#include <inttypes.h>
#include <common/common.h>
+#include <common/utils.h>
+#include <common/compat/poll.h>
#include <common/kernel-ctl/kernel-ctl.h>
#include <common/sessiond-comm/relayd.h>
#include <common/sessiond-comm/sessiond-comm.h>
consumer_data.stream_count++;
consumer_data.need_update = 1;
- switch (consumer_data.type) {
- case LTTNG_CONSUMER_KERNEL:
- break;
- case LTTNG_CONSUMER32_UST:
- case LTTNG_CONSUMER64_UST:
- /* Streams are in CPU number order (we rely on this) */
- stream->cpu = stream->chan->nr_streams++;
- break;
- default:
- ERR("Unknown consumer_data type");
- assert(0);
- goto end;
- }
-
end:
pthread_mutex_unlock(&consumer_data.lock);
channel->mmap_len = mmap_len;
channel->max_sb_size = max_sb_size;
channel->refcount = 0;
- channel->nr_streams = 0;
lttng_ht_node_init_ulong(&channel->node, channel->key);
switch (consumer_data.type) {
*/
int consumer_update_poll_array(
struct lttng_consumer_local_data *ctx, struct pollfd **pollfd,
- struct lttng_consumer_stream **local_stream,
- struct lttng_ht *metadata_ht)
+ struct lttng_consumer_stream **local_stream)
{
int i = 0;
struct lttng_ht_iter iter;
DBG("Active FD %d", stream->wait_fd);
(*pollfd)[i].fd = stream->wait_fd;
(*pollfd)[i].events = POLLIN | POLLPRI;
- if (stream->metadata_flag && metadata_ht) {
- lttng_ht_add_unique_ulong(metadata_ht, &stream->waitfd_node);
- DBG("Active FD added to metadata hash table");
- }
local_stream[i] = stream;
i++;
}
goto error_thread_pipe;
}
- return ctx;
+ ret = utils_create_pipe(ctx->consumer_metadata_pipe);
+ if (ret < 0) {
+ goto error_metadata_pipe;
+ }
+ ret = utils_create_pipe(ctx->consumer_splice_metadata_pipe);
+ if (ret < 0) {
+ goto error_splice_pipe;
+ }
+
+ return ctx;
+error_splice_pipe:
+ utils_close_pipe(ctx->consumer_metadata_pipe);
+error_metadata_pipe:
+ utils_close_pipe(ctx->consumer_thread_pipe);
error_thread_pipe:
for (i = 0; i < 2; i++) {
int err;
if (ret) {
PERROR("close");
}
+ utils_close_pipe(ctx->consumer_splice_metadata_pipe);
+
unlink(ctx->consumer_command_sock_path);
free(ctx);
}
/* Default is on the disk */
int outfd = stream->out_fd;
struct consumer_relayd_sock_pair *relayd = NULL;
+ int *splice_pipe;
switch (consumer_data.type) {
case LTTNG_CONSUMER_KERNEL:
}
}
+ /*
+ * Choose right pipe for splice. Metadata and trace data are handled by
+ * different threads hence the use of two pipes in order not to race or
+ * corrupt the written data.
