#include <common/utils.h>
#include <common/index/index.h>
#include <common/consumer/consumer.h>
+#include <common/shm.h>
+#include <common/optional.h>
#include "ust-consumer.h"
lttng_ustconsumer_del_channel(channel);
lttng_ustconsumer_free_channel(channel);
}
+
+ if (channel->trace_chunk) {
+ lttng_trace_chunk_put(channel->trace_chunk);
+ }
+
free(channel);
}
return ret;
}
-/*
- * create_posix_shm is never called concurrently within a process.
- */
-static
-int create_posix_shm(void)
-{
- char tmp_name[NAME_MAX];
- int shmfd, ret;
-
- ret = snprintf(tmp_name, NAME_MAX, "/ust-shm-consumer-%d", getpid());
- if (ret < 0) {
- PERROR("snprintf");
- return -1;
- }
- /*
- * Allocate shm, and immediately unlink its shm oject, keeping
- * only the file descriptor as a reference to the object.
- * We specifically do _not_ use the / at the beginning of the
- * pathname so that some OS implementations can keep it local to
- * the process (POSIX leaves this implementation-defined).
- */
- shmfd = shm_open(tmp_name, O_CREAT | O_EXCL | O_RDWR, 0700);
- if (shmfd < 0) {
- PERROR("shm_open");
- goto error_shm_open;
- }
- ret = shm_unlink(tmp_name);
- if (ret < 0 && errno != ENOENT) {
- PERROR("shm_unlink");
- goto error_shm_release;
- }
- return shmfd;
-
-error_shm_release:
- ret = close(shmfd);
- if (ret) {
- PERROR("close");
- }
-error_shm_open:
- return -1;
-}
-
static int open_ust_stream_fd(struct lttng_consumer_channel *channel, int cpu,
const struct lttng_credentials *session_credentials)
{
int ret;
if (!channel->shm_path[0]) {
- return create_posix_shm();
+ return shm_create_anonymous("ust-consumer");
}
ret = get_stream_shm_path(shm_path, channel->shm_path, cpu);
if (ret) {
}
return run_as_open(shm_path,
O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR,
- session_credentials->uid, session_credentials->gid);
+ lttng_credentials_get_uid(session_credentials),
+ lttng_credentials_get_gid(session_credentials));
error_shm_path:
return -1;
ERR("Cannot get stream shm path");
}
closeret = run_as_unlink(shm_path,
- channel->buffer_credentials.value.uid,
- channel->buffer_credentials.value.gid);
+ lttng_credentials_get_uid(LTTNG_OPTIONAL_GET_PTR(
+ channel->buffer_credentials)),
+ lttng_credentials_get_gid(LTTNG_OPTIONAL_GET_PTR(
+ channel->buffer_credentials)));
if (closeret) {
PERROR("unlink %s", shm_path);
}
/* Try to rmdir all directories under shm_path root. */
if (channel->root_shm_path[0]) {
(void) run_as_rmdir_recursive(channel->root_shm_path,
- channel->buffer_credentials.value.uid,
- channel->buffer_credentials.value.gid,
+ lttng_credentials_get_uid(LTTNG_OPTIONAL_GET_PTR(
+ channel->buffer_credentials)),
+ lttng_credentials_get_gid(LTTNG_OPTIONAL_GET_PTR(
+ channel->buffer_credentials)),
LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG);
}
free(stream_fds);
subbuf_view = lttng_buffer_view_init(
subbuf_addr, 0, padded_len);
- read_len = lttng_consumer_on_read_subbuffer_mmap(ctx,
+ read_len = lttng_consumer_on_read_subbuffer_mmap(
stream, &subbuf_view, padded_len - len);
if (use_relayd) {
if (read_len != len) {
struct ustctl_consumer_channel_attr attr;
const uint64_t chunk_id = msg.u.ask_channel.chunk_id.value;
const struct lttng_credentials buffer_credentials = {
- .uid = msg.u.ask_channel.buffer_credentials.uid,
- .gid = msg.u.ask_channel.buffer_credentials.gid,
