free(stream);
}
+/*
+ * We need to execute ht_destroy outside of RCU read-side critical
+ * section, so we postpone its execution using call_rcu. It is simpler
+ * than to change the semantic of the many callers of
+ * delete_ust_app_channel().
+ */
+static
+void delete_ust_app_channel_rcu(struct rcu_head *head)
+{
+ struct ust_app_channel *ua_chan =
+ caa_container_of(head, struct ust_app_channel, rcu_head);
+
+ lttng_ht_destroy(ua_chan->ctx);
+ lttng_ht_destroy(ua_chan->events);
+ free(ua_chan);
+}
+
/*
* Delete ust app channel safely. RCU read lock must be held before calling
* this function.
assert(!ret);
delete_ust_app_ctx(sock, ua_ctx);
}
- lttng_ht_destroy(ua_chan->ctx);
/* Wipe events */
cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event,
assert(!ret);
delete_ust_app_event(sock, ua_event);
}
- lttng_ht_destroy(ua_chan->events);
/* Wipe and free registry from session registry. */
registry = get_session_registry(ua_chan->session);
lttng_fd_put(LTTNG_FD_APPS, 1);
free(ua_chan->obj);
}
- free(ua_chan);
+ call_rcu(&ua_chan->rcu_head, delete_ust_app_channel_rcu);
}
/*
return ret;
}
+/*
+ * We need to execute ht_destroy outside of RCU read-side critical
+ * section, so we postpone its execution using call_rcu. It is simpler
+ * than to change the semantic of the many callers of
+ * delete_ust_app_session().
+ */
+static
+void delete_ust_app_session_rcu(struct rcu_head *head)
+{
+ struct ust_app_session *ua_sess =
+ caa_container_of(head, struct ust_app_session, rcu_head);
+
+ lttng_ht_destroy(ua_sess->channels);
+ free(ua_sess);
+}
+
/*
* Delete ust app session safely. RCU read lock must be held before calling
* this function.
assert(!ret);
delete_ust_app_channel(sock, ua_chan, app);
}
- lttng_ht_destroy(ua_sess->channels);
/* In case of per PID, the registry is kept in the session. */
if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
sock, ret);
}
}
- free(ua_sess);
+ call_rcu(&ua_sess->rcu_head, delete_ust_app_session_rcu);
}
/*
* Delete a traceable application structure from the global list. Never call
* this function outside of a call_rcu call.
+ *
+ * RCU read side lock should _NOT_ be held when calling this function.
*/
static
void delete_ust_app(struct ust_app *app)
int ret, sock;
struct ust_app_session *ua_sess, *tmp_ua_sess;
- rcu_read_lock();
-
/* Delete ust app sessions info */
sock = app->sock;
app->sock = -1;
- lttng_ht_destroy(app->sessions);
-
/* Wipe sessions */
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. */
+ rcu_read_lock();
delete_ust_app_session(sock, ua_sess, app);
+ rcu_read_unlock();
}
+
+ lttng_ht_destroy(app->sessions);
lttng_ht_destroy(app->ust_objd);
/*
DBG2("UST app pid %d deleted", app->pid);
free(app);
-
- rcu_read_unlock();
}
/*
* 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.
+ * Called with UST app session lock and RCU read-side lock held.
*
* Return 0 on success or else a negative value.
*/
/*
* Free and clean all traceable apps of the global list.
+ *
+ * Should _NOT_ be called with RCU read-side lock held.
*/
void ust_app_clean_list(void)
{
ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
assert(!ret);
}
+ rcu_read_unlock();
/* 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();
}
/*
/*
* Start tracing for a specific UST session and app.
*/
+static
int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
{
int ret = 0;
/*
* Stop tracing for a specific UST session and app.
*/
+static
int ust_app_stop_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_registry_session *registry;
DBG("Stopping tracing for ust app pid %d", app->pid);
health_code_update();
+ registry = get_session_registry(ua_sess);
+ assert(registry);
+ /* Push metadata for application before freeing the application. */
+ (void) push_metadata(registry, ua_sess->consumer);
+
+ pthread_mutex_unlock(&ua_sess->lock);
+end_no_session:
+ rcu_read_unlock();
+ health_code_update();
+ return 0;
+
+error_rcu_unlock:
+ pthread_mutex_unlock(&ua_sess->lock);
+ rcu_read_unlock();
+ health_code_update();
+ return -1;
+}
+
+/*
+ * Flush buffers for a specific UST session and app.
+ */
+static
+int ust_app_flush_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;
+
+ DBG("Flushing buffers for ust app pid %d", app->pid);
+
+ rcu_read_lock();
+
+ if (!app->compatible) {
+ goto end_no_session;
+ }
+
+ ua_sess = lookup_session_by_app(usess, app);
+ if (ua_sess == NULL) {
+ goto end_no_session;
+ }
+
+ pthread_mutex_lock(&ua_sess->lock);
+
+ health_code_update();
+
/* Flushing buffers */
cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
node.node) {
health_code_update();
- registry = get_session_registry(ua_sess);
- assert(registry);
- /* Push metadata for application before freeing the application. */
- (void) push_metadata(registry, ua_sess->consumer);
-
pthread_mutex_unlock(&ua_sess->lock);
end_no_session:
rcu_read_unlock();
health_code_update();
return 0;
-
-error_rcu_unlock:
- pthread_mutex_unlock(&ua_sess->lock);
- rcu_read_unlock();
- health_code_update();
- return -1;
}
/*
rcu_read_lock();
- /* Flush all per UID buffers associated to that session. */
- if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
+ 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) {
+ /* Continue to next apps even on error */
+ continue;
+ }
+ }
+
+ /* Flush buffers */
+ switch (usess->buffer_type) {
+ case LTTNG_BUFFER_PER_UID:
+ {
struct buffer_reg_uid *reg;
+
+ /* Flush all per UID buffers associated to that session. */
cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
struct buffer_reg_channel *reg_chan;
struct consumer_socket *socket;
(void) consumer_flush_channel(socket, reg_chan->consumer_key);
}
}
+ break;
}
-
- 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) {
- /* Continue to next apps even on error */
- continue;
+ case LTTNG_BUFFER_PER_PID:
+ cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
+ ret = ust_app_flush_trace(usess, app);
+ if (ret < 0) {
+ /* Continue to next apps even on error */
+ continue;
+ }
}
+ break;
+ default:
+ assert(0);
+ break;
}
rcu_read_unlock();
projects / lttng-tools.git / blobdiff