#define _GNU_SOURCE
#include <assert.h>
+#include <lttng/ust-ctl.h>
#include <poll.h>
#include <pthread.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
+#include <inttypes.h>
#include <unistd.h>
-#include <lttng/ust-ctl.h>
#include <common/common.h>
#include <common/sessiond-comm/sessiond-comm.h>
extern volatile int consumer_quit;
/*
- * Mmap the ring buffer, read it and write the data to the tracefile.
- *
- * Returns the number of bytes written, else negative value on error.
- */
-ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
- struct lttng_consumer_local_data *ctx,
- struct lttng_consumer_stream *stream, unsigned long len)
-{
- unsigned long mmap_offset;
- long ret = 0, written = 0;
- off_t orig_offset = stream->out_fd_offset;
- int outfd = stream->out_fd;
- uint64_t metadata_id;
- struct consumer_relayd_sock_pair *relayd = NULL;
-
- /* Flag that the current stream if set for network streaming. */
- if (stream->net_seq_idx != -1) {
- relayd = consumer_find_relayd(stream->net_seq_idx);
- if (relayd == NULL) {
- goto end;
- }
- }
-
- /* get the offset inside the fd to mmap */
- ret = ustctl_get_mmap_read_offset(stream->chan->handle,
- stream->buf, &mmap_offset);
- if (ret != 0) {
- errno = -ret;
- PERROR("ustctl_get_mmap_read_offset");
- written = ret;
- goto end;
- }
-
- /* Handle stream on the relayd if the output is on the network */
- if (relayd) {
- if (stream->metadata_flag) {
- /* Only lock if metadata since we use the control socket. */
- pthread_mutex_lock(&relayd->ctrl_sock_mutex);
- }
-
- ret = consumer_handle_stream_before_relayd(stream, len);
- if (ret >= 0) {
- outfd = ret;
-
- /* Write metadata stream id before payload */
- if (stream->metadata_flag) {
- metadata_id = htobe64(stream->relayd_stream_id);
- do {
- ret = write(outfd, (void *) &metadata_id,
- sizeof(stream->relayd_stream_id));
- if (ret < 0) {
- PERROR("write metadata stream id");
- written = ret;
- goto end;
- }
- } while (errno == EINTR);
- DBG("Metadata stream id %zu written before data",
- stream->relayd_stream_id);
- }
- }
- /* Else, use the default set before which is the filesystem. */
- }
-
- while (len > 0) {
- ret = write(outfd, stream->mmap_base + mmap_offset, len);
- if (ret < 0) {
- if (errno == EINTR) {
- /* restart the interrupted system call */
- continue;
- } else {
- PERROR("Error in file write");
- if (written == 0) {
- written = ret;
- }
- goto end;
- }
- } else if (ret > len) {
- PERROR("ret %ld > len %lu", ret, len);
- written += ret;
- goto end;
- } else {
- len -= ret;
- mmap_offset += ret;
- }
- DBG("UST mmap write() ret %ld (len %lu)", ret, len);
-
- /* 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, ret,
- SYNC_FILE_RANGE_WRITE);
- stream->out_fd_offset += ret;
- }
- written += ret;
- }
- lttng_consumer_sync_trace_file(stream, orig_offset);
-
-end:
- if (relayd && stream->metadata_flag) {
- pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
- }
- return written;
-}
-
-/*
- * Splice the data from the ring buffer to the tracefile.
- *
- * Returns the number of bytes spliced.
+ * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
+ * compiled out, we isolate it in this library.
*/
-ssize_t lttng_ustconsumer_on_read_subbuffer_splice(
- struct lttng_consumer_local_data *ctx,
- struct lttng_consumer_stream *stream, unsigned long len)
+int lttng_ustctl_get_mmap_read_offset(struct lttng_ust_shm_handle *handle,
+ struct lttng_ust_lib_ring_buffer *buf, unsigned long *off)
{
- return -ENOSYS;
-}
+ return ustctl_get_mmap_read_offset(handle, buf, off);
+};
/*
* Take a snapshot for a specific fd
return ret;
}
+/*
+ * Receive command from session daemon and process it.
