#include "ust-consumer.h"
#include "ust-ctl.h"
+/* Next available channel key. */
+static unsigned long next_channel_key;
+
+/*
+ * Return the atomically incremented value of next_channel_key.
+ */
+static inline unsigned long get_next_channel_key(void)
+{
+ return uatomic_add_return(&next_channel_key, 1);
+}
+
+/*
+ * Return the consumer socket from the given consumer output with the right
+ * bitness. On error, returns NULL.
+ *
+ * The caller MUST acquire a rcu read side lock and keep it until the socket
+ * object reference is not needed anymore.
+ */
+static struct consumer_socket *find_consumer_socket_by_bitness(int bits,
+ struct consumer_output *consumer)
+{
+ int consumer_fd;
+ struct consumer_socket *socket = NULL;
+
+ switch (bits) {
+ case 64:
+ consumer_fd = uatomic_read(&ust_consumerd64_fd);
+ break;
+ case 32:
+ consumer_fd = uatomic_read(&ust_consumerd32_fd);
+ break;
+ default:
+ assert(0);
+ goto end;
+ }
+
+ socket = consumer_find_socket(consumer_fd, consumer);
+ if (!socket) {
+ ERR("Consumer socket fd %d not found in consumer obj %p",
+ consumer_fd, consumer);
+ }
+
+end:
+ return socket;
+}
+
/*
* Match function for the hash table lookup.
*
* Unique add of an ust app event in the given ht. This uses the custom
* ht_match_ust_app_event match function and the event name as hash.
*/
-static void add_unique_ust_app_event(struct lttng_ht *ht,
+static void add_unique_ust_app_event(struct ust_app_channel *ua_chan,
struct ust_app_event *event)
{
struct cds_lfht_node *node_ptr;
struct ust_app_ht_key key;
+ struct lttng_ht *ht;
- assert(ht);
- assert(ht->ht);
+ assert(ua_chan);
+ assert(ua_chan->events);
assert(event);
+ ht = ua_chan->events;
key.name = event->attr.name;
key.filter = event->filter;
key.loglevel = event->attr.loglevel;
assert(node_ptr == &event->node.node);
}
+/*
+ * Close the notify socket from the given RCU head object. This MUST be called
+ * through a call_rcu().
+ */
+static void close_notify_sock_rcu(struct rcu_head *head)
+{
+ int ret;
+ struct ust_app_notify_sock_obj *obj =
+ caa_container_of(head, struct ust_app_notify_sock_obj, head);
+
+ /* Must have a valid fd here. */
+ assert(obj->fd >= 0);
+
+ ret = close(obj->fd);
+ if (ret) {
+ ERR("close notify sock %d RCU", obj->fd);
+ }
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+
+ free(obj);
+}
+
/*
* Delete ust context safely. RCU read lock must be held before calling
* this function.
static
void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx)
{
+ int ret;
+
+ assert(ua_ctx);
+
if (ua_ctx->obj) {
- ustctl_release_object(sock, ua_ctx->obj);
+ ret = ustctl_release_object(sock, ua_ctx->obj);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app sock %d release ctx obj handle %d failed with ret %d",
+ sock, ua_ctx->obj->handle, ret);
+ }
free(ua_ctx->obj);
}
free(ua_ctx);
static
void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
{
+ int ret;
+
+ assert(ua_event);
+
free(ua_event->filter);
if (ua_event->obj != NULL) {
- ustctl_release_object(sock, ua_event->obj);
+ ret = ustctl_release_object(sock, ua_event->obj);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app sock %d release event obj failed with ret %d",
+ sock, ret);
+ }
free(ua_event->obj);
}
free(ua_event);
static
void delete_ust_app_stream(int sock, struct ust_app_stream *stream)
{
+ int ret;
+
+ assert(stream);
+
if (stream->obj) {
- ustctl_release_object(sock, stream->obj);
+ ret = ustctl_release_object(sock, stream->obj);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app sock %d release stream obj failed with ret %d",
+ sock, ret);
+ }
lttng_fd_put(LTTNG_FD_APPS, 2);
free(stream->obj);
}
* this function.
*/
static
-void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan)
+void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan,
+ struct ust_app *app)
{
int ret;
struct lttng_ht_iter iter;
struct ust_app_ctx *ua_ctx;
struct ust_app_stream *stream, *stmp;
+ assert(ua_chan);
+
+ DBG3("UST app deleting channel %s", ua_chan->name);
+
/* Wipe stream */
cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
cds_list_del(&stream->list);
}
lttng_ht_destroy(ua_chan->events);
+ /* Wipe and free registry. */
+ ust_registry_channel_destroy(&ua_chan->session->registry, &ua_chan->registry);
+
if (ua_chan->obj != NULL) {
- ustctl_release_object(sock, ua_chan->obj);
+ /* Remove channel from application UST object descriptor. */
+ iter.iter.node = &ua_chan->ust_objd_node.node;
+ lttng_ht_del(app->ust_objd, &iter);
+ ret = ustctl_release_object(sock, ua_chan->obj);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app sock %d release channel obj failed with ret %d",
+ sock, ret);
+ }
lttng_fd_put(LTTNG_FD_APPS, 2);
free(ua_chan->obj);
}
free(ua_chan);
}
+/*
+ * For a given application and session, push metadata to consumer. The session
+ * lock MUST be acquired here before calling this.
+ *
+ * Return 0 on success else a negative error.
+ */
+static int push_metadata(struct ust_app *app, struct ust_app_session *ua_sess)
+{
+ int ret;
+ char *metadata_str = NULL;
+ size_t len, offset;
+ struct consumer_socket *socket;
+
+ assert(app);
+ assert(ua_sess);
+
+ if (!ua_sess->consumer || !ua_sess->metadata) {
+ /* No consumer means no stream associated so just return gracefully. */
+ ret = 0;
+ goto end;
+ }
+
+ rcu_read_lock();
+
+ /* Get consumer socket to use to push the metadata.*/
+ socket = find_consumer_socket_by_bitness(app->bits_per_long,
+ ua_sess->consumer);
+ if (!socket) {
+ ret = -1;
+ goto error_rcu_unlock;
+ }
+
+ /*
+ * TODO: Currently, we hold the socket lock around sampling of the next
+ * metadata segment to ensure we send metadata over the consumer socket in
+ * the correct order. This makes the registry lock nest inside the socket
+ * lock.
+ *
+ * Please note that this is a temporary measure: we should move this lock
+ * back into ust_consumer_push_metadata() when the consumer gets the
+ * ability to reorder the metadata it receives.
+ */
+ pthread_mutex_lock(socket->lock);
+ pthread_mutex_lock(&ua_sess->registry.lock);
+
+ offset = ua_sess->registry.metadata_len_sent;
+ len = ua_sess->registry.metadata_len - ua_sess->registry.metadata_len_sent;
+ if (len == 0) {
+ DBG3("No metadata to push for session id %d", ua_sess->id);
+ ret = 0;
+ goto error_reg_unlock;
+ }
+ assert(len > 0);
+
+ /* Allocate only what we have to send. */
+ metadata_str = zmalloc(len);
+ if (!metadata_str) {
+ PERROR("zmalloc ust app metadata string");
+ ret = -ENOMEM;
+ goto error_reg_unlock;
+ }
+ /* Copy what we haven't send out. */
+ memcpy(metadata_str, ua_sess->registry.metadata + offset, len);
+
+ pthread_mutex_unlock(&ua_sess->registry.lock);
+
+ ret = ust_consumer_push_metadata(socket, ua_sess, metadata_str, len,
+ offset);
+ if (ret < 0) {
+ pthread_mutex_unlock(socket->lock);
+ goto error_rcu_unlock;
+ }
+
+ /* Update len sent of the registry. */
+ pthread_mutex_lock(&ua_sess->registry.lock);
+ ua_sess->registry.metadata_len_sent += len;
+ pthread_mutex_unlock(&ua_sess->registry.lock);
+ pthread_mutex_unlock(socket->lock);
+
+ rcu_read_unlock();
+ free(metadata_str);
+ return 0;
+
+error_reg_unlock:
+ pthread_mutex_unlock(&ua_sess->registry.lock);
+ pthread_mutex_unlock(socket->lock);
+error_rcu_unlock:
+ rcu_read_unlock();
+ free(metadata_str);
+end:
+ return ret;
+}
+
+/*
+ * Send to the consumer a close metadata command for the given session. Once
+ * done, the metadata channel is deleted and the session metadata pointer is
+ * nullified. The session lock MUST be acquired here unless the application is
+ * in the destroy path.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int close_metadata(struct ust_app *app, struct ust_app_session *ua_sess)
+{
+ int ret;
+ struct consumer_socket *socket;
+
+ assert(app);
+ assert(ua_sess);
+
+ /* Ignore if no metadata. Valid since it can be called on unregister. */
+ if (!ua_sess->metadata) {
+ ret = 0;
+ goto error;
+ }
+
+ rcu_read_lock();
+
+ /* Get consumer socket to use to push the metadata.*/
+ socket = find_consumer_socket_by_bitness(app->bits_per_long,
+ ua_sess->consumer);
+ if (!socket) {
+ ret = -1;
+ goto error_rcu_unlock;
+ }
+
+ ret = ust_consumer_close_metadata(socket, ua_sess->metadata);
+ if (ret < 0) {
+ goto error_rcu_unlock;
+ }
+
+error_rcu_unlock:
+ /* Destroy metadata on our side since we must not use it anymore. */
+ delete_ust_app_channel(-1, ua_sess->metadata, app);
+ ua_sess->metadata = NULL;
+
+ rcu_read_unlock();
+error:
+ return ret;
+}
+
/*
* Delete ust app session safely. RCU read lock must be held before calling
* this function.