+ .uid = LTTNG_OPTIONAL_INIT_VALUE(msg.u.ask_channel.buffer_credentials.uid),
+ .gid = LTTNG_OPTIONAL_INIT_VALUE(msg.u.ask_channel.buffer_credentials.gid),
};
/* Create a plain object and reserve a channel key. */
case LTTNG_CONSUMER_CREATE_TRACE_CHUNK:
{
const struct lttng_credentials credentials = {
- .uid = msg.u.create_trace_chunk.credentials.value.uid,
- .gid = msg.u.create_trace_chunk.credentials.value.gid,
+ .uid = LTTNG_OPTIONAL_INIT_VALUE(msg.u.create_trace_chunk.credentials.value.uid),
+ .gid = LTTNG_OPTIONAL_INIT_VALUE(msg.u.create_trace_chunk.credentials.value.gid),
};
const bool is_local_trace =
!msg.u.create_trace_chunk.relayd_id.is_set;
msg.u.trace_chunk_exists.chunk_id);
goto end_msg_sessiond;
}
+ case LTTNG_CONSUMER_OPEN_CHANNEL_PACKETS:
+ {
+ const uint64_t key = msg.u.open_channel_packets.key;
+ struct lttng_consumer_channel *channel =
+ consumer_find_channel(key);
+
+ if (channel) {
+ pthread_mutex_lock(&channel->lock);
+ ret_code = lttng_consumer_open_channel_packets(channel);
+ pthread_mutex_unlock(&channel->lock);
+ } else {
+ /*
+ * The channel could have disappeared in per-pid
+ * buffering mode.
+ */
+ DBG("Channel %" PRIu64 " not found", key);
+ ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
+ }
+
+ health_code_update();
+ goto end_msg_sessiond;
+ }
default:
break;
}
ERR("Cannot get stream shm path");
}
ret = run_as_unlink(shm_path,
- chan->buffer_credentials.value.uid,
- chan->buffer_credentials.value.gid);
+ lttng_credentials_get_uid(LTTNG_OPTIONAL_GET_PTR(
+ chan->buffer_credentials)),
+ lttng_credentials_get_gid(LTTNG_OPTIONAL_GET_PTR(
+ chan->buffer_credentials)));
if (ret) {
PERROR("unlink %s", shm_path);
}
/* Try to rmdir all directories under shm_path root. */
if (chan->root_shm_path[0]) {
(void) run_as_rmdir_recursive(chan->root_shm_path,
- chan->buffer_credentials.value.uid,
- chan->buffer_credentials.value.gid,
+ lttng_credentials_get_uid(LTTNG_OPTIONAL_GET_PTR(
+ chan->buffer_credentials)),
+ lttng_credentials_get_gid(LTTNG_OPTIONAL_GET_PTR(
+ chan->buffer_credentials)),
LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG);
}
free(chan->stream_fds);
}
static
-void metadata_stream_reset_cache(struct lttng_consumer_stream *stream)
+void metadata_stream_reset_cache_consumed_position(
+ struct lttng_consumer_stream *stream)
{
DBG("Reset metadata cache of session %" PRIu64,
stream->chan->session_id);
stream->ust_metadata_pushed = 0;
- stream->metadata_version = stream->chan->metadata_cache->version;
- stream->reset_metadata_flag = 1;
}
/*
* Write up to one packet from the metadata cache to the channel.
*
- * Returns the number of bytes pushed in the cache, or a negative value
- * on error.
+ * Returns the number of bytes pushed from the cache into the ring buffer, or a
+ * negative value on error.
*/
static
int commit_one_metadata_packet(struct lttng_consumer_stream *stream)
int ret;
pthread_mutex_lock(&stream->chan->metadata_cache->lock);
- if (stream->chan->metadata_cache->max_offset
- == stream->ust_metadata_pushed) {
- ret = 0;
- goto end;
+ if (stream->chan->metadata_cache->max_offset ==
+ stream->ust_metadata_pushed) {
+ /*
+ * In the context of a user space metadata channel, a
+ * change in version can be detected in two ways:
+ * 1) During the pre-consume of the `read_subbuffer` loop,
+ * 2) When populating the metadata ring buffer (i.e. here).
