summary |
shortlog |
log |
commit | commitdiff |
tree
raw |
patch |
inline | side by side (from parent 1:
b773bad)
Accessing the lttng channel and lttng session from the metadata ring
buffer client is a bad idea, because we don't have any reference
ensuring those are valid for the lifetime of the metadata cache.
Therefore, rather than keeping a lttng channel as private data pointer
for the metadata ring buffer channel, keep a pointer to the metadata
cache instead: this will ensure we don't shoot ourself in the foot and
access data we for which coherency is not guaranteed (we don't hold any
reference to it).
Anyway, the only reason why we needed to access the lttng session from
the metadata client in the first place was the UUID of the session. Copy
it into the metadata cache instead.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
kref_init(&metadata_cache->refcount);
session->metadata_cache = metadata_cache;
INIT_LIST_HEAD(&metadata_cache->metadata_stream);
kref_init(&metadata_cache->refcount);
session->metadata_cache = metadata_cache;
INIT_LIST_HEAD(&metadata_cache->metadata_stream);
+ memcpy(&metadata_cache->uuid, &session->uuid,
+ sizeof(metadata_cache->uuid));
list_add(&session->list, &sessions);
mutex_unlock(&sessions_mutex);
return session;
list_add(&session->list, &sessions);
mutex_unlock(&sessions_mutex);
return session;
unsigned int metadata_written; /* Number of bytes written in metadata cache */
struct kref refcount; /* Metadata cache usage */
struct list_head metadata_stream; /* Metadata stream list */
unsigned int metadata_written; /* Number of bytes written in metadata cache */
struct kref refcount; /* Metadata cache usage */
struct list_head metadata_stream; /* Metadata stream list */
+ uuid_le uuid; /* Trace session unique ID (copy) */
};
struct lttng_session *lttng_session_create(void);
};
struct lttng_session *lttng_session_create(void);
(struct metadata_packet_header *)
lib_ring_buffer_offset_address(&buf->backend,
subbuf_idx * chan->backend.subbuf_size);
(struct metadata_packet_header *)
lib_ring_buffer_offset_address(&buf->backend,
subbuf_idx * chan->backend.subbuf_size);
- struct lttng_channel *lttng_chan = channel_get_private(chan);
- struct lttng_session *session = lttng_chan->session;
+ struct lttng_metadata_cache *metadata_cache =
+ channel_get_private(chan);
header->magic = TSDL_MAGIC_NUMBER;
header->magic = TSDL_MAGIC_NUMBER;
- memcpy(header->uuid, session->uuid.b, sizeof(session->uuid));
+ memcpy(header->uuid, metadata_cache->uuid.b,
+ sizeof(metadata_cache->uuid));
header->checksum = 0; /* 0 if unused */
header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
header->checksum = 0; /* 0 if unused */
header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
- chan = channel_create(&client_config, name, lttng_chan, buf_addr,
+ chan = channel_create(&client_config, name,
+ lttng_chan->session->metadata_cache, buf_addr,
subbuf_size, num_subbuf, switch_timer_interval,
read_timer_interval);
if (chan) {
subbuf_size, num_subbuf, switch_timer_interval,
read_timer_interval);
if (chan) {