*/
static
-void delete_ust_app_session(int sock, struct ust_app_session *ua_sess)
+void delete_ust_app_session(int sock, struct ust_app_session *ua_sess,
+ struct ust_app *app)
{
int ret;
struct lttng_ht_iter iter;
struct ust_app_channel *ua_chan;
+ assert(ua_sess);
+
if (ua_sess->metadata) {
- if (ua_sess->metadata->stream_obj) {
- ustctl_release_object(sock, ua_sess->metadata->stream_obj);
- lttng_fd_put(LTTNG_FD_APPS, 2);
- free(ua_sess->metadata->stream_obj);
- }
- if (ua_sess->metadata->obj) {
- ustctl_release_object(sock, ua_sess->metadata->obj);
- lttng_fd_put(LTTNG_FD_APPS, 2);
- free(ua_sess->metadata->obj);
- }
- trace_ust_destroy_metadata(ua_sess->metadata);
+ /* Push metadata for application before freeing the application. */
+ (void) push_metadata(app, ua_sess);
+
+ /* And ask to close it for this session. */
+ (void) close_metadata(app, ua_sess);
}
cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
node.node) {
ret = lttng_ht_del(ua_sess->channels, &iter);
assert(!ret);
- delete_ust_app_channel(sock, ua_chan);
+ delete_ust_app_channel(sock, ua_chan, app);
}
lttng_ht_destroy(ua_sess->channels);
+ ust_registry_session_destroy(&ua_sess->registry);
+
if (ua_sess->handle != -1) {
- ustctl_release_handle(sock, ua_sess->handle);
+ ret = ustctl_release_handle(sock, ua_sess->handle);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app sock %d release session handle failed with ret %d",
+ sock, ret);
+ }
}
free(ua_sess);
}
cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head,
teardown_node) {
/* Free every object in the session and the session. */
- delete_ust_app_session(sock, ua_sess);
+ delete_ust_app_session(sock, ua_sess, app);
}
/*
delete_ust_app(app);
}
+/*
+ * Delete the session from the application ht and delete the data structure by
+ * freeing every object inside and releasing them.
+ */
+static void destroy_app_session(struct ust_app *app,
+ struct ust_app_session *ua_sess)
+{
+ int ret;
+ struct lttng_ht_iter iter;
+
+ assert(app);
+ assert(ua_sess);
+
+ iter.iter.node = &ua_sess->node.node;
+ ret = lttng_ht_del(app->sessions, &iter);
+ if (ret) {
+ /* Already scheduled for teardown. */
+ goto end;
+ }
+
+ /* Once deleted, free the data structure. */
+ delete_ust_app_session(app->sock, ua_sess, app);
+
+end:
+ return;
+}
+
/*
* Alloc new UST app session.
*/
static
-struct ust_app_session *alloc_ust_app_session(void)
+struct ust_app_session *alloc_ust_app_session(struct ust_app *app)
{
struct ust_app_session *ua_sess;
ua_sess = zmalloc(sizeof(struct ust_app_session));
if (ua_sess == NULL) {
PERROR("malloc");
- goto error;
+ goto error_free;
}
ua_sess->handle = -1;
ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
+ pthread_mutex_init(&ua_sess->lock, NULL);
+ if (ust_registry_session_init(&ua_sess->registry, app,
+ app->bits_per_long,
+ app->uint8_t_alignment,
+ app->uint16_t_alignment,
+ app->uint32_t_alignment,
+ app->uint64_t_alignment,
+ app->long_alignment,
+ app->byte_order)) {
+ goto error;
+ }
return ua_sess;
error:
+ free(ua_sess);
+error_free:
return NULL;
}
*/
static
struct ust_app_channel *alloc_ust_app_channel(char *name,
- struct lttng_ust_channel *attr)
+ struct ust_app_session *ua_sess,
+ struct lttng_ust_channel_attr *attr)
{
struct ust_app_channel *ua_chan;
ua_chan->enabled = 1;
ua_chan->handle = -1;
+ ua_chan->key = get_next_channel_key();
ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
lttng_ht_node_init_str(&ua_chan->node, ua_chan->name);
CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
+ /* Initialize UST registry. */
+ ust_registry_channel_init(&ua_sess->registry, &ua_chan->registry);
+
/* Copy attributes */
if (attr) {
- memcpy(&ua_chan->attr, attr, sizeof(ua_chan->attr));
+ /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
+ ua_chan->attr.subbuf_size = attr->subbuf_size;
+ ua_chan->attr.num_subbuf = attr->num_subbuf;
+ ua_chan->attr.overwrite = attr->overwrite;
+ ua_chan->attr.switch_timer_interval = attr->switch_timer_interval;
+ ua_chan->attr.read_timer_interval = attr->read_timer_interval;
+ ua_chan->attr.output = attr->output;
}
+ /* By default, the channel is a per cpu channel. */
+ ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
DBG3("UST app channel %s allocated", ua_chan->name);
*
* Return newly allocated stream pointer or NULL on error.
*/
-static struct ust_app_stream *alloc_ust_app_stream(void)
+struct ust_app_stream *ust_app_alloc_stream(void)
{
struct ust_app_stream *stream = NULL;
return NULL;
}
+/*
+ * Find an ust_app using the notify sock and return it. RCU read side lock must
+ * be held before calling this helper function.
+ */
+static struct ust_app *find_app_by_notify_sock(int sock)
+{
+ struct lttng_ht_node_ulong *node;
+ struct lttng_ht_iter iter;
+
+ lttng_ht_lookup(ust_app_ht_by_notify_sock, (void *)((unsigned long) sock),
+ &iter);
+ node = lttng_ht_iter_get_node_ulong(&iter);
+ if (node == NULL) {
+ DBG2("UST app find by notify sock %d not found", sock);
+ goto error;
+ }
+
+ return caa_container_of(node, struct ust_app, notify_sock_n);
+
+error:
+ return NULL;
+}
+
/*
* Lookup for an ust app event based on event name, filter bytecode and the
* event loglevel.
/*
* Create the channel context on the tracer.
+ *
+ * Called with UST app session lock held.
*/
static
int create_ust_channel_context(struct ust_app_channel *ua_chan,
{
int ret;
- health_code_update(&health_thread_cmd);
+ health_code_update();
ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
ua_chan->obj, &ua_ctx->obj);
if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app create channel context failed for app (pid: %d) "
+ "with ret %d", app->pid, ret);
+ } else {
+ DBG3("UST app disable event failed. Application is dead.");
+ }
goto error;
}
ua_ctx->handle = ua_ctx->obj->handle;
- DBG2("UST app context created successfully for channel %s", ua_chan->name);
+ DBG2("UST app context handle %d created successfully for channel %s",
+ ua_ctx->handle, ua_chan->name);
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
{
int ret;
- health_code_update(&health_thread_cmd);
+ health_code_update();
if (!ua_event->filter) {
ret = 0;
ret = ustctl_set_filter(app->sock, ua_event->filter,
ua_event->obj);
if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app event %s filter failed for app (pid: %d) "
+ "with ret %d", ua_event->attr.name, app->pid, ret);
+ } else {
+ DBG3("UST app filter event failed. Application is dead.");
+ }
goto error;
}
DBG2("UST filter set successfully for event %s", ua_event->name);
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
{
int ret;
- health_code_update(&health_thread_cmd);
+ health_code_update();
ret = ustctl_disable(app->sock, ua_event->obj);
if (ret < 0) {
- ERR("UST app event %s disable failed for app (pid: %d) "
- "and session handle %d with ret %d",
- ua_event->attr.name, app->pid, ua_sess->handle, ret);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app event %s disable failed for app (pid: %d) "
+ "and session handle %d with ret %d",
+ ua_event->attr.name, app->pid, ua_sess->handle, ret);
+ } else {
+ DBG3("UST app disable event failed. Application is dead.");
+ }
goto error;
}
ua_event->attr.name, app->pid);
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
{
int ret;
- health_code_update(&health_thread_cmd);
+ health_code_update();
ret = ustctl_disable(app->sock, ua_chan->obj);
if (ret < 0) {
- ERR("UST app channel %s disable failed for app (pid: %d) "
- "and session handle %d with ret %d",
- ua_chan->name, app->pid, ua_sess->handle, ret);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app channel %s disable failed for app (pid: %d) "
+ "and session handle %d with ret %d",
+ ua_chan->name, app->pid, ua_sess->handle, ret);
+ } else {
+ DBG3("UST app disable channel failed. Application is dead.");
+ }
goto error;
}
ua_chan->name, app->pid);
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
{
int ret;
- health_code_update(&health_thread_cmd);
+ health_code_update();
ret = ustctl_enable(app->sock, ua_chan->obj);
if (ret < 0) {
- ERR("UST app channel %s enable failed for app (pid: %d) "
- "and session handle %d with ret %d",
- ua_chan->name, app->pid, ua_sess->handle, ret);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app channel %s enable failed for app (pid: %d) "
+ "and session handle %d with ret %d",
+ ua_chan->name, app->pid, ua_sess->handle, ret);
+ } else {
+ DBG3("UST app enable channel failed. Application is dead.");
+ }
goto error;
}
ua_chan->name, app->pid);
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
{
int ret;
- health_code_update(&health_thread_cmd);
+ health_code_update();
ret = ustctl_enable(app->sock, ua_event->obj);
if (ret < 0) {
- ERR("UST app event %s enable failed for app (pid: %d) "
- "and session handle %d with ret %d",
- ua_event->attr.name, app->pid, ua_sess->handle, ret);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app event %s enable failed for app (pid: %d) "
+ "and session handle %d with ret %d",
+ ua_event->attr.name, app->pid, ua_sess->handle, ret);
+ } else {
+ DBG3("UST app enable event failed. Application is dead.");
+ }
goto error;
}
ua_event->attr.name, app->pid);
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
/*
- * Open metadata onto the UST tracer for a UST session.