+ *
+ * This function is invoked when there is no metadata
+ * available in the ring-buffer. If all data was consumed
+ * up to the size of the metadata cache, there is no metadata
+ * to insert in the ring-buffer.
+ *
+ * However, the metadata version could still have changed (a
+ * regeneration without any new data will yield the same cache
+ * size).
+ *
+ * The cache's version is checked for a version change and the
+ * consumed position is reset if one occurred.
+ *
+ * This check is only necessary for the user space domain as
+ * it has to manage the cache explicitly. If this reset was not
+ * performed, no metadata would be consumed (and no reset would
+ * occur as part of the pre-consume) until the metadata size
+ * exceeded the cache size.
+ */
+ if (stream->metadata_version !=
+ stream->chan->metadata_cache->version) {
+ metadata_stream_reset_cache_consumed_position(stream);
+ consumer_stream_metadata_set_version(stream,
+ stream->chan->metadata_cache->version);
+ } else {
+ ret = 0;
+ goto end;
+ }
}
write_len = ustctl_write_one_packet_to_channel(stream->chan->uchan,
assert(write_len != 0);
if (write_len < 0) {
ERR("Writing one metadata packet");
- ret = -1;
+ ret = write_len;
goto end;
}
stream->ust_metadata_pushed += write_len;
* awaiting on metadata to be pushed out.
*
* The RCU read side lock must be held by the caller.
- *
- * Return 0 if new metadatda is available, EAGAIN if the metadata stream
- * is empty or a negative value on error.
*/
-int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data *ctx,
+enum sync_metadata_status lttng_ustconsumer_sync_metadata(
+ struct lttng_consumer_local_data *ctx,
struct lttng_consumer_stream *metadata_stream)
{
int ret;
- int retry = 0;
+ enum sync_metadata_status status;
struct lttng_consumer_channel *metadata_channel;
assert(ctx);
ret = lttng_ustconsumer_request_metadata(ctx, metadata_channel, 0, 0);
pthread_mutex_lock(&metadata_stream->lock);
if (ret < 0) {
+ status = SYNC_METADATA_STATUS_ERROR;
goto end;
}
if (consumer_stream_is_deleted(metadata_stream)) {
DBG("Metadata stream %" PRIu64 " was deleted during the metadata synchronization",
metadata_stream->key);
- ret = 0;
+ status = SYNC_METADATA_STATUS_NO_DATA;
goto end;
}
ret = commit_one_metadata_packet(metadata_stream);
- if (ret <= 0) {
+ if (ret < 0) {
+ status = SYNC_METADATA_STATUS_ERROR;
goto end;
} else if (ret > 0) {
- retry = 1;
+ status = SYNC_METADATA_STATUS_NEW_DATA;
+ } else /* ret == 0 */ {
+ status = SYNC_METADATA_STATUS_NO_DATA;
+ goto end;
}
ret = ustctl_snapshot(metadata_stream->ustream);
if (ret < 0) {
- if (errno != EAGAIN) {
- ERR("Sync metadata, taking UST snapshot");
- goto end;
- }
- DBG("No new metadata when syncing them.");
- /* No new metadata, exit. */
- ret = ENODATA;
+ ERR("Failed to take a snapshot of the metadata ring-buffer positions, ret = %d", ret);
+ status = SYNC_METADATA_STATUS_ERROR;
goto end;
}
- /*
- * After this flush, we still need to extract metadata.
- */
- if (retry) {
- ret = EAGAIN;
- }
-
end:
- return ret;
+ return status;
}
/*
goto end;
}
- subbuf->info.metadata.version = stream->chan->metadata_cache->version;
+ subbuf->info.metadata.version = stream->metadata_version;
end:
return ret;
struct stream_subbuffer *subbuffer)
{
int ret;
+ bool cache_empty;
+ bool got_subbuffer;
+ bool coherent;
+ bool buffer_empty;
+ unsigned long consumed_pos, produced_pos;
- ret = ustctl_get_next_subbuf(stream->ustream);
- if (ret) {
- ret = commit_one_metadata_packet(stream);
- if (ret < 0) {
- goto end;
- } else if (ret == 0) {
- /* Not an error, the cache is empty. */
- ret = -ENODATA;
- goto end;
+ do {
+ ret = ustctl_get_next_subbuf(stream->ustream);
+ if (ret == 0) {
+ got_subbuffer = true;
+ } else {
+ got_subbuffer = false;
+ if (ret != -EAGAIN) {
+ /* Fatal error. */
+ goto end;
+ }
}
- ret = ustctl_get_next_subbuf(stream->ustream);
- if (ret) {
- goto end;
+ /*
+ * Determine if the cache is empty and ensure that a sub-buffer
+ * is made available if the cache is not empty.
