- relayd->net_seq_idx);
- lttng_consumer_cleanup_relayd(relayd);
- goto end;
+ for (stream_idx = 0;
+ stream_idx < lttng_dynamic_pointer_array_get_count(
+ &streams_packet_to_open);
+ stream_idx++) {
+ enum consumer_stream_open_packet_status status;
+
+ stream = lttng_dynamic_pointer_array_get_pointer(
+ &streams_packet_to_open, stream_idx);
+
+ pthread_mutex_lock(&stream->lock);
+ status = consumer_stream_open_packet(stream);
+ pthread_mutex_unlock(&stream->lock);
+ switch (status) {
+ case CONSUMER_STREAM_OPEN_PACKET_STATUS_OPENED:
+ DBG("Opened a packet after a rotation: stream id = %" PRIu64
+ ", channel name = %s, session id = %" PRIu64,
+ stream->key, stream->chan->name,
+ stream->chan->session_id);
+ break;
+ case CONSUMER_STREAM_OPEN_PACKET_STATUS_NO_SPACE:
+ /*
+ * Can't open a packet as there is no space left
+ * in the buffer. A new packet will be opened
+ * once one has been consumed.
+ */
+ DBG("No space left to open a packet after a rotation: stream id = %" PRIu64
+ ", channel name = %s, session id = %" PRIu64,
+ stream->key, stream->chan->name,
+ stream->chan->session_id);
+ break;
+ case CONSUMER_STREAM_OPEN_PACKET_STATUS_ERROR:
+ /* Logged by callee. */
+ ret = -1;
+ goto end_unlock_channel;
+ default:
+ abort();
+ }
}
+ pthread_mutex_unlock(&channel->lock);
ret = 0;
goto end;
end:
rcu_read_unlock();
lttng_dynamic_array_reset(&stream_rotation_positions);
+ lttng_dynamic_pointer_array_reset(&streams_packet_to_open);
+ return ret;
+}
+
+static
+int consumer_clear_buffer(struct lttng_consumer_stream *stream)
+{
+ int ret = 0;
+ unsigned long consumed_pos_before, consumed_pos_after;
+
+ ret = lttng_consumer_sample_snapshot_positions(stream);
+ if (ret < 0) {
+ ERR("Taking snapshot positions");
+ goto end;
+ }
+
+ ret = lttng_consumer_get_consumed_snapshot(stream, &consumed_pos_before);
+ if (ret < 0) {
+ ERR("Consumed snapshot position");
+ goto end;
+ }
+
+ switch (consumer_data.type) {
+ case LTTNG_CONSUMER_KERNEL:
+ ret = kernctl_buffer_clear(stream->wait_fd);
+ if (ret < 0) {
+ ERR("Failed to clear kernel stream (ret = %d)", ret);
+ goto end;
+ }
+ break;
+ case LTTNG_CONSUMER32_UST:
+ case LTTNG_CONSUMER64_UST:
+ lttng_ustconsumer_clear_buffer(stream);
+ break;
+ default:
+ ERR("Unknown consumer_data type");
+ abort();
+ }
+
+ ret = lttng_consumer_sample_snapshot_positions(stream);
+ if (ret < 0) {
+ ERR("Taking snapshot positions");
+ goto end;
+ }
+ ret = lttng_consumer_get_consumed_snapshot(stream, &consumed_pos_after);
+ if (ret < 0) {
+ ERR("Consumed snapshot position");
+ goto end;
+ }
+ DBG("clear: before: %lu after: %lu", consumed_pos_before, consumed_pos_after);
+end:
+ return ret;
+}
+
+static
+int consumer_clear_stream(struct lttng_consumer_stream *stream)
+{
+ int ret;
+
+ ret = consumer_stream_flush_buffer(stream, 1);
+ if (ret < 0) {
+ ERR("Failed to flush stream %" PRIu64 " during channel clear",
+ stream->key);
+ ret = LTTCOMM_CONSUMERD_FATAL;
+ goto error;
+ }
+
+ 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;
+ }
+
+ ret = LTTCOMM_CONSUMERD_SUCCESS;
+error:
+ return ret;
+}
+
+static
+int consumer_clear_unmonitored_channel(struct lttng_consumer_channel *channel)
+{
+ int ret;
+ struct lttng_consumer_stream *stream;
+
+ 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_clear_stream(stream);
+ if (ret) {
+ 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_stream_is_rotate_ready(struct lttng_consumer_stream *stream)
{
+ DBG("Check is rotate ready for stream %" PRIu64
+ " ready %u rotate_position %" PRIu64
+ " last_sequence_number %" PRIu64,
+ stream->key, stream->rotate_ready,
+ stream->rotate_position, stream->last_sequence_number);
if (stream->rotate_ready) {
return 1;
}
* but consumerd considers rotation ready when reaching the last
* packet of the current chunk, hence the "rotate_position - 1".