+ */
+ if (stream->metadata_flag) {
+ splice_pipe = ctx->consumer_splice_metadata_pipe;
+ } else {
+ splice_pipe = ctx->consumer_thread_pipe;
+ }
+
/* Write metadata stream id before payload */
if (stream->metadata_flag && relayd) {
/*
*/
pthread_mutex_lock(&relayd->ctrl_sock_mutex);
- ret = write_relayd_metadata_id(ctx->consumer_thread_pipe[1],
- stream, relayd);
+ ret = write_relayd_metadata_id(splice_pipe[1], stream, relayd);
if (ret < 0) {
written = ret;
goto end;
while (len > 0) {
DBG("splice chan to pipe offset %lu of len %lu (fd : %d)",
(unsigned long)offset, len, fd);
- ret_splice = splice(fd, &offset, ctx->consumer_thread_pipe[1], NULL, len,
+ ret_splice = splice(fd, &offset, splice_pipe[1], NULL, len,
SPLICE_F_MOVE | SPLICE_F_MORE);
DBG("splice chan to pipe, ret %zd", ret_splice);
if (ret_splice < 0) {
}
/* Splice data out */
- ret_splice = splice(ctx->consumer_thread_pipe[0], NULL, outfd, NULL,
+ ret_splice = splice(splice_pipe[0], NULL, outfd, NULL,
ret_splice, SPLICE_F_MOVE | SPLICE_F_MORE);
DBG("Kernel consumer splice pipe to file, ret %zd", ret_splice);
if (ret_splice < 0) {
}
}
+/*
+ * Iterate over all stream element of the hashtable and free them. This is race
+ * free since the hashtable received MUST be in a race free synchronization
+ * state. It's the caller responsability to make sure of that.
+ */
+static void destroy_stream_ht(struct lttng_ht *ht)
+{
+ int ret;
+ struct lttng_ht_iter iter;
+ struct lttng_consumer_stream *stream;
+
+ if (ht == NULL) {
+ return;
+ }
+
+ cds_lfht_for_each_entry(ht->ht, &iter.iter, stream, node.node) {
+ ret = lttng_ht_del(ht, &iter);
+ assert(!ret);
+
+ free(stream);
+ }
+
+ lttng_ht_destroy(ht);
+}
+
+/*
+ * Clean up a metadata stream and free its memory.
+ */
+static void consumer_del_metadata_stream(struct lttng_consumer_stream *stream)
+{
+ int ret;
+ struct lttng_consumer_channel *free_chan = NULL;
+ struct consumer_relayd_sock_pair *relayd;
+
+ assert(stream);
+ /*
+ * This call should NEVER receive regular stream. It must always be
+ * metadata stream and this is crucial for data structure synchronization.
+ */
+ assert(stream->metadata_flag);
+
+ pthread_mutex_lock(&consumer_data.lock);
+ switch (consumer_data.type) {
+ case LTTNG_CONSUMER_KERNEL:
+ if (stream->mmap_base != NULL) {
+ ret = munmap(stream->mmap_base, stream->mmap_len);
+ if (ret != 0) {
+ PERROR("munmap metadata stream");
+ }
+ }
+ break;
+ case LTTNG_CONSUMER32_UST:
+ case LTTNG_CONSUMER64_UST:
+ lttng_ustconsumer_del_stream(stream);
+ break;
+ default:
+ ERR("Unknown consumer_data type");
+ assert(0);
+ }
+ pthread_mutex_unlock(&consumer_data.lock);
+
+ if (stream->out_fd >= 0) {
+ ret = close(stream->out_fd);
+ if (ret) {
+ PERROR("close");
+ }
+ }
+
+ if (stream->wait_fd >= 0 && !stream->wait_fd_is_copy) {
+ ret = close(stream->wait_fd);
+ if (ret) {
+ PERROR("close");
+ }
+ }
+
+ if (stream->shm_fd >= 0 && stream->wait_fd != stream->shm_fd) {
+ ret = close(stream->shm_fd);
+ if (ret) {
+ PERROR("close");
+ }
+ }
+
+ /* Check and cleanup relayd */
+ rcu_read_lock();
+ relayd = consumer_find_relayd(stream->net_seq_idx);
+ if (relayd != NULL) {
+ uatomic_dec(&relayd->refcount);
+ assert(uatomic_read(&relayd->refcount) >= 0);
+
+ /* Closing streams requires to lock the control socket. */
+ pthread_mutex_lock(&relayd->ctrl_sock_mutex);
+ ret = relayd_send_close_stream(&relayd->control_sock,
+ stream->relayd_stream_id, stream->next_net_seq_num - 1);
+ pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
+ if (ret < 0) {
+ DBG("Unable to close stream on the relayd. Continuing");
+ /*
+ * Continue here. There is nothing we can do for the relayd.