+ * Create the specified channel onto the UST tracer for a UST session. This
+ * MUST be called with UST app session lock held.
+ *
+ * Return 0 on success. On error, a negative value is returned.
*/
-static int open_ust_metadata(struct ust_app *app,
- struct ust_app_session *ua_sess)
+static int create_ust_channel(struct ust_app *app,
+ struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
+ struct consumer_output *consumer)
{
int ret;
- struct lttng_ust_channel_attr uattr;
+ unsigned int nb_fd = 0;
+ struct consumer_socket *socket;
+ struct ust_app_stream *stream, *stmp;
- health_code_update(&health_thread_cmd);
+ assert(app);
+ assert(ua_sess);
+ assert(ua_chan);
+ assert(consumer);
- uattr.overwrite = ua_sess->metadata->attr.overwrite;
- uattr.subbuf_size = ua_sess->metadata->attr.subbuf_size;
- uattr.num_subbuf = ua_sess->metadata->attr.num_subbuf;
- uattr.switch_timer_interval =
- ua_sess->metadata->attr.switch_timer_interval;
- uattr.read_timer_interval =
- ua_sess->metadata->attr.read_timer_interval;
- uattr.output = ua_sess->metadata->attr.output;
+ rcu_read_lock();
+ health_code_update();
- /* We are going to receive 2 fds, we need to reserve them. */
- ret = lttng_fd_get(LTTNG_FD_APPS, 2);
- if (ret < 0) {
- ERR("Exhausted number of available FD upon metadata open");
- goto error;
- }
- /* UST tracer metadata creation */
- ret = ustctl_open_metadata(app->sock, ua_sess->handle, &uattr,
- &ua_sess->metadata->obj);
- if (ret < 0) {
- ERR("UST app open metadata failed for app pid:%d with ret %d",
- app->pid, ret);
+ /* Get the right consumer socket for the application. */
+ socket = find_consumer_socket_by_bitness(app->bits_per_long, consumer);
+ if (!socket) {
+ ret = -1;
goto error;
}
- ua_sess->metadata->handle = ua_sess->metadata->obj->handle;
-
-error:
- health_code_update(&health_thread_cmd);
- return ret;
-}
-
-/*
- * Create metadata stream onto the UST tracer for a given session.
- */
-static int create_ust_metadata_stream(struct ust_app *app,
- struct ust_app_session *ua_sess)
-{
- int ret;
-
- health_code_update(&health_thread_cmd);
+ health_code_update();
- /* We are going to receive 2 fds, we need to reserve them. */
- ret = lttng_fd_get(LTTNG_FD_APPS, 2);
- if (ret < 0) {
- ERR("Exhausted number of available FD upon metadata stream create");
- goto error;
- }
- ret = ustctl_create_stream(app->sock, ua_sess->metadata->obj,
- &ua_sess->metadata->stream_obj);
+ /*
+ * Ask consumer to create channel. The consumer will return the number of
+ * stream we have to expect.
+ */
+ ret = ust_consumer_ask_channel(ua_sess, ua_chan, consumer, socket);
if (ret < 0) {
- lttng_fd_put(LTTNG_FD_APPS, 2);
- ERR("UST create metadata stream failed");
goto error;
}
-error:
- health_code_update(&health_thread_cmd);
- return ret;
-}
-
-/*
- * Create stream onto the UST tracer for a given channel.
- *
- * Return -ENOENT if no more stream is available for this channel.
- * On success, return 0.
- * On error, return a negative value.
- */
-static int create_ust_stream(struct ust_app *app,
- struct ust_app_channel *ua_chan, struct ust_app_stream *stream)
-{
- int ret;
-
- assert(app);
- assert(ua_chan);
- assert(ua_chan->obj);
- assert(stream);
-
- health_code_update(&health_thread_cmd);
+ /*
+ * Compute the number of fd needed before receiving them. It must be 2 per
+ * stream (2 being the default value here).
+ */
+ nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
- /* We are going to receive 2 fds, we need to reserve them. */
- ret = lttng_fd_get(LTTNG_FD_APPS, 2);
+ /* Reserve the amount of file descriptor we need. */
+ ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
if (ret < 0) {
- ERR("Exhausted number of available FD on stream creation");
- /* Just to make sure we never return -ENOENT. */
- ret = -1;
- goto error;
+ ERR("Exhausted number of available FD upon create channel");
+ goto error_fd_get;
}
+ health_code_update();
+
/*
- * Set the stream name before creating it. On error, we don't have to
- * delete it on the tracer side.
+ * Now get the channel from the consumer. This call wil populate the stream
+ * list of that channel and set the ust object.
*/
- ret = snprintf(stream->name, sizeof(stream->name), "%s_%u",
- ua_chan->name, ua_chan->streams.count);
+ ret = ust_consumer_get_channel(socket, ua_chan);
if (ret < 0) {
- /* Without the stream name we can't continue using it. */
- PERROR("snprintf UST create stream");
- /* Just to make sure we never return -ENOENT. */
- ret = -1;
- goto error;
+ goto error_destroy;
}
- ret = ustctl_create_stream(app->sock, ua_chan->obj, &stream->obj);
+ /* Send channel to the application. */
+ ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
if (ret < 0) {
- lttng_fd_put(LTTNG_FD_APPS, 2);
- /* Indicates that there is no more stream for that channel. */
- if (ret != -LTTNG_UST_ERR_NOENT) {
- ERR("UST create metadata stream failed (ret: %d)", ret);
- }
goto error;
}
- /* Set stream handle with the returned value. */
- stream->handle = stream->obj->handle;
+ health_code_update();
-error:
- health_code_update(&health_thread_cmd);
- return ret;
-}
-
-/*
- * Create the specified channel onto the UST tracer for a UST session.
- */
-static int create_ust_channel(struct ust_app *app,
- struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
-{
- int ret;
-
- health_code_update(&health_thread_cmd);
-
- /* TODO: remove cast and use lttng-ust-abi.h */
-
- /* We are going to receive 2 fds, we need to reserve them. */
- ret = lttng_fd_get(LTTNG_FD_APPS, 2);
- if (ret < 0) {
- ERR("Exhausted number of available FD upon create channel");
- goto error;
- }
-
- health_code_update(&health_thread_cmd);
-
- ret = ustctl_create_channel(app->sock, ua_sess->handle,
- (struct lttng_ust_channel_attr *)&ua_chan->attr, &ua_chan->obj);
- if (ret < 0) {
- ERR("Creating channel %s for app (pid: %d, sock: %d) "
- "and session handle %d with ret %d",
- ua_chan->name, app->pid, app->sock,
- ua_sess->handle, ret);
- lttng_fd_put(LTTNG_FD_APPS, 2);
- goto error;
+ /* Send all streams to application. */
+ cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
+ ret = ust_consumer_send_stream_to_ust(app, ua_chan, stream);
+ if (ret < 0) {
+ goto error;
+ }
+ /* We don't need the stream anymore once sent to the tracer. */
+ cds_list_del(&stream->list);
+ delete_ust_app_stream(-1, stream);
}
- ua_chan->handle = ua_chan->obj->handle;
+ /* Flag the channel that it is sent to the application. */
+ ua_chan->is_sent = 1;
+ /* Assign session to channel. */
+ ua_chan->session = ua_sess;
+ /* Initialize ust objd object using the received handle and add it. */
+ lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
+ lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
- DBG2("UST app channel %s created successfully for pid:%d and sock:%d",
- ua_chan->name, app->pid, app->sock);
-
- health_code_update(&health_thread_cmd);
+ health_code_update();
/* If channel is not enabled, disable it on the tracer */
if (!ua_chan->enabled) {
}
}
+ rcu_read_unlock();
+ return 0;
+
+error_destroy:
+ lttng_fd_put(LTTNG_FD_APPS, nb_fd);
+error_fd_get:
+ /*
+ * Initiate a destroy channel on the consumer since we had an error
+ * handling it on our side. The return value is of no importance since we
+ * already have a ret value set by the previous error that we need to
+ * return.
+ */
+ (void) ust_consumer_destroy_channel(socket, ua_chan);
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
+ rcu_read_unlock();
return ret;
}
/*
* Create the specified event onto the UST tracer for a UST session.
+ *
+ * Should be called with session mutex held.
*/
static
int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
{
int ret = 0;
- health_code_update(&health_thread_cmd);
+ health_code_update();
/* Create UST event on tracer */
ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
&ua_event->obj);
if (ret < 0) {
- ERR("Error ustctl create event %s for app pid: %d with ret %d",
- ua_event->attr.name, app->pid, ret);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("Error ustctl create event %s for app pid: %d with ret %d",
+ ua_event->attr.name, app->pid, ret);
+ } else {
+ DBG3("UST app create event failed. Application is dead.");
+ }
goto error;
}
DBG2("UST app event %s created successfully for pid:%d",
ua_event->attr.name, app->pid);
- health_code_update(&health_thread_cmd);
+ health_code_update();
/* Set filter if one is present. */
if (ua_event->filter) {
}
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
- /* Copy event attributes */
- memcpy(&ua_chan->attr, &uchan->attr, sizeof(ua_chan->attr));
+
+ /* Copy event attributes since the layout is different. */
+ ua_chan->attr.subbuf_size = uchan->attr.subbuf_size;
+ ua_chan->attr.num_subbuf = uchan->attr.num_subbuf;
+ ua_chan->attr.overwrite = uchan->attr.overwrite;
+ ua_chan->attr.switch_timer_interval = uchan->attr.switch_timer_interval;
+ ua_chan->attr.read_timer_interval = uchan->attr.read_timer_interval;
+ ua_chan->attr.output = uchan->attr.output;
+ /*
+ * Note that the attribute channel type is not set since the channel on the
+ * tracing registry side does not have this information.
