X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fconsumer.c;h=27dfe32b8592487e6c5e881604a650085240f536;hp=0f0e60ad839a9beab57168634a8d7220a86fae62;hb=4d86847e8786d4902dceeb1dff91791112d2c396;hpb=3cc2f24a5cdabfbcb1022c0798f6b4845f72b498 diff --git a/src/common/consumer.c b/src/common/consumer.c index 0f0e60ad8..27dfe32b8 100644 --- a/src/common/consumer.c +++ b/src/common/consumer.c @@ -47,27 +47,36 @@ struct lttng_consumer_global_data consumer_data = { .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. * Also updated by the signal handler (consumer_should_exit()). Read by the * polling threads. */ -volatile int consumer_quit = 0; +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 = NULL; -struct lttng_ht *data_ht = NULL; +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 @@ -118,6 +127,12 @@ void consumer_steal_stream_key(int key, struct lttng_ht *ht) 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; @@ -129,8 +144,6 @@ static struct lttng_consumer_channel *consumer_find_channel(int key) 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); @@ -138,8 +151,6 @@ static struct lttng_consumer_channel *consumer_find_channel(int key) channel = caa_container_of(node, struct lttng_consumer_channel, node); } - rcu_read_unlock(); - return channel; } @@ -182,6 +193,17 @@ static void consumer_rcu_free_relayd(struct rcu_head *head) 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); } @@ -204,20 +226,111 @@ static void destroy_relayd(struct consumer_relayd_sock_pair *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. @@ -251,12 +364,15 @@ void consumer_del_stream(struct lttng_consumer_stream *stream, 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: @@ -281,6 +397,11 @@ void consumer_del_stream(struct lttng_consumer_stream *stream, iter.iter.node = &stream->node.node; ret = lttng_ht_del(ht, &iter); assert(!ret); + + /* Remove node session id from the consumer_data stream ht */ + iter.iter.node = &stream->node_session_id.node; + ret = lttng_ht_del(consumer_data.stream_list_ht, &iter); + assert(!ret); rcu_read_unlock(); assert(consumer_data.stream_count > 0); @@ -343,6 +464,7 @@ void consumer_del_stream(struct lttng_consumer_stream *stream, end: consumer_data.need_update = 1; + pthread_mutex_unlock(&stream->lock); pthread_mutex_unlock(&consumer_data.lock); if (free_chan) { @@ -364,6 +486,7 @@ struct lttng_consumer_stream *consumer_allocate_stream( gid_t gid, int net_index, int metadata_flag, + uint64_t session_id, int *alloc_ret) { struct lttng_consumer_stream *stream; @@ -375,6 +498,8 @@ struct lttng_consumer_stream *consumer_allocate_stream( goto end; } + rcu_read_lock(); + /* * Get stream's channel reference. Needed when adding the stream to the * global hash table. @@ -399,8 +524,10 @@ struct lttng_consumer_stream *consumer_allocate_stream( stream->gid = gid; stream->net_seq_idx = net_index; stream->metadata_flag = metadata_flag; + stream->session_id = session_id; strncpy(stream->path_name, path_name, sizeof(stream->path_name)); stream->path_name[sizeof(stream->path_name) - 1] = '\0'; + pthread_mutex_init(&stream->lock, NULL); /* * Index differently the metadata node because the thread is using an @@ -413,6 +540,9 @@ struct lttng_consumer_stream *consumer_allocate_stream( lttng_ht_node_init_ulong(&stream->node, stream->key); } + /* Init session id node with the stream session id */ + lttng_ht_node_init_ulong(&stream->node_session_id, stream->session_id); + /* * The cpu number is needed before using any ustctl_* actions. Ignored for * the kernel so the value does not matter. @@ -422,13 +552,16 @@ struct lttng_consumer_stream *consumer_allocate_stream( pthread_mutex_unlock(&consumer_data.lock); DBG3("Allocated stream %s (key %d, shm_fd %d, wait_fd %d, mmap_len %llu," - " out_fd %d, net_seq_idx %d)", stream->path_name, stream->key, - stream->shm_fd, stream->wait_fd, + " out_fd %d, net_seq_idx %d, session_id %" PRIu64, + 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->net_seq_idx, stream->session_id); + + rcu_read_unlock(); return stream; error: + rcu_read_unlock(); free(stream); end: return NULL; @@ -449,6 +582,7 @@ static int consumer_add_stream(struct lttng_consumer_stream *stream, 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 */ @@ -456,6 +590,13 @@ static int consumer_add_stream(struct lttng_consumer_stream *stream, lttng_ht_add_unique_ulong(ht, &stream->node); + /* + * Add stream to the stream_list_ht of the