+ * Chances are that the relayd has closed the socket so we just
+ * continue cleaning up.
+ */
+ }
+
+ /* Both conditions are met, we destroy the relayd. */
+ if (uatomic_read(&relayd->refcount) == 0 &&
+ uatomic_read(&relayd->destroy_flag)) {
+ consumer_destroy_relayd(relayd);
+ }
+ }
+ rcu_read_unlock();
+
+ /* Atomically decrement channel refcount since other threads can use it. */
+ uatomic_dec(&stream->chan->refcount);
+ if (!uatomic_read(&stream->chan->refcount)) {
+ free_chan = stream->chan;
+ }
+
+ if (free_chan) {
+ consumer_del_channel(free_chan);
+ }
+
+ free(stream);
+}
+
+/*
+ * Action done with the metadata stream when adding it to the consumer internal
+ * data structures to handle it.
+ */
+static void consumer_add_metadata_stream(struct lttng_consumer_stream *stream)
+{
+ struct consumer_relayd_sock_pair *relayd;
+
+ /* Find relayd and, if one is found, increment refcount. */
+ rcu_read_lock();
+ relayd = consumer_find_relayd(stream->net_seq_idx);
+ if (relayd != NULL) {
+ uatomic_inc(&relayd->refcount);
+ }
+ rcu_read_unlock();
+}
+
+/*
+ * Thread polls on metadata file descriptor and write them on disk or on the
+ * network.
+ */
+void *lttng_consumer_thread_poll_metadata(void *data)
+{
+ int ret, i, pollfd;
+ uint32_t revents, nb_fd;
+ struct lttng_consumer_stream *stream;
+ struct lttng_ht_iter iter;
+ struct lttng_ht_node_ulong *node;
+ struct lttng_ht *metadata_ht = NULL;
+ struct lttng_poll_event events;
+ struct lttng_consumer_local_data *ctx = data;
+ ssize_t len;
+
+ rcu_register_thread();
+
+ DBG("Thread metadata poll started");
+
+ metadata_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
+ if (metadata_ht == NULL) {
+ goto end;
+ }
+
+ /* Size is set to 1 for the consumer_metadata pipe */
+ ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
+ if (ret < 0) {
+ ERR("Poll set creation failed");
+ goto end;
+ }
+
+ ret = lttng_poll_add(&events, ctx->consumer_metadata_pipe[0], LPOLLIN);
+ if (ret < 0) {
+ goto end;
+ }
+
+ /* Main loop */
+ DBG("Metadata main loop started");
+
+ while (1) {
+ lttng_poll_reset(&events);
+
+ nb_fd = LTTNG_POLL_GETNB(&events);
+
+ /* Only the metadata pipe is set */
+ if (nb_fd == 0 && consumer_quit == 1) {
+ goto end;
+ }
+
+restart:
+ DBG("Metadata poll wait with %d fd(s)", nb_fd);
+ ret = lttng_poll_wait(&events, -1);
+ DBG("Metadata event catched in thread");
+ if (ret < 0) {
+ if (errno == EINTR) {
+ goto restart;
+ }
+ goto error;
+ }
+
+ for (i = 0; i < nb_fd; i++) {
+ revents = LTTNG_POLL_GETEV(&events, i);
+ pollfd = LTTNG_POLL_GETFD(&events, i);
+
+ /* Check the metadata pipe for incoming metadata. */
+ if (pollfd == ctx->consumer_metadata_pipe[0]) {
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLNVAL)) {
+ DBG("Metadata thread pipe hung up");
+ /*
+ * Remove the pipe from the poll set and continue the loop
+ * since their might be data to consume.