+ */
ua_chan->enabled = uchan->enabled;
continue;
}
shadow_copy_event(ua_event, uevent);
- add_unique_ust_app_event(ua_chan->events, ua_event);
+ add_unique_ust_app_event(ua_chan, ua_event);
}
}
DBG2("Channel %s not found on shadow session copy, creating it",
uchan->name);
- ua_chan = alloc_ust_app_channel(uchan->name, &uchan->attr);
+ ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr);
if (ua_chan == NULL) {
/* malloc failed FIXME: Might want to do handle ENOMEM .. */
continue;
}
-
shadow_copy_channel(ua_chan, uchan);
+ /*
+ * The concept of metadata channel does not exist on the tracing
+ * registry side of the session daemon so this can only be a per CPU
+ * channel and not metadata.
+ */
+ ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
+
lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
}
}
assert(app);
assert(ua_sess_ptr);
- health_code_update(&health_thread_cmd);
+ health_code_update();
ua_sess = lookup_session_by_app(usess, app);
if (ua_sess == NULL) {
DBG2("UST app pid: %d session id %d not found, creating it",
app->pid, usess->id);
- ua_sess = alloc_ust_app_session();
+ ua_sess = alloc_ust_app_session(app);
if (ua_sess == NULL) {
/* Only malloc can failed so something is really wrong */
ret = -ENOMEM;
created = 1;
}
- health_code_update(&health_thread_cmd);
+ health_code_update();
if (ua_sess->handle == -1) {
ret = ustctl_create_session(app->sock);
if (ret < 0) {
- ERR("Creating session for app pid %d", app->pid);
- delete_ust_app_session(-1, ua_sess);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("Creating session for app pid %d with ret %d",
+ app->pid, ret);
+ } else {
+ DBG("UST app creating session failed. Application is dead");
+ }
+ delete_ust_app_session(-1, ua_sess, app);
if (ret != -ENOMEM) {
/*
* Tracer is probably gone or got an internal error so let's
DBG2("UST app session created successfully with handle %d", ret);
}
+ /*
+ * Assign consumer if not already set. For one application, there is only
+ * one possible consumer has of now.
+ */
+ if (!ua_sess->consumer) {
+ ua_sess->consumer = usess->consumer;
+ }
+
*ua_sess_ptr = ua_sess;
if (is_created) {
*is_created = created;
}
+
/* Everything went well. */
ret = 0;
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
/*
* Create a context for the channel on the tracer.
+ *
+ * Called with UST app session lock held.
*/
static
int create_ust_app_channel_context(struct ust_app_session *ua_sess,
/*
* Enable on the tracer side a ust app event for the session and channel.
+ *
+ * Called with UST app session lock held.
*/
static
int enable_ust_app_event(struct ust_app_session *ua_sess,
/*
* Create UST app channel and create it on the tracer. Set ua_chanp of the
* newly created channel if not NULL.
+ *
+ * Called with UST app session lock held.
*/
static int create_ust_app_channel(struct ust_app_session *ua_sess,
struct ltt_ust_channel *uchan, struct ust_app *app,
+ struct consumer_output *consumer, enum lttng_ust_chan_type type,
struct ust_app_channel **ua_chanp)
{
int ret = 0;
goto end;
}
- ua_chan = alloc_ust_app_channel(uchan->name, &uchan->attr);
+ ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr);
if (ua_chan == NULL) {
/* Only malloc can fail here */
ret = -ENOMEM;
}
shadow_copy_channel(ua_chan, uchan);
- ret = create_ust_channel(app, ua_sess, ua_chan);
+ /* Set channel type. */
+ ua_chan->attr.type = type;
+
+ ret = create_ust_channel(app, ua_sess, ua_chan, consumer);
if (ret < 0) {
- /* Not found previously means that it does not exist on the tracer */
- assert(ret != -LTTNG_UST_ERR_EXIST);
goto error;
}
- /* Only add the channel if successful on the tracer side. */
- lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
-
DBG2("UST app create channel %s for PID %d completed", ua_chan->name,
app->pid);
+ /* Only add the channel if successful on the tracer side. */
+ lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
+
end:
if (ua_chanp) {
*ua_chanp = ua_chan;
return 0;
error:
- delete_ust_app_channel(-1, ua_chan);
+ delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app);
return ret;
}
/*
* Create UST app event and create it on the tracer side.
+ *
+ * Called with ust app session mutex held.
*/
static
int create_ust_app_event(struct ust_app_session *ua_sess,
goto error;
}
- add_unique_ust_app_event(ua_chan->events, ua_event);
+ add_unique_ust_app_event(ua_chan, ua_event);
DBG2("UST app create event %s for PID %d completed", ua_event->name,
app->pid);
/*
* Create UST metadata and open it on the tracer side.
+ *
+ * Called with UST app session lock held.
*/
static int create_ust_app_metadata(struct ust_app_session *ua_sess,
- char *pathname, struct ust_app *app)
+ struct ust_app *app, struct consumer_output *consumer)
{
int ret = 0;
+ struct ust_app_channel *metadata;
+ struct consumer_socket *socket;
- if (ua_sess->metadata == NULL) {
- /* Allocate UST metadata */
- ua_sess->metadata = trace_ust_create_metadata(pathname);
- if (ua_sess->metadata == NULL) {
- /* malloc() failed */
- goto error;
- }
-
- ret = open_ust_metadata(app, ua_sess);
- if (ret < 0) {
- DBG3("Opening metadata failed. Cleaning up memory");
+ assert(ua_sess);
+ assert(app);
+ assert(consumer);
- /* Cleanup failed metadata struct */
- free(ua_sess->metadata);
- /*
- * This is very important because delete_ust_app_session check if
- * the pointer is null or not in order to delete the metadata.
- */
- ua_sess->metadata = NULL;
- goto error;
- }
+ if (ua_sess->metadata) {
+ /* Already exist. Return success. */
+ goto end;
+ }
- DBG2("UST metadata opened for app pid %d", app->pid);
+ /* Allocate UST metadata */
+ metadata = alloc_ust_app_channel(DEFAULT_METADATA_NAME, ua_sess, NULL);
+ if (!metadata) {
+ /* malloc() failed */
+ ret = -ENOMEM;
+ goto error;
}
- /* Open UST metadata stream */
- if (ua_sess->metadata->stream_obj == NULL) {
- ret = create_ust_metadata_stream(app, ua_sess);
- if (ret < 0) {
- goto error;
- }
+ /* Set default attributes for metadata. */
+ metadata->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
+ metadata->attr.subbuf_size = default_get_metadata_subbuf_size();
+ metadata->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
+ metadata->attr.switch_timer_interval = DEFAULT_UST_CHANNEL_SWITCH_TIMER;
+ metadata->attr.read_timer_interval = DEFAULT_UST_CHANNEL_READ_TIMER;
+ metadata->attr.output = LTTNG_UST_MMAP;
+ metadata->attr.type = LTTNG_UST_CHAN_METADATA;
- ret = snprintf(ua_sess->metadata->pathname, PATH_MAX,
- "%s/metadata", ua_sess->path);
- if (ret < 0) {
- PERROR("asprintf UST create stream");
- goto error;
- }
+ /* Get the right consumer socket for the application. */
+ socket = find_consumer_socket_by_bitness(app->bits_per_long, consumer);
+ if (!socket) {
+ ret = -EINVAL;
+ goto error_consumer;
+ }
- DBG2("UST metadata stream object created for app pid %d",
- app->pid);
- } else {
- ERR("Attempting to create stream without metadata opened");
- goto error;
+ /*
+ * Ask the metadata channel creation to the consumer. The metadata object
+ * will be created by the consumer and kept their. However, the stream is
+ * never added or monitored until we do a first push metadata to the
+ * consumer.
+ */
+ ret = ust_consumer_ask_channel(ua_sess, metadata, consumer, socket);
+ if (ret < 0) {
+ goto error_consumer;
}
- return 0;
+ /*
+ * The setup command will make the metadata stream be sent to the relayd,
+ * if applicable, and the thread managing the metadatas. This is important
+ * because after this point, if an error occurs, the only way the stream
+ * can be deleted is to be monitored in the consumer.
+ */
+ ret = ust_consumer_setup_metadata(socket, metadata);
+ if (ret < 0) {
+ goto error_consumer;
+ }
+ ua_sess->metadata = metadata;
+
+ DBG2("UST metadata created for app pid %d", app->pid);
+
+end:
+ return 0;
+error_consumer:
+ delete_ust_app_channel(-1, metadata, app);
error:
- return -1;
+ return ret;
}
/*
}
/*
- * Return ust app pointer or NULL if not found.
+ * Return ust app pointer or NULL if not found. RCU read side lock MUST be
+ * acquired before calling this function.
*/
struct ust_app *ust_app_find_by_pid(pid_t pid)
{
+ struct ust_app *app = NULL;
struct lttng_ht_node_ulong *node;
struct lttng_ht_iter iter;
- rcu_read_lock();
lttng_ht_lookup(ust_app_ht, (void *)((unsigned long) pid), &iter);
node = lttng_ht_iter_get_node_ulong(&iter);
if (node == NULL) {
DBG2("UST app no found with pid %d", pid);
goto error;
}
- rcu_read_unlock();
DBG2("Found UST app by pid %d", pid);
- return caa_container_of(node, struct ust_app, pid_n);
+ app = caa_container_of(node, struct ust_app, pid_n);
error:
- rcu_read_unlock();
- return NULL;
+ return app;
}
/*
- * Using pid and uid (of the app), allocate a new ust_app struct and
- * add it to the global traceable app list.