consumer data. No need to steal + * the key since the HT does not use it and we allow to add redundant keys + * into this table. + */ + lttng_ht_add_ulong(consumer_data.stream_list_ht, &stream->node_session_id); + /* Check and cleanup relayd */ relayd = consumer_find_relayd(stream->net_seq_idx); if (relayd != NULL) { @@ -481,6 +622,7 @@ static int consumer_add_stream(struct lttng_consumer_stream *stream, consumer_data.need_update = 1; rcu_read_unlock(); + pthread_mutex_unlock(&stream->lock); pthread_mutex_unlock(&consumer_data.lock); return ret; @@ -606,6 +748,13 @@ static int write_relayd_stream_header(struct lttng_consumer_stream *stream, data_hdr.stream_id = htobe64(stream->relayd_stream_id); data_hdr.data_size = htobe32(data_size); data_hdr.padding_size = htobe32(padding); + /* + * Note that net_seq_num below is assigned with the *current* value of + * next_net_seq_num and only after that the next_net_seq_num will be + * increment. This is why when issuing a command on the relayd using + * this next value, 1 should always be substracted in order to compare + * the last seen sequence number on the relayd side to the last sent. + */ data_hdr.net_seq_num = htobe64(stream->next_net_seq_num++); /* Other fields are zeroed previously */ @@ -643,6 +792,8 @@ void consumer_del_channel(struct lttng_consumer_channel *channel) 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) { @@ -786,7 +937,17 @@ static int consumer_update_poll_array( 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); @@ -870,8 +1031,8 @@ int lttng_consumer_send_error( } /* - * 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) { @@ -890,6 +1051,15 @@ 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); } /* @@ -902,9 +1072,11 @@ void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx) do { ret = write(ctx->consumer_should_quit[1], "4", 1); } while (ret < 0 && errno == EINTR); - if (ret < 0) { + if (ret < 0 || ret != 1) { PERROR("write consumer quit"); } + + DBG("Consumer flag that it should quit"); } void lttng_consumer_sync_trace_file(struct lttng_consumer_stream *stream, @@ -1066,6 +1238,8 @@ void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx) { int ret; + DBG("Consumer destroying it. Closing everything."); + ret = close(ctx->consumer_error_socket); if (ret) { PERROR("close"); @@ -1116,8 +1290,22 @@ static int write_relayd_metadata_id(int fd, do { ret = write(fd, (void *) &hdr, sizeof(hdr)); } while (ret < 0 && errno == EINTR); - if (ret < 0) { - PERROR("write metadata stream id"); + if (ret < 0 || ret != sizeof(hdr)) { + /* + * This error means that the fd's end is closed so ignore the perror + * not to clubber the error output since this can happen in a normal + * code path. + */ + if (errno != EPIPE) { + PERROR("write metadata stream id"); + } + DBG3("Consumer failed to write relayd metadata id (errno: %d)", errno); + /* + * Set ret to a negative value because if ret != sizeof(hdr), we don't + * handle writting the missing part so report that as an error and + * don't lie to the caller. + */ + ret = -1; goto end; } DBG("Metadata stream id %" PRIu64 " with padding %lu written before data", @@ -1132,6 +1320,8 @@ end: * 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 @@ -1147,6 +1337,7 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap( /* 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(); @@ -1204,11 +1395,22 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap( 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; @@ -1220,10 +1422,21 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap( } while (ret < 0 && errno == EINTR); DBG("Consumer mmap write() ret %zd (len %lu)", ret, len); if (ret < 0) { - PERROR("Error in file write"); + /* + * This is possible if the fd is closed on the other side (outfd) + * or any write problem. It can be verbose a bit for a normal + * execution if for instance the relayd is stopped abruptly. This + * can happen so set this to a DBG statement. + */ + DBG("Error in file write mmap"); 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); @@ -1245,6 +1458,15 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap( } 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) { @@ -1258,6 +1480,8 @@ end: /* * 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( @@ -1273,6 +1497,7 @@ 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: @@ -1323,6 +1548,12 @@ ssize_t lttng_consumer_on_read_subbuffer_splice( 