+ */
+ lttng_poll_del(&events, ctx->consumer_metadata_pipe[0]);
+ close(ctx->consumer_metadata_pipe[0]);
+ continue;
+ } else if (revents & LPOLLIN) {
+ stream = zmalloc(sizeof(struct lttng_consumer_stream));
+ if (stream == NULL) {
+ PERROR("zmalloc metadata consumer stream");
+ goto error;
+ }
+
+ do {
+ /* Get the stream and add it to the local hash table */
+ ret = read(pollfd, stream,
+ sizeof(struct lttng_consumer_stream));
+ } while (ret < 0 && errno == EINTR);
+ if (ret < 0 || ret < sizeof(struct lttng_consumer_stream)) {
+ PERROR("read metadata stream");
+ free(stream);
+ /*
+ * Let's continue here and hope we can still work
+ * without stopping the consumer. XXX: Should we?
+ */
+ continue;
+ }
+
+ DBG("Adding metadata stream %d to poll set",
+ stream->wait_fd);
+
+ /* The node should be init at this point */
+ lttng_ht_add_unique_ulong(metadata_ht,
+ &stream->waitfd_node);
+
+ /* Add metadata stream to the global poll events list */
+ lttng_poll_add(&events, stream->wait_fd,
+ LPOLLIN | LPOLLPRI);
+
+ consumer_add_metadata_stream(stream);
+ }
+
+ /* Metadata pipe handled. Continue handling the others */
+ continue;
+ }
+
+ /* From here, the event is a metadata wait fd */
+
+ lttng_ht_lookup(metadata_ht, (void *)((unsigned long) pollfd),
+ &iter);
+ node = lttng_ht_iter_get_node_ulong(&iter);
+ if (node == NULL) {
+ /* FD not found, continue loop */
+ continue;
+ }
+
+ stream = caa_container_of(node, struct lttng_consumer_stream,
+ waitfd_node);
+
+ /* Get the data out of the metadata file descriptor */
+ if (revents & (LPOLLIN | LPOLLPRI)) {
+ DBG("Metadata available on fd %d", pollfd);
+ assert(stream->wait_fd == pollfd);
+
+ len = ctx->on_buffer_ready(stream, ctx);
+ /* It's ok to have an unavailable sub-buffer */
+ if (len < 0 && len != -EAGAIN) {
+ goto end;
+ } else if (len > 0) {
+ stream->data_read = 1;
+ }
+ }
+
+ /*
+ * Remove the stream from the hash table since there is no data
+ * left on the fd because we previously did a read on the buffer.
+ */
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLNVAL)) {
+ DBG("Metadata fd %d is hup|err|nval.", pollfd);
+ if (!stream->hangup_flush_done
+ && (consumer_data.type == LTTNG_CONSUMER32_UST
+ || consumer_data.type == LTTNG_CONSUMER64_UST)) {
+ DBG("Attempting to flush and consume the UST buffers");
+ lttng_ustconsumer_on_stream_hangup(stream);
+
+ /* We just flushed the stream now read it. */
+ len = ctx->on_buffer_ready(stream, ctx);
+ /* It's ok to have an unavailable sub-buffer */
+ if (len < 0 && len != -EAGAIN) {
+ goto end;
+ }
+ }
+
+ /* Removing it from hash table, poll set and free memory */
+ lttng_ht_del(metadata_ht, &iter);
+ lttng_poll_del(&events, stream->wait_fd);
+ consumer_del_metadata_stream(stream);
+ }
+ }
+ }
+
+error:
+end:
+ DBG("Metadata poll thread exiting");
+ lttng_poll_clean(&events);
+
+ if (metadata_ht) {
+ destroy_stream_ht(metadata_ht);
+ }
+
+ rcu_unregister_thread();
+ return NULL;
+}
+
/*
* This thread polls the fds in the set to consume the data and write
* it to tracefile if necessary.