+ * Allocate and init an UST app object using the registration information and
+ * the command socket. This is called when the command socket connects to the
+ * session daemon.
*
- * On success, return 0, else return malloc -ENOMEM, or -EINVAL if app
- * bitness is not supported.
+ * The object is returned on success or else NULL.
*/
-int ust_app_register(struct ust_register_msg *msg, int sock)
+struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
{
- struct ust_app *lta;
- int ret;
+ struct ust_app *lta = NULL;
+
+ assert(msg);
+ assert(sock >= 0);
+
+ DBG3("UST app creating application for socket %d", sock);
if ((msg->bits_per_long == 64 &&
(uatomic_read(&ust_consumerd64_fd) == -EINVAL))
|| (msg->bits_per_long == 32 &&
(uatomic_read(&ust_consumerd32_fd) == -EINVAL))) {
ERR("Registration failed: application \"%s\" (pid: %d) has "
- "%d-bit long, but no consumerd for this long size is available.\n",
- msg->name, msg->pid, msg->bits_per_long);
- ret = close(sock);
- if (ret) {
- PERROR("close");
- }
- lttng_fd_put(LTTNG_FD_APPS, 1);
- return -EINVAL;
- }
- if (msg->major != LTTNG_UST_COMM_MAJOR) {
- ERR("Registration failed: application \"%s\" (pid: %d) has "
- "communication protocol version %u.%u, but sessiond supports 2.x.\n",
- msg->name, msg->pid, msg->major, msg->minor);
- ret = close(sock);
- if (ret) {
- PERROR("close");
- }
- lttng_fd_put(LTTNG_FD_APPS, 1);
- return -EINVAL;
+ "%d-bit long, but no consumerd for this size is available.\n",
+ msg->name, msg->pid, msg->bits_per_long);
+ goto error;
}
+
lta = zmalloc(sizeof(struct ust_app));
if (lta == NULL) {
PERROR("malloc");
- return -ENOMEM;
+ goto error;
}
lta->ppid = msg->ppid;
lta->uid = msg->uid;
lta->gid = msg->gid;
- lta->compatible = 0; /* Not compatible until proven */
+
lta->bits_per_long = msg->bits_per_long;
+ lta->uint8_t_alignment = msg->uint8_t_alignment;
+ lta->uint16_t_alignment = msg->uint16_t_alignment;
+ lta->uint32_t_alignment = msg->uint32_t_alignment;
+ lta->uint64_t_alignment = msg->uint64_t_alignment;
+ lta->long_alignment = msg->long_alignment;
+ lta->byte_order = msg->byte_order;
+
lta->v_major = msg->major;
lta->v_minor = msg->minor;
- strncpy(lta->name, msg->name, sizeof(lta->name));
- lta->name[16] = '\0';
lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
+ lta->ust_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
+ lta->notify_sock = -1;
+
+ /* Copy name and make sure it's NULL terminated. */
+ strncpy(lta->name, msg->name, sizeof(lta->name));
+ lta->name[UST_APP_PROCNAME_LEN] = '\0';
+
+ /*
+ * Before this can be called, when receiving the registration information,
+ * the application compatibility is checked. So, at this point, the
+ * application can work with this session daemon.
+ */
+ lta->compatible = 1;
lta->pid = msg->pid;
- lttng_ht_node_init_ulong(<a->pid_n, (unsigned long)lta->pid);
+ lttng_ht_node_init_ulong(<a->pid_n, (unsigned long) lta->pid);
lta->sock = sock;
- lttng_ht_node_init_ulong(<a->sock_n, (unsigned long)lta->sock);
+ lttng_ht_node_init_ulong(<a->sock_n, (unsigned long) lta->sock);
CDS_INIT_LIST_HEAD(<a->teardown_head);
+error:
+ return lta;
+}
+
+/*
+ * For a given application object, add it to every hash table.
+ */
+void ust_app_add(struct ust_app *app)
+{
+ assert(app);
+ assert(app->notify_sock >= 0);
+
rcu_read_lock();
/*
* On a re-registration, we want to kick out the previous registration of
* that pid
*/
- lttng_ht_add_replace_ulong(ust_app_ht, <a->pid_n);
+ lttng_ht_add_replace_ulong(ust_app_ht, &app->pid_n);
/*
* The socket _should_ be unique until _we_ call close. So, a add_unique
* for the ust_app_ht_by_sock is used which asserts fail if the entry was
* already in the table.
*/
- lttng_ht_add_unique_ulong(ust_app_ht_by_sock, <a->sock_n);
+ lttng_ht_add_unique_ulong(ust_app_ht_by_sock, &app->sock_n);
+
+ /* Add application to the notify socket hash table. */
+ lttng_ht_node_init_ulong(&app->notify_sock_n, app->notify_sock);
+ lttng_ht_add_unique_ulong(ust_app_ht_by_notify_sock, &app->notify_sock_n);
+
+ DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s "
+ "notify_sock:%d (version %d.%d)", app->pid, app->ppid, app->uid,
+ app->gid, app->sock, app->name, app->notify_sock, app->v_major,
+ app->v_minor);
rcu_read_unlock();
+}
- DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s"
- " (version %d.%d)", lta->pid, lta->ppid, lta->uid, lta->gid,
- lta->sock, lta->name, lta->v_major, lta->v_minor);
+/*
+ * Set the application version into the object.
+ *
+ * Return 0 on success else a negative value either an errno code or a
+ * LTTng-UST error code.
+ */
+int ust_app_version(struct ust_app *app)
+{
+ int ret;
- return 0;
+ assert(app);
+
+ ret = ustctl_tracer_version(app->sock, &app->version);
+ if (ret < 0) {
+ if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
+ ERR("UST app %d verson failed with ret %d", app->sock, ret);
+ } else {
+ DBG3("UST app %d verion failed. Application is dead", app->sock);
+ }
+ }
+
+ return ret;
}
/*
/* Get the node reference for a call_rcu */
lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
node = lttng_ht_iter_get_node_ulong(&iter);
- if (node == NULL) {
- ERR("Unable to find app by sock %d", sock);
- goto error;
- }
+ assert(node);
lta = caa_container_of(node, struct ust_app, sock_n);
-
DBG("PID %d unregistering with sock %d", lta->pid, sock);
/* Remove application from PID hash table */
ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
assert(!ret);
- /* Assign second node for deletion */
- iter.iter.node = <a->pid_n.node;
+ /*
+ * Remove application from notify hash table. The thread handling the
+ * notify socket could have deleted the node so ignore on error because
+ * either way it's valid. The close of that socket is handled by the other
+ * thread.
+ */
+ iter.iter.node = <a->notify_sock_n.node;
+ (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
/*
* Ignore return value since the node might have been removed before by an
* add replace during app registration because the PID can be reassigned by
* the OS.
*/
+ iter.iter.node = <a->pid_n.node;
ret = lttng_ht_del(ust_app_ht, &iter);
if (ret) {
DBG3("Unregister app by PID %d failed. This can happen on pid reuse",
* Add session to list for teardown. This is safe since at this point we
* are the only one using this list.
*/
+ pthread_mutex_lock(&ua_sess->lock);
+
+ /*
+ * Normally, this is done in the delete session process which is
+ * executed in the call rcu below. However, upon registration we can't
+ * afford to wait for the grace period before pushing data or else the
+ * data pending feature can race between the unregistration and stop
+ * command where the data pending command is sent *before* the grace
+ * period ended.
+ *
+ * The close metadata below nullifies the metadata pointer in the
+ * session so the delete session will NOT push/close a second time.
+ */
+ (void) push_metadata(lta, ua_sess);
+ (void) close_metadata(lta, ua_sess);
+
cds_list_add(&ua_sess->teardown_node, <a->teardown_head);
+ pthread_mutex_unlock(&ua_sess->lock);
}
/* Free memory */
call_rcu(<a->pid_n.head, delete_ust_app_rcu);
-error:
rcu_read_unlock();
return;
}
cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
struct lttng_ust_tracepoint_iter uiter;
- health_code_update(&health_thread_cmd);
+ health_code_update();
if (!app->compatible) {
/*
}
handle = ustctl_tracepoint_list(app->sock);
if (handle < 0) {
- ERR("UST app list events getting handle failed for app pid %d",
- app->pid);
+ if (handle != -EPIPE && handle != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app list events getting handle failed for app pid %d",
+ app->pid);
+ }
continue;
}
while ((ret = ustctl_tracepoint_list_get(app->sock, handle,
&uiter)) != -LTTNG_UST_ERR_NOENT) {
- health_code_update(&health_thread_cmd);
+ /* Handle ustctl error. */
+ if (ret < 0) {
+ free(tmp_event);
+ if (ret != -LTTNG_UST_ERR_EXITING || ret != -EPIPE) {
+ ERR("UST app tp list get failed for app %d with ret %d",
+ app->sock, ret);
+ } else {
+ DBG3("UST app tp list get failed. Application is dead");
+ }
+ goto rcu_error;
+ }
+
+ health_code_update();
if (count >= nbmem) {
/* In case the realloc fails, we free the memory */
void *ptr;
rcu_error:
rcu_read_unlock();
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
struct lttng_ust_field_iter uiter;
- health_code_update(&health_thread_cmd);
+ health_code_update();
if (!app->compatible) {
/*
}
handle = ustctl_tracepoint_field_list(app->sock);
if (handle < 0) {
- ERR("UST app list event fields getting handle failed for app pid %d",
- app->pid);
+ if (handle != -EPIPE && handle != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app list field getting handle failed for app pid %d",
+ app->pid);
+ }
continue;
}
while ((ret = ustctl_tracepoint_field_list_get(app->sock, handle,
&uiter)) != -LTTNG_UST_ERR_NOENT) {
- health_code_update(&health_thread_cmd);
+ /* Handle ustctl error. */
+ if (ret < 0) {
+ free(tmp_event);
+ if (ret != -LTTNG_UST_ERR_EXITING || ret != -EPIPE) {
+ ERR("UST app tp list field failed for app %d with ret %d",
+ app->sock, ret);
+ } else {
+ DBG3("UST app tp list field failed. Application is dead");
+ }
+ goto rcu_error;
+ }
+
+ health_code_update();
if (count >= nbmem) {
/* In case the realloc fails, we free the memory */
void *ptr;
rcu_error:
rcu_read_unlock();
error:
- health_code_update(&health_thread_cmd);
+ health_code_update();
return ret;
}
assert(!ret);
}
+ /* Cleanup notify socket hash table */
+ cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app,
+ notify_sock_n.node) {
+ ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
+ assert(!ret);
+ }
+
/* Destroy is done only when the ht is empty */
lttng_ht_destroy(ust_app_ht);
lttng_ht_destroy(ust_app_ht_by_sock);
+ lttng_ht_destroy(ust_app_ht_by_notify_sock);
rcu_read_unlock();
}
{
ust_app_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
ust_app_ht_by_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
+ ust_app_ht_by_notify_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
}
/*
}
assert(ua_sess);
+ pthread_mutex_lock(&ua_sess->lock);
/* Create channel onto application. We don't need the chan ref. */
- ret = create_ust_app_channel(ua_sess, uchan, app, NULL);
+ ret = create_ust_app_channel(ua_sess, uchan, app, usess->consumer,
+ LTTNG_UST_CHAN_PER_CPU, NULL);
+ pthread_mutex_unlock(&ua_sess->lock);
if (ret < 0) {
if (ret == -ENOMEM) {
/* No more memory is a fatal error. Stop right now. */
}
/* Cleanup the created session if it's the case. */
if (created) {
- delete_ust_app_session(app->sock, ua_sess);
+ destroy_app_session(app, ua_sess);
}
}
}
continue;
}
+ pthread_mutex_lock(&ua_sess->lock);
+
/* Lookup channel in the ust app session */
lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
if (ua_event == NULL) {
DBG3("UST app enable event %s not found for app PID %d."