+ */
+ if (!got_subbuffer) {
+ ret = commit_one_metadata_packet(stream);
+ if (ret < 0 && ret != -ENOBUFS) {
+ goto end;
+ } else if (ret == 0) {
+ /* Not an error, the cache is empty. */
+ cache_empty = true;
+ ret = -ENODATA;
+ goto end;
+ } else {
+ cache_empty = false;
+ }
+ } else {
+ pthread_mutex_lock(&stream->chan->metadata_cache->lock);
+ cache_empty = stream->chan->metadata_cache->max_offset ==
+ stream->ust_metadata_pushed;
+ pthread_mutex_unlock(&stream->chan->metadata_cache->lock);
}
- }
+ } while (!got_subbuffer);
+ /* Populate sub-buffer infos and view. */
ret = get_next_subbuffer_common(stream, subbuffer);
if (ret) {
goto end;
}
+
+ ret = lttng_ustconsumer_sample_snapshot_positions(stream);
+ if (ret < 0) {
+ /*
+ * -EAGAIN is not expected since we got a sub-buffer and haven't
+ * pushed the consumption position yet (on put_next).
+ */
+ PERROR("Failed to take a snapshot of metadata buffer positions");
+ goto end;
+ }
+
+ ret = lttng_ustconsumer_get_consumed_snapshot(stream, &consumed_pos);
+ if (ret) {
+ PERROR("Failed to get metadata consumed position");
+ goto end;
+ }
+
+ ret = lttng_ustconsumer_get_produced_snapshot(stream, &produced_pos);
+ if (ret) {
+ PERROR("Failed to get metadata produced position");
+ goto end;
+ }
+
+ /* Last sub-buffer of the ring buffer ? */
+ buffer_empty = (consumed_pos + stream->max_sb_size) == produced_pos;
+
+ /*
+ * The sessiond registry lock ensures that coherent units of metadata
+ * are pushed to the consumer daemon at once. Hence, if a sub-buffer is
+ * acquired, the cache is empty, and it is the only available sub-buffer
+ * available, it is safe to assume that it is "coherent".
+ */
+ coherent = got_subbuffer && cache_empty && buffer_empty;
+
+ LTTNG_OPTIONAL_SET(&subbuffer->info.metadata.coherent, coherent);
end:
return ret;
}
return pthread_cond_broadcast(&stream->metadata_rdv) ? -errno : 0;
}
-static void lttng_ustconsumer_set_stream_ops(
+static int lttng_ustconsumer_set_stream_ops(
struct lttng_consumer_stream *stream)
{
+ int ret = 0;
+
stream->read_subbuffer_ops.on_wake_up = consumer_stream_ust_on_wake_up;
if (stream->metadata_flag) {
stream->read_subbuffer_ops.get_next_subbuffer =
stream->read_subbuffer_ops.extract_subbuffer_info =
extract_metadata_subbuffer_info;
stream->read_subbuffer_ops.reset_metadata =
- metadata_stream_reset_cache;
- stream->read_subbuffer_ops.on_sleep = signal_metadata;
+ metadata_stream_reset_cache_consumed_position;
+ if (stream->chan->is_live) {
+ stream->read_subbuffer_ops.on_sleep = signal_metadata;
+ ret = consumer_stream_enable_metadata_bucketization(
+ stream);
+ if (ret) {
+ goto end;
+ }
+ }
} else {
stream->read_subbuffer_ops.get_next_subbuffer =
get_next_subbuffer;
}
stream->read_subbuffer_ops.put_next_subbuffer = put_next_subbuffer;
+end:
+ return ret;
}
/*
projects / lttng-tools.git / blobdiff