/* local view of consumer_data.fds_count */
int nb_fd = 0;
struct lttng_consumer_local_data *ctx = data;
- struct lttng_ht *metadata_ht;
- struct lttng_ht_iter iter;
- struct lttng_ht_node_ulong *node;
- struct lttng_consumer_stream *metadata_stream;
ssize_t len;
-
- metadata_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
+ pthread_t metadata_thread;
+ void *status;
rcu_register_thread();
+ /* Start metadata polling thread */
+ ret = pthread_create(&metadata_thread, NULL,
+ lttng_consumer_thread_poll_metadata, (void *) ctx);
+ if (ret < 0) {
+ PERROR("pthread_create metadata thread");
+ goto end;
+ }
+
local_stream = zmalloc(sizeof(struct lttng_consumer_stream));
while (1) {
pthread_mutex_unlock(&consumer_data.lock);
goto end;
}
- ret = consumer_update_poll_array(ctx, &pollfd, local_stream,
- metadata_ht);
+ ret = consumer_update_poll_array(ctx, &pollfd, local_stream);
if (ret < 0) {
ERR("Error in allocating pollfd or local_outfds");
lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_POLL_ERROR);
/* Take care of high priority channels first. */
for (i = 0; i < nb_fd; i++) {
- /* Lookup for metadata which is the highest priority */
- lttng_ht_lookup(metadata_ht,
- (void *)((unsigned long) pollfd[i].fd), &iter);
- node = lttng_ht_iter_get_node_ulong(&iter);
- if (node != NULL &&
- (pollfd[i].revents & (POLLIN | POLLPRI))) {
- DBG("Urgent metadata read on fd %d", pollfd[i].fd);
- metadata_stream = caa_container_of(node,
- struct lttng_consumer_stream, waitfd_node);
- high_prio = 1;
- len = ctx->on_buffer_ready(metadata_stream, ctx);
- /* it's ok to have an unavailable sub-buffer */
- if (len < 0 && len != -EAGAIN) {
- goto end;
- } else if (len > 0) {
- metadata_stream->data_read = 1;
- }
- } else if (pollfd[i].revents & POLLPRI) {
+ 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);
if ((pollfd[i].revents & POLLHUP)) {
DBG("Polling fd %d tells it has hung up.", pollfd[i].fd);
if (!local_stream[i]->data_read) {
- if (local_stream[i]->metadata_flag) {
- iter.iter.node = &local_stream[i]->waitfd_node.node;
- ret = lttng_ht_del(metadata_ht, &iter);
- assert(!ret);
- }
consumer_del_stream(local_stream[i]);
num_hup++;
}
} else if (pollfd[i].revents & POLLERR) {
ERR("Error returned in polling fd %d.", pollfd[i].fd);
if (!local_stream[i]->data_read) {
- if (local_stream[i]->metadata_flag) {
- iter.iter.node = &local_stream[i]->waitfd_node.node;
- ret = lttng_ht_del(metadata_ht, &iter);
- assert(!ret);
- }
consumer_del_stream(local_stream[i]);
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) {
- if (local_stream[i]->metadata_flag) {
- iter.iter.node = &local_stream[i]->waitfd_node.node;
- ret = lttng_ht_del(metadata_ht, &iter);
- assert(!ret);
- }
consumer_del_stream(local_stream[i]);
num_hup++;
}
free(local_stream);
local_stream = NULL;
}
+
+ /*
+ * Close the write side of the pipe so epoll_wait() in
+ * lttng_consumer_thread_poll_metadata can catch it. The thread is
+ * monitoring the read side of the pipe. If we close them both, epoll_wait
+ * strangely does not return and could create a endless wait period if the
+ * pipe is the only tracked fd in the poll set. The thread will take care
+ * of closing the read side.
+ */
+ close(ctx->consumer_metadata_pipe[1]);
+ if (ret) {
+ ret = pthread_join(metadata_thread, &status);
+ if (ret < 0) {
+ PERROR("pthread_join metadata thread");
+ }
+ }
+
rcu_unregister_thread();
return NULL;
}
projects / lttng-tools.git / commitdiff