"Skipping app", uevent->attr.name, app->pid);
- continue;
+ goto next_app;
}
ret = enable_ust_app_event(ua_sess, ua_event, app);
if (ret < 0) {
+ pthread_mutex_unlock(&ua_sess->lock);
goto error;
}
+ next_app:
+ pthread_mutex_unlock(&ua_sess->lock);
}
error:
continue;
}
+ pthread_mutex_lock(&ua_sess->lock);
/* Lookup channel in the ust app session */
lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
+ pthread_mutex_unlock(&ua_sess->lock);
if (ret < 0) {
if (ret != -LTTNG_UST_ERR_EXIST) {
/* Possible value at this point: -ENOMEM. If so, we stop! */
int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
{
int ret = 0;
- struct lttng_ht_iter iter;
struct ust_app_session *ua_sess;
- struct ust_app_channel *ua_chan;
- struct ust_app_stream *ustream;
- struct consumer_socket *socket;
DBG("Starting tracing for ust app pid %d", app->pid);
goto end;
}
+ pthread_mutex_lock(&ua_sess->lock);
+
/* Upon restart, we skip the setup, already done */
if (ua_sess->started) {
goto skip_setup;
if (ret < 0) {
if (ret != -EEXIST) {
ERR("Trace directory creation error");
- ret = -1;
- goto error_rcu_unlock;
+ goto error_unlock;
}
}
}
- ret = create_ust_app_metadata(ua_sess, usess->pathname, app);
+ /* Create the metadata for the application. */
+ ret = create_ust_app_metadata(ua_sess, app, usess->consumer);
if (ret < 0) {
- ret = LTTNG_ERR_UST_META_FAIL;
- goto error_rcu_unlock;
+ goto error_unlock;
}
- /* For each channel */
- cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
- node.node) {
- /* Create all streams */
- while (1) {
- /* Create UST stream */
- ustream = alloc_ust_app_stream();
- if (ustream == NULL) {
- goto error_rcu_unlock;
- }
-
- health_code_update(&health_thread_cmd);
-
- ret = create_ust_stream(app, ua_chan, ustream);
- if (ret < 0) {
- /* Free unused memory after this point. */
- free(ustream);
- if (ret == -LTTNG_UST_ERR_NOENT) {
- /* Got all streams. Continue normal execution. */
- break;
- }
- /* Error at this point. Stop everything. */
- ret = LTTNG_ERR_UST_STREAM_FAIL;
- goto error_rcu_unlock;
- }
-
- health_code_update(&health_thread_cmd);
-
- /* Order is important this is why a list is used. */
- cds_list_add_tail(&ustream->list, &ua_chan->streams.head);
- ua_chan->streams.count++;
-
- DBG2("UST stream %d ready (handle: %d)", ua_chan->streams.count,
- ustream->handle);
- }
-
- health_code_update(&health_thread_cmd);
- }
-
- switch (app->bits_per_long) {
- case 64:
- socket = consumer_find_socket(uatomic_read(&ust_consumerd64_fd),
- usess->consumer);
- if (socket == NULL) {
- goto skip_setup;
- }
- break;
- case 32:
- socket = consumer_find_socket(uatomic_read(&ust_consumerd32_fd),
- usess->consumer);
- if (socket == NULL) {
- goto skip_setup;
- }
- break;
- default:
- ret = -EINVAL;
- goto error_rcu_unlock;
- }
-
- /* Setup UST consumer socket and send fds to it */
- ret = ust_consumer_send_session(ua_sess, usess->consumer, socket);
- if (ret < 0) {
- goto error_rcu_unlock;
- }
-
- health_code_update(&health_thread_cmd);
+ health_code_update();
skip_setup:
/* This start the UST tracing */
ret = ustctl_start_session(app->sock, ua_sess->handle);
if (ret < 0) {
- ERR("Error starting tracing for app pid: %d (ret: %d)", app->pid, ret);
- goto error_rcu_unlock;
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("Error starting tracing for app pid: %d (ret: %d)",
+ app->pid, ret);
+ } else {
+ DBG("UST app start session failed. Application is dead.");
+ }
+ goto error_unlock;
}
/* Indicate that the session has been started once */
ua_sess->started = 1;
- health_code_update(&health_thread_cmd);
+ pthread_mutex_unlock(&ua_sess->lock);
+
+ health_code_update();
/* Quiescent wait after starting trace */
- ustctl_wait_quiescent(app->sock);
+ ret = ustctl_wait_quiescent(app->sock);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app wait quiescent failed for app pid %d ret %d",
+ app->pid, ret);
+ }
end:
rcu_read_unlock();
- health_code_update(&health_thread_cmd);
+ health_code_update();
return 0;
-error_rcu_unlock:
+error_unlock:
+ pthread_mutex_unlock(&ua_sess->lock);
rcu_read_unlock();
- health_code_update(&health_thread_cmd);
+ health_code_update();
return -1;
}
rcu_read_lock();
if (!app->compatible) {
- goto end;
+ goto end_no_session;
}
ua_sess = lookup_session_by_app(usess, app);
if (ua_sess == NULL) {
- goto end;
+ goto end_no_session;
}
+ pthread_mutex_lock(&ua_sess->lock);
+
/*
* If started = 0, it means that stop trace has been called for a session
* that was never started. It's possible since we can have a fail start
goto error_rcu_unlock;
}
- health_code_update(&health_thread_cmd);
+ health_code_update();
/* This inhibits UST tracing */
ret = ustctl_stop_session(app->sock, ua_sess->handle);
if (ret < 0) {
- ERR("Error stopping tracing for app pid: %d (ret: %d)", app->pid, ret);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("Error stopping tracing for app pid: %d (ret: %d)",
+ app->pid, ret);
+ } else {
+ DBG("UST app stop session failed. Application is dead.");
+ }
goto error_rcu_unlock;
}
- health_code_update(&health_thread_cmd);
+ health_code_update();
/* Quiescent wait after stopping trace */
- ustctl_wait_quiescent(app->sock);
+ ret = ustctl_wait_quiescent(app->sock);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app wait quiescent failed for app pid %d ret %d",
+ app->pid, ret);
+ }
- health_code_update(&health_thread_cmd);
+ health_code_update();
/* Flushing buffers */
cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
node.node) {
- health_code_update(&health_thread_cmd);
+ health_code_update();
+ assert(ua_chan->is_sent);
ret = ustctl_sock_flush_buffer(app->sock, ua_chan->obj);
if (ret < 0) {
- ERR("UST app PID %d channel %s flush failed with ret %d",
- app->pid, ua_chan->name, ret);
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app PID %d channel %s flush failed with ret %d",
+ app->pid, ua_chan->name, ret);
+ } else {
+ DBG3("UST app failed to flush %s. Application is dead.",
+ ua_chan->name);
+ /* No need to continue. */
+ break;
+ }
/* Continuing flushing all buffers */
continue;
}
}
- health_code_update(&health_thread_cmd);
+ health_code_update();
- /* Flush all buffers before stopping */
- ret = ustctl_sock_flush_buffer(app->sock, ua_sess->metadata->obj);
+ ret = push_metadata(app, ua_sess);
if (ret < 0) {
- ERR("UST app PID %d metadata flush failed with ret %d", app->pid,
- ret);
+ goto error_rcu_unlock;
}
-end:
+ pthread_mutex_unlock(&ua_sess->lock);
+end_no_session:
rcu_read_unlock();
- health_code_update(&health_thread_cmd);
+ health_code_update();
return 0;
error_rcu_unlock:
+ pthread_mutex_unlock(&ua_sess->lock);
rcu_read_unlock();
- health_code_update(&health_thread_cmd);
+ health_code_update();
return -1;
}
*/
static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
{
+ int ret;
struct ust_app_session *ua_sess;
- struct lttng_ust_object_data obj;
struct lttng_ht_iter iter;
struct lttng_ht_node_ulong *node;
- int ret;
DBG("Destroy tracing for ust app pid %d", app->pid);
goto end;
}
ua_sess = caa_container_of(node, struct ust_app_session, node);
- ret = lttng_ht_del(app->sessions, &iter);
- if (ret) {
- /* Already scheduled for teardown. */
- goto end;
- }
- obj.handle = ua_sess->handle;
- obj.shm_fd = -1;
- obj.wait_fd = -1;
- obj.memory_map_size = 0;
- health_code_update(&health_thread_cmd);
- ustctl_release_object(app->sock, &obj);
+ health_code_update();
+ destroy_app_session(app, ua_sess);
- health_code_update(&health_thread_cmd);
- delete_ust_app_session(app->sock, ua_sess);
+ health_code_update();
/* Quiescent wait after stopping trace */
- ustctl_wait_quiescent(app->sock);
-
+ ret = ustctl_wait_quiescent(app->sock);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app wait quiescent failed for app pid %d ret %d",
+ app->pid, ret);
+ }
end:
rcu_read_unlock();
- health_code_update(&health_thread_cmd);
+ health_code_update();
return 0;
}
cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
ret = ust_app_stop_trace(usess, app);
if (ret < 0) {
+ ERR("UST app stop trace failed with ret %d", ret);
/* Continue to next apps even on error */
continue;
}
struct ust_app_ctx *ua_ctx;
assert(usess);
+ assert(sock >= 0);
DBG2("UST app global update for app sock %d for session id %d", sock,
usess->id);
app = find_app_by_sock(sock);
if (app == NULL) {
- ERR("Failed to update app sock %d", sock);
+ /*
+ * Application can be unregistered before so this is possible hence
+ * simply stopping the update.