+ *
+ * Return 1 on success else a negative value or 0.
+ */
int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
int sock, struct pollfd *consumer_sockpoll)
{
ssize_t ret;
+ enum lttng_error_code ret_code = LTTNG_OK;
struct lttcomm_consumer_msg msg;
ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg));
if (ret != sizeof(msg)) {
- lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
+ DBG("Consumer received unexpected message size %zd (expects %zu)",
+ ret, sizeof(msg));
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD);
return ret;
}
if (msg.cmd_type == LTTNG_CONSUMER_STOP) {
+ /*
+ * Notify the session daemon that the command is completed.
+ *
+ * On transport layer error, the function call will print an error
+ * message so handling the returned code is a bit useless since we
+ * return an error code anyway.
+ */
+ (void) consumer_send_status_msg(sock, ret_code);
return -ENOENT;
}
+ /* relayd needs RCU read-side lock */
+ rcu_read_lock();
+
switch (msg.cmd_type) {
case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
{
- int fd;
- struct consumer_relayd_sock_pair *relayd;
-
- DBG("UST Consumer adding relayd socket");
-
- /* Get relayd reference if exists. */
- relayd = consumer_find_relayd(msg.u.relayd_sock.net_index);
- if (relayd == NULL) {
- /* Not found. Allocate one. */
- relayd = consumer_allocate_relayd_sock_pair(
- msg.u.relayd_sock.net_index);
- if (relayd == NULL) {
- lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR);
- goto end_nosignal;
- }
- }
-
- /* Poll on consumer socket. */
- if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
- return -EINTR;
- }
-
- /* Get relayd socket from session daemon */
- ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
- if (ret != sizeof(fd)) {
- lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
- goto end_nosignal;
- }
-
- /* Copy socket information and received FD */
- switch (msg.u.relayd_sock.type) {
- case LTTNG_STREAM_CONTROL:
- /* Copy received lttcomm socket */
- lttcomm_copy_sock(&relayd->control_sock, &msg.u.relayd_sock.sock);
- ret = lttcomm_create_sock(&relayd->control_sock);
- if (ret < 0) {
- goto end_nosignal;
- }
-
- /* Close the created socket fd which is useless */
- close(relayd->control_sock.fd);
-
- /* Assign new file descriptor */
- relayd->control_sock.fd = fd;
- break;
- case LTTNG_STREAM_DATA:
- /* Copy received lttcomm socket */
- lttcomm_copy_sock(&relayd->data_sock, &msg.u.relayd_sock.sock);
- ret = lttcomm_create_sock(&relayd->data_sock);
- if (ret < 0) {
- goto end_nosignal;
- }
-
- /* 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");
- goto end_nosignal;
- }
-
- DBG("Consumer %s socket created successfully with net idx %d (fd: %d)",
- msg.u.relayd_sock.type == LTTNG_STREAM_CONTROL ? "control" : "data",
- relayd->net_seq_idx, fd);
-
- /*
- * Add relayd socket pair to consumer data hashtable. If object already
- * exists or on error, the function gracefully returns.
- */
- consumer_add_relayd(relayd);
-
+ /* Session daemon status message are handled in the following call. */
+ ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index,
+ msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll,
+ &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id);
goto end_nosignal;
}
case LTTNG_CONSUMER_ADD_CHANNEL:
int fds[1];
size_t nb_fd = 1;
+ DBG("UST Consumer adding channel");
+
+ /* 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 end_nosignal;
+ }
+
/* block */
if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
+ rcu_read_unlock();
return -EINTR;
}
ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd);
if (ret != sizeof(fds)) {
- lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD);
+ rcu_read_unlock();
return ret;
}
+ /*
+ * Send status code to session daemon only if the recv works. If the
+ * above recv() failed, the session daemon is notified through the
+ * error socket and the teardown is eventually done.