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; } @@ -1334,7 +1565,12 @@ ssize_t lttng_consumer_on_read_subbuffer_splice( /* 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 { @@ -1383,6 +1619,12 @@ ssize_t lttng_consumer_on_read_subbuffer_splice( 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) { @@ -1410,12 +1652,20 @@ ssize_t lttng_consumer_on_read_subbuffer_splice( 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; @@ -1504,7 +1754,6 @@ int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx, */ static void destroy_data_stream_ht(struct lttng_ht *ht) { - int ret; struct lttng_ht_iter iter; struct lttng_consumer_stream *stream; @@ -1514,10 +1763,11 @@ static void destroy_data_stream_ht(struct lttng_ht *ht) 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(); @@ -1531,7 +1781,6 @@ static void destroy_data_stream_ht(struct lttng_ht *ht) */ static void destroy_stream_ht(struct lttng_ht *ht) { - int ret; struct lttng_ht_iter iter; struct lttng_consumer_stream *stream; @@ -1541,10 +1790,11 @@ static void destroy_stream_ht(struct lttng_ht *ht) 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(); @@ -1577,6 +1827,8 @@ void consumer_del_metadata_stream(struct lttng_consumer_stream *stream, } pthread_mutex_lock(&consumer_data.lock); + pthread_mutex_lock(&stream->lock); + switch (consumer_data.type) { case LTTNG_CONSUMER_KERNEL: if (stream->mmap_base != NULL) { @@ -1600,6 +1852,11 @@ void consumer_del_metadata_stream(struct lttng_consumer_stream *stream, iter.iter.node = &stream->node.node; ret = lttng_ht_del(ht, &iter); assert(!ret); + + /* Remove node session id from the consumer_data stream ht */ + iter.iter.node = &stream->node_session_id.node; + ret = lttng_ht_del(consumer_data.stream_list_ht, &iter); + assert(!ret); rcu_read_unlock(); if (stream->out_fd >= 0) { @@ -1661,6 +1918,7 @@ void consumer_del_metadata_stream(struct lttng_consumer_stream *stream, } end: + pthread_mutex_unlock(&stream->lock); pthread_mutex_unlock(&consumer_data.lock); if (free_chan) { @@ -1680,6 +1938,8 @@ static int consumer_add_metadata_stream(struct lttng_consumer_stream *stream, { int ret = 0; struct consumer_relayd_sock_pair *relayd; + struct lttng_ht_iter iter; + struct lttng_ht_node_ulong *node; assert(stream); assert(ht); @@ -1687,6 +1947,7 @@ static int consumer_add_metadata_stream(struct lttng_consumer_stream *stream, 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 @@ -1694,6 +1955,15 @@ static int consumer_add_metadata_stream(struct lttng_consumer_stream *stream, */ 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) { @@ -1714,16 +1984,75 @@ static int consumer_add_metadata_stream(struct lttng_consumer_stream *stream, 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); + + /* + * Add stream to the stream_list_ht of the consumer data. No need to steal + * the key since the HT does not use it and we allow to add redundant keys + * into this table. + */ + lttng_ht_add_ulong(consumer_data.stream_list_ht, &stream->node_session_id); + 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. @@ -1741,6 +2070,12 @@ void *consumer_thread_metadata_poll(void *data) 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 */ @@ -1759,17 +2094,13 @@ void *consumer_thread_metadata_poll(void *data) 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) { + if (LTTNG_POLL_GETNB(&events) == 0 && consumer_quit == 1) { goto end; } restart: - DBG("Metadata poll wait with %d fd(s)", nb_fd); + DBG("Metadata poll wait with %d fd(s)", LTTNG_POLL_GETNB(&events)); ret = lttng_poll_wait(&events, -1); DBG("Metadata event catched in thread"); if (ret < 0) { @@ -1780,6 +2111,8 @@ restart: goto error; } + nb_fd = ret; + /* From here, the event is a metadata wait fd */ for (i = 0; i < nb_fd; i++) { revents = LTTNG_POLL_GETEV(&events, i); @@ -1798,7 +2131,10 @@ restart: * 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 { @@ -1815,6 +2151,13 @@ restart: 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); @@ -1879,8 +2222,9 @@ restart: len = ctx->on_buffer_ready(stream, ctx); /* It's ok to have an unavailable sub-buffer */ if (len < 0 && len != -EAGAIN && len != -ENODATA) { - rcu_read_unlock(); - goto end; + /* Clean up stream from consumer and free it. */ + lttng_poll_del(&events, stream->wait_fd); + consumer_del_metadata_stream(stream, metadata_ht); } else if (len > 0) { stream->data_read = 1; } @@ -1896,9 +2240,7 @@ end: 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; @@ -1923,6 +2265,7 @@ void *consumer_thread_data_poll(void *data) data_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); if (data_ht == NULL) { + /* ENOMEM at this point. Better to bail out. */ goto end; } @@ -1983,7 +2326,7 @@ void *consumer_thread_data_poll(void *data) /* 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) { /* @@ -2014,6 +2357,11 @@ void *consumer_thread_data_poll(void *data) pipe_readlen = read(ctx->consumer_data_pipe[0], &new_stream, sizeof(new_stream)); } while (pipe_readlen == -1 && errno == EINTR); + if (pipe_readlen < 0) { + PERROR("read consumer data pipe"); + /* Continue so we can at least handle the current stream(s). */ + continue; + } /* * If the stream is NULL, just ignore it. It's also possible that @@ -2021,6 +2369,7 @@ void *consumer_thread_data_poll(void *data) * waking us up to test it. */ if (new_stream == NULL) { + validate_endpoint_status_data_stream(); continue; } @@ -2041,13 +2390,18 @@ void *consumer_thread_data_poll(void *data) /* 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; len = ctx->on_buffer_ready(local_stream[i], ctx); /* it's ok to have an unavailable sub-buffer */ if (len < 0 && len != -EAGAIN && len != -ENODATA) { - goto end; + /* 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; } @@ -2064,13 +2418,18 @@ void *consumer_thread_data_poll(void *data) /* 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); len = ctx->on_buffer_ready(local_stream[i], ctx); /* it's ok to have an unavailable sub-buffer */ if (len < 0 && len != -EAGAIN && len != -ENODATA) { - goto end; + /* 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; } @@ -2079,12 +2438,15 @@ void *consumer_thread_data_poll(void *data) /* 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; @@ -2098,22 +2460,27 @@ void *consumer_thread_data_poll(void *data) 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: @@ -2135,12 +2502,13 @@ 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; } @@ -2151,7 +2519,7 @@ end: */ 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. @@ -2201,7 +2569,7 @@ void *consumer_thread_sessiond_poll(void *data) /* Blocking call, waiting for transmission */ sock = lttcomm_accept_unix_sock(client_socket); - if (sock <= 0) { + if (sock < 0) { WARN("On accept"); goto end; } @@ -2211,6 +2579,13 @@ void *consumer_thread_sessiond_poll(void *data) 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; @@ -2248,23 +2623,25 @@ end: */ 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; @@ -2273,17 +2650,27 @@ end: 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) @@ -2308,11 +2695,7 @@ void lttng_consumer_init(void) { consumer_data.channel_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); consumer_data.relayd_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); + consumer_data.stream_list_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); } /* @@ -2323,13 +2706,22 @@ void lttng_consumer_init(void) */ int consumer_add_relayd_socket(int net_seq_idx, int sock_type, struct lttng_consumer_local_data *ctx, int sock, - struct pollfd *consumer_sockpoll, struct lttcomm_sock *relayd_sock) + struct pollfd *consumer_sockpoll, struct lttcomm_sock *relayd_sock, + unsigned int sessiond_id) { - int fd, ret = -1; + int fd = -1, ret = -1, relayd_created = 0; + enum lttng_error_code ret_code = LTTNG_OK; struct consumer_relayd_sock_pair *relayd; DBG("Consumer adding relayd socket (idx: %d)", net_seq_idx); + /* First send a status message before receiving the fds. */ + ret = consumer_send_status_msg(sock, ret_code); + if (ret < 0) { + /* Somehow, the session daemon is not responding anymore. */ + goto error; + } + /* Get relayd reference if exists. */ relayd = consumer_find_relayd(net_seq_idx); if (relayd == NULL) { @@ -2337,8 +2729,11 @@ int consumer_add_relayd_socket(int net_seq_idx, int sock_type, relayd = consumer_allocate_relayd_sock_pair(net_seq_idx); if (relayd == NULL) { lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); + ret = -1; goto error; } + relayd->sessiond_session_id = (uint64_t) sessiond_id; + relayd_created = 1; } /* Poll on consumer socket. */ @@ -2352,6 +2747,14 @@ int consumer_add_relayd_socket(int net_seq_idx, int sock_type, 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; + } + + /* We have the fds without error. Send status back. */ + ret = consumer_send_status_msg(sock, ret_code); + if (ret < 0) { + /* Somehow, the session daemon is not responding