+ */
+ DBG3("UST app update failed to find app sock %d", sock);
goto error;
}
}
assert(ua_sess);
+ pthread_mutex_lock(&ua_sess->lock);
+
/*
- * We can iterate safely here over all UST app session sicne the create ust
+ * We can iterate safely here over all UST app session since the create ust
* app session above made a shadow copy of the UST global domain from the
* ltt ust session.
*/
cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
node.node) {
- ret = create_ust_channel(app, ua_sess, ua_chan);
+ ret = create_ust_channel(app, ua_sess, ua_chan, usess->consumer);
if (ret < 0) {
- /* FIXME: Should we quit here or continue... */
- continue;
+ /*
+ * Stop everything. On error, the application failed, no more file
+ * descriptor are available or ENOMEM so stopping here is the only
+ * thing we can do for now.
+ */
+ goto error_unlock;
}
cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter_ctx.iter, ua_ctx,
node.node) {
ret = create_ust_channel_context(ua_chan, ua_ctx, app);
if (ret < 0) {
- /* FIXME: Should we quit here or continue... */
- continue;
+ goto error_unlock;
}
}
node.node) {
ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
if (ret < 0) {
- /* FIXME: Should we quit here or continue... */
- continue;
+ goto error_unlock;
}
}
}
+ pthread_mutex_unlock(&ua_sess->lock);
+
if (usess->start_trace) {
ret = ust_app_start_trace(usess, app);
if (ret < 0) {
DBG2("UST trace started for app pid %d", app->pid);
}
+ /* Everything went well at this point. */
+ rcu_read_unlock();
+ return;
+
+error_unlock:
+ pthread_mutex_unlock(&ua_sess->lock);
error:
+ if (ua_sess) {
+ destroy_app_session(app, ua_sess);
+ }
rcu_read_unlock();
return;
}
continue;
}
+ pthread_mutex_lock(&ua_sess->lock);
/* Lookup channel in the ust app session */
lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
if (ua_chan_node == NULL) {
- continue;
+ goto next_app;
}
ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
node);
-
ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app);
if (ret < 0) {
- continue;
+ goto next_app;
}
+ next_app:
+ pthread_mutex_unlock(&ua_sess->lock);
}
rcu_read_unlock();
if (app == NULL) {
ERR("UST app enable event per PID %d not found", pid);
ret = -1;
- goto error;
+ goto end;
}
if (!app->compatible) {
ret = 0;
- goto error;
+ goto end;
}
ua_sess = lookup_session_by_app(usess, app);
if (!ua_sess) {
/* The application has problem or is probably dead. */
- goto error;
+ ret = 0;
+ goto end;
}
+ pthread_mutex_lock(&ua_sess->lock);
/* Lookup channel in the ust app session */
lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
ua_chan_node = lttng_ht_iter_get_node_str(&iter);
if (ua_event == NULL) {
ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
if (ret < 0) {
- goto error;
+ goto end_unlock;
}
} else {
ret = enable_ust_app_event(ua_sess, ua_event, app);
if (ret < 0) {
- goto error;
+ goto end_unlock;
}
}
-error:
+end_unlock:
+ pthread_mutex_unlock(&ua_sess->lock);
+end:
rcu_read_unlock();
return ret;
}
return ret;
}
-/*
- * Validate version of UST apps and set the compatible bit.
- */
-int ust_app_validate_version(int sock)
-{
- int ret;
- struct ust_app *app;
-
- rcu_read_lock();
-
- app = find_app_by_sock(sock);
- assert(app);
-
- health_code_update(&health_thread_cmd);
-
- ret = ustctl_tracer_version(sock, &app->version);
- if (ret < 0) {
- goto error;
- }
-
- /* Validate version */
- if (app->version.major != UST_APP_MAJOR_VERSION) {
- goto error;
- }
-
- DBG2("UST app PID %d is compatible with internal major version %d "
- "(supporting == %d)", app->pid, app->version.major,
- UST_APP_MAJOR_VERSION);
- app->compatible = 1;
- rcu_read_unlock();
- health_code_update(&health_thread_cmd);
- return 0;
-
-error:
- DBG2("UST app PID %d is not compatible with internal major version %d "
- "(supporting == %d)", app->pid, app->version.major,
- UST_APP_MAJOR_VERSION);
- app->compatible = 0;
- rcu_read_unlock();
- health_code_update(&health_thread_cmd);
- return -1;
-}
-
/*
* Calibrate registered applications.
*/
continue;
}
- health_code_update(&health_thread_cmd);
+ health_code_update();
ret = ustctl_calibrate(app->sock, calibrate);
if (ret < 0) {
ret = 0;
break;
default:
- /* TODO: Report error to user */
DBG2("Calibrate app PID %d returned with error %d",
app->pid, ret);
break;
rcu_read_unlock();
- health_code_update(&health_thread_cmd);
+ health_code_update();
+
+ return ret;
+}
+
+/*
+ * Receive registration and populate the given msg structure.
+ *
+ * On success return 0 else a negative value returned by the ustctl call.
+ */
+int ust_app_recv_registration(int sock, struct ust_register_msg *msg)
+{
+ int ret;
+ uint32_t pid, ppid, uid, gid;
+
+ assert(msg);
+
+ ret = ustctl_recv_reg_msg(sock, &msg->type, &msg->major, &msg->minor,
+ &pid, &ppid, &uid, &gid,
+ &msg->bits_per_long,
+ &msg->uint8_t_alignment,
+ &msg->uint16_t_alignment,
+ &msg->uint32_t_alignment,
+ &msg->uint64_t_alignment,
+ &msg->long_alignment,
+ &msg->byte_order,
+ msg->name);
+ if (ret < 0) {
+ switch (-ret) {
+ case EPIPE:
+ case ECONNRESET:
+ case LTTNG_UST_ERR_EXITING:
+ DBG3("UST app recv reg message failed. Application died");
+ break;
+ case LTTNG_UST_ERR_UNSUP_MAJOR:
+ ERR("UST app recv reg unsupported version %d.%d. Supporting %d.%d",
+ msg->major, msg->minor, LTTNG_UST_ABI_MAJOR_VERSION,
+ LTTNG_UST_ABI_MINOR_VERSION);
+ break;
+ default:
+ ERR("UST app recv reg message failed with ret %d", ret);
+ break;
+ }
+ goto error;
+ }
+ msg->pid = (pid_t) pid;
+ msg->ppid = (pid_t) ppid;
+ msg->uid = (uid_t) uid;
+ msg->gid = (gid_t) gid;
+
+error:
+ return ret;
+}
+
+/*
+ * Return a ust app channel object using the application object and the channel
+ * object descriptor has a key. If not found, NULL is returned. A RCU read side
+ * lock MUST be acquired before calling this function.
+ */
+static struct ust_app_channel *find_channel_by_objd(struct ust_app *app,
+ int objd)
+{
+ struct lttng_ht_node_ulong *node;
+ struct lttng_ht_iter iter;
+ struct ust_app_channel *ua_chan = NULL;
+
+ assert(app);
+
+ lttng_ht_lookup(app->ust_objd, (void *)((unsigned long) objd), &iter);
+ node = lttng_ht_iter_get_node_ulong(&iter);
+ if (node == NULL) {
+ DBG2("UST app channel find by objd %d not found", objd);
+ goto error;
+ }
+
+ ua_chan = caa_container_of(node, struct ust_app_channel, ust_objd_node);
+
+error:
+ return ua_chan;
+}
+
+/*
+ * Reply to a register channel notification from an application on the notify
+ * socket. The channel metadata is also created.
+ *
+ * The session UST registry lock is acquired in this function.
+ *
+ * On success 0 is returned else a negative value.