+ */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+
DBG("consumer_add_channel %d", msg.u.channel.channel_key);
new_channel = consumer_allocate_channel(msg.u.channel.channel_key,
fds[0], -1,
msg.u.channel.mmap_len,
- msg.u.channel.max_sb_size);
+ msg.u.channel.max_sb_size,
+ msg.u.channel.nb_init_streams);
if (new_channel == NULL) {
- lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR);
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
goto end_nosignal;
}
if (ctx->on_recv_channel != NULL) {
case LTTNG_CONSUMER_ADD_STREAM:
{
struct lttng_consumer_stream *new_stream;
- int fds[2];
+ int fds[2], stream_pipe;
size_t nb_fd = 2;
struct consumer_relayd_sock_pair *relayd = NULL;
+ int alloc_ret = 0;
+
+ DBG("UST Consumer adding stream");
+
+ /* 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 end_nosignal;
+ }
/* block */
if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
+ rcu_read_unlock();
return -EINTR;
}
ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd);
if (ret != sizeof(fds)) {
- lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD);
+ rcu_read_unlock();
return ret;
}
+ /*
+ * Send status code to session daemon only if the recv works. If the
+ * above recv() failed, the session daemon is notified through the
+ * error socket and the teardown is eventually done.
+ */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+
+ DBG("Consumer command ADD_STREAM chan %d stream %d",
+ msg.u.stream.channel_key, msg.u.stream.stream_key);
+
assert(msg.u.stream.output == LTTNG_EVENT_MMAP);
- new_stream = consumer_allocate_stream(msg.u.channel.channel_key,
+ new_stream = consumer_allocate_stream(msg.u.stream.channel_key,
msg.u.stream.stream_key,
fds[0], fds[1],
msg.u.stream.state,
msg.u.stream.uid,
msg.u.stream.gid,
msg.u.stream.net_index,
- msg.u.stream.metadata_flag);
+ msg.u.stream.metadata_flag,
+ msg.u.stream.session_id,
+ &alloc_ret);
if (new_stream == NULL) {
- lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR);
- goto end;
+ switch (alloc_ret) {
+ case -ENOMEM:
+ case -EINVAL:
+ default:
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
+ break;
+ case -ENOENT:
+ /*
+ * We could not find the channel. Can happen if cpu hotplug
+ * happens while tearing down.
+ */
+ DBG3("Could not find channel");
+ break;
+ }
+ goto end_nosignal;
}
/* The stream is not metadata. Get relayd reference if exists. */
&new_stream->relayd_stream_id);
pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
if (ret < 0) {
- goto end;
+ consumer_del_stream(new_stream, NULL);
+ goto end_nosignal;
}
} else if (msg.u.stream.net_index != -1) {
ERR("Network sequence index %d unknown. Not adding stream.",
msg.u.stream.net_index);
- free(new_stream);
- goto end;
+ consumer_del_stream(new_stream, NULL);
+ goto end_nosignal;
}
- if (ctx->on_recv_stream != NULL) {
+ /* Do actions once stream has been received. */
+ if (ctx->on_recv_stream) {
ret = ctx->on_recv_stream(new_stream);
- if (ret == 0) {
- consumer_add_stream(new_stream);
- } else if (ret < 0) {
- goto end;
+ if (ret < 0) {
+ consumer_del_stream(new_stream, NULL);
+ goto end_nosignal;
}
+ }
+
+ /* Get the right pipe where the stream will be sent. */
+ if (new_stream->metadata_flag) {
+ stream_pipe = ctx->consumer_metadata_pipe[1];
} else {
- consumer_add_stream(new_stream);
+ stream_pipe = ctx->consumer_data_pipe[1];
}
- DBG("UST consumer_add_stream %s (%d,%d) with relayd id %lu",
+ do {
+ ret = write(stream_pipe, &new_stream, sizeof(new_stream));
+ } while (ret < 0 && errno == EINTR);
+ if (ret < 0) {
+ PERROR("Consumer write %s stream to pipe %d",
+ new_stream->metadata_flag ? "metadata" : "data",
+ stream_pipe);
+ consumer_del_stream(new_stream, NULL);
+ goto end_nosignal;
+ }
+
+ DBG("UST consumer ADD_STREAM %s (%d,%d) with relayd id %" PRIu64,
msg.u.stream.path_name, fds[0], fds[1],
new_stream->relayd_stream_id);
break;
}
+ case LTTNG_CONSUMER_DESTROY_RELAYD:
+ {
+ uint64_t index = msg.u.destroy_relayd.net_seq_idx;
+ struct consumer_relayd_sock_pair *relayd;
+
+ DBG("UST consumer destroying relayd %" PRIu64, index);
+
+ /* Get relayd reference if exists. */
+ relayd = consumer_find_relayd(index);
+ if (relayd == NULL) {
+ ERR("Unable to find relayd %" PRIu64, index);
+ ret_code = LTTNG_ERR_NO_CONSUMER;
+ }
+
+ /*
+ * Each relayd socket pair has a refcount of stream attached to it
+ * which tells if the relayd is still active or not depending on the
+ * refcount value.