anymore. */ goto error; } @@ -2361,32 +2764,58 @@ int consumer_add_relayd_socket(int net_seq_idx, int sock_type, /* 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; + + /* + * Create a session on the relayd and store the returned id. Lock the + * control socket mutex if the relayd was NOT created before. + */ + if (!relayd_created) { + pthread_mutex_lock(&relayd->ctrl_sock_mutex); + } + ret = relayd_create_session(&relayd->control_sock, + &relayd->relayd_session_id); + if (!relayd_created) { + pthread_mutex_unlock(&relayd->ctrl_sock_mutex); + } + if (ret < 0) { + goto error; + } + break; case LTTNG_STREAM_DATA: /* 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; default: ERR("Unknown relayd socket type (%d)", sock_type); + ret = -1; goto error; } @@ -2401,8 +2830,224 @@ int consumer_add_relayd_socket(int net_seq_idx, int sock_type, 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"); + } + } + + if (relayd_created) { + /* We just want to cleanup. Ignore ret value. */ + (void) relayd_close(&relayd->control_sock); + (void) relayd_close(&relayd->data_sock); + free(relayd); + } + 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; +} + +/* + * Search for a relayd associated to the session id and return the reference. + * + * A rcu read side lock MUST be acquire before calling this function and locked + * until the relayd object is no longer necessary. + */ +static struct consumer_relayd_sock_pair *find_relayd_by_session_id(uint64_t id) +{ + struct lttng_ht_iter iter; + struct consumer_relayd_sock_pair *relayd = NULL; + + /* Iterate over all relayd since they are indexed by net_seq_idx. */ + cds_lfht_for_each_entry(consumer_data.relayd_ht->ht, &iter.iter, relayd, + node.node) { + /* + * Check by sessiond id which is unique here where the relayd session + * id might not be when having multiple relayd. + */ + if (relayd->sessiond_session_id == id) { + /* Found the relayd. There can be only one per id. */ + goto found; + } + } + + return NULL; + +found: + return relayd; +} + +/* + * Check if for a given session id there is still data needed to be extract + * from the buffers. + * + * Return 1 if data is pending or else 0 meaning ready to be read. + */ +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 = NULL; + int (*data_pending)(struct lttng_consumer_stream *); + + 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_pending = lttng_kconsumer_data_pending; + break; + case LTTNG_CONSUMER32_UST: + case LTTNG_CONSUMER64_UST: + data_pending = lttng_ustconsumer_data_pending; + break; + default: + ERR("Unknown consumer data type"); + assert(0); + } + + /* 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. */ + goto data_not_pending; + } + } + + cds_lfht_for_each_entry_duplicate(ht->ht, + ht->hash_fct((void *)((unsigned long) id), lttng_ht_seed), + ht->match_fct, (void *)((unsigned long) 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; + } + + /* + * 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_pending; + } + } + + /* Relayd check */ + if (relayd) { + pthread_mutex_lock(&relayd->ctrl_sock_mutex); + if (stream->metadata_flag) { + ret = relayd_quiescent_control(&relayd->control_sock, + stream->relayd_stream_id); + } else { + ret = relayd_data_pending(&relayd->control_sock, + stream->relayd_stream_id, + stream->next_net_seq_num - 1); + } + 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); + ret = relayd_end_data_pending(&relayd->control_sock, + relayd->relayd_session_id, &is_data_inflight); + pthread_mutex_unlock(&relayd->ctrl_sock_mutex); + if (ret < 0) { + goto data_not_pending; + } + if (is_data_inflight) { + goto data_pending; + } + } + + /* + * Finding _no_ node in the hash table and no inflight data means that the + * stream(s) have been removed thus data is guaranteed to be available for + * analysis from the trace files. + */ + +data_not_pending: + /* Data is available to be read by a viewer. */ + pthread_mutex_unlock(&consumer_data.lock); + rcu_read_unlock(); + return 0; + +data_pending: + /* Data is still being extracted from buffers. */ + pthread_mutex_unlock(&consumer_data.lock); + rcu_read_unlock(); + return 1; +} + +/* + * Send a ret code status message to the sessiond daemon. + * + * Return the sendmsg() return value. + */ +int consumer_send_status_msg(int sock, int ret_code) +{ + struct lttcomm_consumer_status_msg msg; + + msg.ret_code = ret_code; + + return lttcomm_send_unix_sock(sock, &msg, sizeof(msg)); +}