+ */
+static int reply_ust_register_channel(int sock, int sobjd, int cobjd,
+ size_t nr_fields, struct ustctl_field *fields)
+{
+ int ret, ret_code = 0;
+ uint32_t chan_id, reg_count;
+ enum ustctl_channel_header type;
+ struct ust_app *app;
+ struct ust_app_channel *ua_chan;
+ struct ust_app_session *ua_sess;
+
+ rcu_read_lock();
+
+ /* Lookup application. If not found, there is a code flow error. */
+ app = find_app_by_notify_sock(sock);
+ if (!app) {
+ DBG("Application socket %d is being teardown. Abort event notify",
+ sock);
+ ret = 0;
+ goto error_rcu_unlock;
+ }
+
+ /* Lookup channel by UST object descriptor. Should always be found. */
+ ua_chan = find_channel_by_objd(app, cobjd);
+ assert(ua_chan);
+ assert(ua_chan->session);
+ ua_sess = ua_chan->session;
+ assert(ua_sess);
+
+ pthread_mutex_lock(&ua_sess->registry.lock);
+
+ if (ust_registry_is_max_id(ua_chan->session->registry.used_channel_id)) {
+ ret_code = -1;
+ chan_id = -1U;
+ type = -1;
+ goto reply;
+ }
+
+ /* Don't assign ID to metadata. */
+ if (ua_chan->attr.type == LTTNG_UST_CHAN_METADATA) {
+ chan_id = -1U;
+ } else {
+ chan_id = ust_registry_get_next_chan_id(&ua_chan->session->registry);
+ }
+
+ reg_count = ust_registry_get_event_count(&ua_chan->registry);
+ if (reg_count < 31) {
+ type = USTCTL_CHANNEL_HEADER_COMPACT;
+ } else {
+ type = USTCTL_CHANNEL_HEADER_LARGE;
+ }
+
+ ua_chan->registry.nr_ctx_fields = nr_fields;
+ ua_chan->registry.ctx_fields = fields;
+ ua_chan->registry.chan_id = chan_id;
+ ua_chan->registry.header_type = type;
+
+ /* Append to metadata */
+ if (!ret_code) {
+ ret_code = ust_metadata_channel_statedump(&ua_chan->session->registry,
+ &ua_chan->registry);
+ if (ret_code) {
+ ERR("Error appending channel metadata (errno = %d)", ret_code);
+ goto reply;
+ }
+ }
+
+reply:
+ DBG3("UST app replying to register channel with id %u, type: %d, ret: %d",
+ chan_id, type, ret_code);
+
+ ret = ustctl_reply_register_channel(sock, chan_id, type, ret_code);
+ if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app reply channel failed with ret %d", ret);
+ } else {
+ DBG3("UST app reply channel failed. Application died");
+ }
+ goto error;
+ }
+
+error:
+ pthread_mutex_unlock(&ua_sess->registry.lock);
+error_rcu_unlock:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Add event to the UST channel registry. When the event is added to the
+ * registry, the metadata is also created. Once done, this replies to the
+ * application with the appropriate error code.
+ *
+ * The session UST registry lock is acquired in the function.
+ *
+ * On success 0 is returned else a negative value.
+ */
+static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name,
+ char *sig, size_t nr_fields, struct ustctl_field *fields, int loglevel,
+ char *model_emf_uri)
+{
+ int ret, ret_code;
+ uint32_t event_id = 0;
+ struct ust_app *app;
+ struct ust_app_channel *ua_chan;
+ struct ust_app_session *ua_sess;
+
+ rcu_read_lock();
+
+ /* Lookup application. If not found, there is a code flow error. */
+ app = find_app_by_notify_sock(sock);
+ if (!app) {
+ DBG("Application socket %d is being teardown. Abort event notify",
+ sock);
+ ret = 0;
+ goto error_rcu_unlock;
+ }
+
+ /* Lookup channel by UST object descriptor. Should always be found. */
+ ua_chan = find_channel_by_objd(app, cobjd);
+ assert(ua_chan);
+ assert(ua_chan->session);
+ ua_sess = ua_chan->session;
+
+ pthread_mutex_lock(&ua_sess->registry.lock);
+
+ ret_code = ust_registry_create_event(&ua_sess->registry,
+ &ua_chan->registry, sobjd, cobjd, name, sig, nr_fields, fields,
+ loglevel, model_emf_uri, &event_id);
+ /*
+ * The return value is returned to ustctl so in case of an error, the
+ * application can be notified. In case of an error, it's important not to
+ * return a negative error or else the application will get closed.
+ */
+ ret = ustctl_reply_register_event(sock, event_id, ret_code);
+ if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app reply event failed with ret %d", ret);
+ } else {
+ DBG3("UST app reply event failed. Application died");
+ }
+ /*
+ * No need to wipe the create event since the application socket will
+ * get close on error hence cleaning up everything by itself.
+ */
+ goto error;
+ }
+
+ DBG3("UST registry event %s has been added successfully", name);
+
+error:
+ pthread_mutex_unlock(&ua_sess->registry.lock);
+error_rcu_unlock:
+ rcu_read_unlock();
return ret;
}
+
+/*
+ * Handle application notification through the given notify socket.
+ *
+ * Return 0 on success or else a negative value.
+ */
+int ust_app_recv_notify(int sock)
+{
+ int ret;
+ enum ustctl_notify_cmd cmd;
+
+ DBG3("UST app receiving notify from sock %d", sock);
+
+ ret = ustctl_recv_notify(sock, &cmd);
+ if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app recv notify failed with ret %d", ret);
+ } else {
+ DBG3("UST app recv notify failed. Application died");
+ }
+ goto error;
+ }
+
+ switch (cmd) {
+ case USTCTL_NOTIFY_CMD_EVENT:
+ {
+ int sobjd, cobjd, loglevel;
+ char name[LTTNG_UST_SYM_NAME_LEN], *sig, *model_emf_uri;
+ size_t nr_fields;
+ struct ustctl_field *fields;
+
+ DBG2("UST app ustctl register event received");
+
+ ret = ustctl_recv_register_event(sock, &sobjd, &cobjd, name, &loglevel,
+ &sig, &nr_fields, &fields, &model_emf_uri);
+ if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app recv event failed with ret %d", ret);
+ } else {
+ DBG3("UST app recv event failed. Application died");
+ }
+ goto error;
+ }
+
+ /* Add event to the UST registry coming from the notify socket. */
+ ret = add_event_ust_registry(sock, sobjd, cobjd, name, sig, nr_fields,
+ fields, loglevel, model_emf_uri);
+ if (ret < 0) {
+ goto error;
+ }
+
+ break;
+ }
+ case USTCTL_NOTIFY_CMD_CHANNEL:
+ {
+ int sobjd, cobjd;
+ size_t nr_fields;
+ struct ustctl_field *fields;
+
+ DBG2("UST app ustctl register channel received");
+
+ ret = ustctl_recv_register_channel(sock, &sobjd, &cobjd, &nr_fields,
+ &fields);
+ if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("UST app recv channel failed with ret %d", ret);
+ } else {
+ DBG3("UST app recv channel failed. Application died");
+ }
+ goto error;
+ }
+
+ ret = reply_ust_register_channel(sock, sobjd, cobjd, nr_fields,
+ fields);
+ if (ret < 0) {
+ goto error;
+ }
+
+ break;
+ }
+ default:
+ /* Should NEVER happen. */
+ assert(0);
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Once the notify socket hangs up, this is called. First, it tries to find the
+ * corresponding application. On failure, the call_rcu to close the socket is
+ * executed. If an application is found, it tries to delete it from the notify
+ * socket hash table. Whathever the result, it proceeds to the call_rcu.
+ *
+ * Note that an object needs to be allocated here so on ENOMEM failure, the
+ * call RCU is not done but the rest of the cleanup is.
+ */
+void ust_app_notify_sock_unregister(int sock)
+{
+ int err_enomem = 0;
+ struct lttng_ht_iter iter;
+ struct ust_app *app;
+ struct ust_app_notify_sock_obj *obj;
+
+ assert(sock >= 0);
+
+ rcu_read_lock();
+
+ obj = zmalloc(sizeof(*obj));
+ if (!obj) {
+ /*
+ * An ENOMEM is kind of uncool. If this strikes we continue the
+ * procedure but the call_rcu will not be called. In this case, we
+ * accept the fd leak rather than possibly creating an unsynchronized
+ * state between threads.
+ *
+ * TODO: The notify object should be created once the notify socket is
+ * registered and stored independantely from the ust app object. The
+ * tricky part is to synchronize the teardown of the application and
+ * this notify object. Let's keep that in mind so we can avoid this
+ * kind of shenanigans with ENOMEM in the teardown path.
+ */
+ err_enomem = 1;
+ } else {
+ obj->fd = sock;
+ }
+
+ DBG("UST app notify socket unregister %d", sock);
+
+ /*
+ * Lookup application by notify socket. If this fails, this means that the
+ * hash table delete has already been done by the application
+ * unregistration process so we can safely close the notify socket in a
+ * call RCU.
+ */
+ app = find_app_by_notify_sock(sock);
+ if (!app) {
+ goto close_socket;
+ }
+
+ iter.iter.node = &app->notify_sock_n.node;
+
+ /*
+ * Whatever happens here either we fail or succeed, in both cases we have
+ * to close the socket after a grace period to continue to the call RCU
+ * here. If the deletion is successful, the application is not visible
+ * anymore by other threads and is it fails it means that it was already
+ * deleted from the hash table so either way we just have to close the
+ * socket.
+ */
+ (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
+
+close_socket:
+ rcu_read_unlock();
+
+ /*
+ * Close socket after a grace period to avoid for the socket to be reused
+ * before the application object is freed creating potential race between
+ * threads trying to add unique in the global hash table.
+ */
+ if (!err_enomem) {
+ call_rcu(&obj->head, close_notify_sock_rcu);
+ }
+}
projects / lttng-tools.git / blobdiff