+ *
+ * This will set the destroy flag of the relayd object and destroy it
+ * if the refcount reaches zero when called.
+ *
+ * The destroy can happen either here or when a stream fd hangs up.
+ */
+ if (relayd) {
+ consumer_flag_relayd_for_destroy(relayd);
+ }
+
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+
+ goto end_nosignal;
+ }
case LTTNG_CONSUMER_UPDATE_STREAM:
{
+ rcu_read_unlock();
return -ENOSYS;
-#if 0
- if (ctx->on_update_stream != NULL) {
- ret = ctx->on_update_stream(msg.u.stream.stream_key, msg.u.stream.state);
- if (ret == 0) {
- consumer_change_stream_state(msg.u.stream.stream_key, msg.u.stream.state);
- } else if (ret < 0) {
- goto end;
- }
- } else {
- consumer_change_stream_state(msg.u.stream.stream_key,
- msg.u.stream.state);
+ }
+ case LTTNG_CONSUMER_DATA_PENDING:
+ {
+ int32_t ret;
+ uint64_t id = msg.u.data_pending.session_id;
+
+ DBG("UST consumer data pending command for id %" PRIu64, id);
+
+ ret = consumer_data_pending(id);
+
+ /* Send back returned value to session daemon */
+ ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret));
+ if (ret < 0) {
+ PERROR("send data pending ret code");
}
-#endif
+
+ /*
+ * No need to send back a status message since the data pending
+ * returned value is the response.
+ */
break;
}
default:
break;
}
-end:
+
+end_nosignal:
+ rcu_read_unlock();
+
/*
- * Wake-up the other end by writing a null byte in the pipe
- * (non-blocking). Important note: Because writing into the
- * pipe is non-blocking (and therefore we allow dropping wakeup
- * data, as long as there is wakeup data present in the pipe
- * buffer to wake up the other end), the other end should
- * perform the following sequence for waiting:
- * 1) empty the pipe (reads).
- * 2) perform update operation.
- * 3) wait on the pipe (poll).
+ * Return 1 to indicate success since the 0 value can be a socket
+ * shutdown during the recv() or send() call.
*/
- do {
- ret = write(ctx->consumer_poll_pipe[1], "", 1);
- } while (ret == -1UL && errno == EINTR);
-end_nosignal:
- return 0;
+ return 1;
}
int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel *chan)
ustctl_unmap_channel(chan->handle);
}
-int lttng_ustconsumer_allocate_stream(struct lttng_consumer_stream *stream)
+int lttng_ustconsumer_add_stream(struct lttng_consumer_stream *stream)
{
struct lttng_ust_object_data obj;
int ret;
obj.wait_fd = stream->wait_fd;
obj.memory_map_size = stream->mmap_len;
ret = ustctl_add_stream(stream->chan->handle, &obj);
- if (ret)
- return ret;
+ if (ret) {
+ ERR("UST ctl add_stream failed with ret %d", ret);
+ goto error;
+ }
+
stream->buf = ustctl_open_stream_read(stream->chan->handle, stream->cpu);
- if (!stream->buf)
- return -EBUSY;
+ if (!stream->buf) {
+ ERR("UST ctl open_stream_read failed");
+ ret = -EBUSY;
+ goto error;
+ }
+
/* ustctl_open_stream_read has closed the shm fd. */
stream->wait_fd_is_copy = 1;
stream->shm_fd = -1;
stream->mmap_base = ustctl_get_mmap_base(stream->chan->handle, stream->buf);
if (!stream->mmap_base) {
- return -EINVAL;
+ ERR("UST ctl get_mmap_base failed");
+ ret = -EINVAL;
+ goto mmap_error;
}
return 0;
+
+mmap_error:
+ ustctl_close_stream_read(stream->chan->handle, stream->buf);
+error:
+ return ret;
}
void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream)
int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