*/
+
+ DBG("Check is rotate ready for stream %" PRIu64
+ " last_sequence_number %" PRIu64
+ " rotate_position %" PRIu64,
+ stream->key, stream->last_sequence_number,
+ stream->rotate_position);
if (stream->last_sequence_number >= stream->rotate_position - 1) {
return 1;
}
*/
void lttng_consumer_reset_stream_rotate_state(struct lttng_consumer_stream *stream)
{
+ DBG("lttng_consumer_reset_stream_rotate_state for stream %" PRIu64,
+ stream->key);
stream->rotate_position = -1ULL;
stream->rotate_ready = false;
}
} else {
relayd_id_str = "(formatting error)";
}
- }
+ }
- /* Local protocol error. */
+ /* Local protocol error. */
assert(chunk_creation_timestamp);
ret = time_to_iso8601_str(chunk_creation_timestamp,
creation_timestamp_buffer,
* and LTTNG_CONSUMER_DESTROY_TRACE_CHUNK commands.
*/
created_chunk = lttng_trace_chunk_create(chunk_id,
- chunk_creation_timestamp);
+ chunk_creation_timestamp, NULL);
if (!created_chunk) {
ERR("Failed to create trace chunk");
ret_code = LTTCOMM_CONSUMERD_CREATE_TRACE_CHUNK_FAILED;
} else {
relayd_id_str = "(formatting error)";
}
- }
+ }
DBG("Consumer trace chunk exists command: relayd_id = %s"
", chunk_id = %" PRIu64, relayd_id_str,
end:
return ret_code;
}
+
+static
+int consumer_clear_monitored_channel(struct lttng_consumer_channel *channel)
+{
+ struct lttng_ht *ht;
+ struct lttng_consumer_stream *stream;
+ struct lttng_ht_iter iter;
+ int ret;
+
+ ht = consumer_data.stream_per_chan_id_ht;
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry_duplicate(ht->ht,
+ ht->hash_fct(&channel->key, lttng_ht_seed),
+ ht->match_fct, &channel->key,
+ &iter.iter, stream, node_channel_id.node) {
+ /*
+ * Protect against teardown with mutex.
+ */
+ pthread_mutex_lock(&stream->lock);
+ if (cds_lfht_is_node_deleted(&stream->node.node)) {
+ goto next;
+ }
+ ret = consumer_clear_stream(stream);
+ if (ret) {
+ goto error_unlock;
+ }
+ next:
+ pthread_mutex_unlock(&stream->lock);
+ }
+ rcu_read_unlock();
+ return LTTCOMM_CONSUMERD_SUCCESS;
+
+error_unlock:
+ pthread_mutex_unlock(&stream->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->type == CONSUMER_CHANNEL_TYPE_METADATA) {
+ /*
+ * Nothing to do for the metadata channel/stream.
+ * Snapshot mechanism already take care of the metadata
+ * handling/generation, and monitored channels only need to
+ * have their data stream cleared..
+ */
+ ret = LTTCOMM_CONSUMERD_SUCCESS;
+ goto end;
+ }
+
+ if (!channel->monitor) {
+ ret = consumer_clear_unmonitored_channel(channel);
+ } else {
+ ret = consumer_clear_monitored_channel(channel);
+ }
+end:
+ return ret;
+}
+
+enum lttcomm_return_code lttng_consumer_open_channel_packets(
+ struct lttng_consumer_channel *channel)
+{
+ struct lttng_consumer_stream *stream;
+ enum lttcomm_return_code ret = LTTCOMM_CONSUMERD_SUCCESS;
+
+ if (channel->metadata_stream) {
+ ERR("Open channel packets command attempted on a metadata channel");
+ ret = LTTCOMM_CONSUMERD_INVALID_PARAMETERS;
+ goto end;
+ }
+
+ rcu_read_lock();
+ cds_list_for_each_entry(stream, &channel->streams.head, send_node) {
+ enum consumer_stream_open_packet_status status;
+
+ pthread_mutex_lock(&stream->lock);
+ if (cds_lfht_is_node_deleted(&stream->node.node)) {
+ goto next;
+ }
+
+ status = consumer_stream_open_packet(stream);
+ switch (status) {
+ case CONSUMER_STREAM_OPEN_PACKET_STATUS_OPENED:
+ DBG("Opened a packet in \"open channel packets\" command: stream id = %" PRIu64
+ ", channel name = %s, session id = %" PRIu64,
+ stream->key, stream->chan->name,
+ stream->chan->session_id);
+ stream->opened_packet_in_current_trace_chunk = true;
+ break;
+ case CONSUMER_STREAM_OPEN_PACKET_STATUS_NO_SPACE:
+ DBG("No space left to open a packet in \"open channel packets\" command: stream id = %" PRIu64
+ ", channel name = %s, session id = %" PRIu64,
+ stream->key, stream->chan->name,
+ stream->chan->session_id);
+ break;
+ case CONSUMER_STREAM_OPEN_PACKET_STATUS_ERROR:
+ /*
+ * Only unexpected internal errors can lead to this
+ * failing. Report an unknown error.
+ */
+ ERR("Failed to flush empty buffer in \"open channel packets\" command: stream id = %" PRIu64
+ ", channel id = %" PRIu64
+ ", channel name = %s"
+ ", session id = %" PRIu64,
+ stream->key, channel->key,
+ channel->name, channel->session_id);
+ ret = LTTCOMM_CONSUMERD_UNKNOWN_ERROR;
+ goto error_unlock;
+ default:
+ abort();
+ }
+
+ next:
+ pthread_mutex_unlock(&stream->lock);
+ }
+
+end_rcu_unlock:
+ rcu_read_unlock();
+end:
+ return ret;
+
+error_unlock:
+ pthread_mutex_unlock(&stream->lock);
+ goto end_rcu_unlock;
+}