struct lttng_consumer_local_data *ctx)
{
- unsigned long len;
+ unsigned long len, subbuf_size, padding;
int err;
long ret = 0;
struct lttng_ust_shm_handle *handle;
struct lttng_ust_lib_ring_buffer *buf;
char dummy;
- ssize_t readlen;
DBG("In read_subbuffer (wait_fd: %d, stream key: %d)",
stream->wait_fd, stream->key);
/* We can consume the 1 byte written into the wait_fd by UST */
if (!stream->hangup_flush_done) {
+ ssize_t readlen;
+
do {
readlen = read(stream->wait_fd, &dummy, 1);
} while (readlen == -1 && errno == EINTR);
/* Get the next subbuffer */
err = ustctl_get_next_subbuf(handle, buf);
if (err != 0) {
- ret = -ret; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
+ ret = err; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
/*
* This is a debug message even for single-threaded consumer,
* because poll() have more relaxed criterions than get subbuf,
goto end;
}
assert(stream->output == LTTNG_EVENT_MMAP);
- /* read the used subbuffer size */
+ /* Get the full padded subbuffer size */
err = ustctl_get_padded_subbuf_size(handle, buf, &len);
assert(err == 0);
+
+ /* Get subbuffer data size (without padding) */
+ err = ustctl_get_subbuf_size(handle, buf, &subbuf_size);
+ assert(err == 0);
+
+ /* Make sure we don't get a subbuffer size bigger than the padded */
+ assert(len >= subbuf_size);
+
+ padding = len - subbuf_size;
/* write the subbuffer to the tracefile */
- ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len);
- if (ret != len) {
+ ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size, padding);
+ /*
+ * The mmap operation should write subbuf_size amount of data when network
+ * streaming or the full padding (len) size when we are _not_ streaming.
+ */
+ if ((ret != subbuf_size && stream->net_seq_idx != -1) ||
+ (ret != len && stream->net_seq_idx == -1)) {
/*
- * display the error but continue processing to try
- * to release the subbuffer
+ * Display the error but continue processing to try to release the
+ * subbuffer
*/
- ERR("Error writing to tracefile");
+ ERR("Error writing to tracefile "
+ "(ret: %zd != len: %lu != subbuf_size: %lu)",
+ ret, len, subbuf_size);
}
err = ustctl_put_next_subbuf(handle, buf);
assert(err == 0);
stream->out_fd = ret;
}
+ ret = lttng_ustconsumer_add_stream(stream);
+ if (ret) {
+ consumer_del_stream(stream, NULL);
+ ret = -1;
+ goto error;
+ }
+
/* we return 0 to let the library handle the FD internally */
return 0;
error:
return ret;
}
+
+/*
+ * Check if data is still being extracted from the buffers for a specific
+ * stream. Consumer data lock MUST be acquired before calling this function
+ * and the stream lock.
+ *
+ * Return 1 if the traced data are still getting read else 0 meaning that the
+ * data is available for trace viewer reading.
+ */
+int lttng_ustconsumer_data_pending(struct lttng_consumer_stream *stream)
+{
+ int ret;
+
+ assert(stream);
+
+ DBG("UST consumer checking data pending");
+
+ ret = ustctl_get_next_subbuf(stream->chan->handle, stream->buf);
+ if (ret == 0) {
+ /* There is still data so let's put back this subbuffer. */
+ ret = ustctl_put_subbuf(stream->chan->handle, stream->buf);
+ assert(ret == 0);
+ ret = 1; /* Data is pending */
+ goto end;
+ }
+
+ /* Data is NOT pending so ready to be read. */
+ ret = 0;
+
+end:
+ return ret;
+}