struct cds_list_head list;
/* Node in the channel_triggers_ht */
struct cds_lfht_node channel_triggers_ht_node;
+ /* call_rcu delayed reclaim. */
+ struct rcu_head rcu_node;
};
/*
struct lttng_trigger_ht_element {
struct lttng_trigger *trigger;
struct cds_lfht_node node;
+ /* call_rcu delayed reclaim. */
+ struct rcu_head rcu_node;
};
struct lttng_condition_list_element {
};
struct notification_client_list {
- struct lttng_trigger *trigger;
+ const struct lttng_trigger *trigger;
struct cds_list_head list;
struct cds_lfht_node notification_trigger_ht_node;
+ /* call_rcu delayed reclaim. */
+ struct rcu_head rcu_node;
};
struct notification_client {
struct lttng_dynamic_buffer buffer;
} outbound;
} communication;
+ /* call_rcu delayed reclaim. */
+ struct rcu_head rcu_node;
};
struct channel_state_sample {
uint64_t highest_usage;
uint64_t lowest_usage;
uint64_t channel_total_consumed;
+ /* call_rcu delayed reclaim. */
+ struct rcu_head rcu_node;
};
static unsigned long hash_channel_key(struct channel_key *key);
{
struct lttng_condition *condition_key = (struct lttng_condition *) key;
struct notification_client_list *client_list;
- struct lttng_condition *condition;
+ const struct lttng_condition *condition;
assert(condition_key);
client_list = caa_container_of(node, struct notification_client_list,
notification_trigger_ht_node);
- condition = lttng_trigger_get_condition(client_list->trigger);
+ condition = lttng_trigger_get_const_condition(client_list->trigger);
return !!lttng_condition_is_equal(condition_key, condition);
}
+static
+int match_session(struct cds_lfht_node *node, const void *key)
+{
+ const char *name = key;
+ struct session_info *session_info = caa_container_of(
+ node, struct session_info, sessions_ht_node);
+
+ return !strcmp(session_info->name, name);
+}
+
static
unsigned long lttng_condition_buffer_usage_hash(
const struct lttng_condition *_condition)
return key_hash ^ domain_hash;
}
+/*
+ * Get the type of object to which a given condition applies. Bindings let
+ * the notification system evaluate a trigger's condition when a given
+ * object's state is updated.
+ *
+ * For instance, a condition bound to a channel will be evaluated everytime
+ * the channel's state is changed by a channel monitoring sample.
+ */
+static
+enum lttng_object_type get_condition_binding_object(
+ const struct lttng_condition *condition)
+{
+ switch (lttng_condition_get_type(condition)) {
+ case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW:
+ case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH:
+ case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE:
+ return LTTNG_OBJECT_TYPE_CHANNEL;
+ case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING:
+ case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED:
+ return LTTNG_OBJECT_TYPE_SESSION;
+ default:
+ return LTTNG_OBJECT_TYPE_UNKNOWN;
+ }
+}
+
+static
+void free_channel_info_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct channel_info, rcu_node));
+}
+
static
void channel_info_destroy(struct channel_info *channel_info)
{
if (channel_info->name) {
free(channel_info->name);
}
- free(channel_info);
+ call_rcu(&channel_info->rcu_node, free_channel_info_rcu);
+}
+
+static
+void free_session_info_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct session_info, rcu_node));
}
/* Don't call directly, use the ref-counting mechanism. */
&session_info->sessions_ht_node);
rcu_read_unlock();
free(session_info->name);
- free(session_info);
+ call_rcu(&session_info->rcu_node, free_session_info_rcu);
}
static
/* This function must be called with the RCU read lock held. */
static
-int evaluate_condition_for_client(struct lttng_trigger *trigger,
- struct lttng_condition *condition,
- struct notification_client *client,
- struct notification_thread_state *state)
+int evaluate_channel_condition_for_client(
+ const struct lttng_condition *condition,
+ struct notification_thread_state *state,
+ struct lttng_evaluation **evaluation,
+ uid_t *session_uid, gid_t *session_gid)
{
int ret;
struct cds_lfht_iter iter;
struct channel_key *channel_key = NULL;
struct channel_state_sample *last_sample = NULL;
struct lttng_channel_trigger_list *channel_trigger_list = NULL;
- struct lttng_evaluation *evaluation = NULL;
- struct notification_client_list client_list = { 0 };
- struct notification_client_list_element client_list_element = { 0 };
-
- assert(trigger);
- assert(condition);
- assert(client);
- assert(state);
- /* Find the channel associated with the trigger. */
+ /* Find the channel associated with the condition. */
cds_lfht_for_each_entry(state->channel_triggers_ht, &iter,
- channel_trigger_list , channel_triggers_ht_node) {
+ channel_trigger_list, channel_triggers_ht_node) {
struct lttng_trigger_list_element *element;
cds_list_for_each_entry(element, &channel_trigger_list->list, node) {
const struct lttng_condition *current_condition =
- lttng_trigger_get_const_condition(
+ lttng_trigger_get_const_condition(
element->trigger);
assert(current_condition);
if (!channel_key){
/* No channel found; normal exit. */
- DBG("[notification-thread] No channel associated with newly subscribed-to condition");
+ DBG("[notification-thread] No known channel associated with newly subscribed-to condition");
ret = 0;
goto end;
}
goto end;
}
- ret = evaluate_buffer_condition(condition, &evaluation, state,
+ ret = evaluate_buffer_condition(condition, evaluation, state,
NULL, last_sample,
0, channel_info->session_info->consumed_data_size,
channel_info);
goto end;
}
+ *session_uid = channel_info->session_info->uid;
+ *session_gid = channel_info->session_info->gid;
+end:
+ return ret;
+}
+
+static
+const char *get_condition_session_name(const struct lttng_condition *condition)
+{
+ const char *session_name = NULL;
+ enum lttng_condition_status status;
+
+ switch (lttng_condition_get_type(condition)) {
+ case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW:
+ case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH:
+ status = lttng_condition_buffer_usage_get_session_name(
+ condition, &session_name);
+ break;
+ case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE:
+ status = lttng_condition_session_consumed_size_get_session_name(
+ condition, &session_name);
+ break;
+ case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING:
+ case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED:
+ status = lttng_condition_session_rotation_get_session_name(
+ condition, &session_name);
+ break;
+ default:
+ abort();
+ }
+ if (status != LTTNG_CONDITION_STATUS_OK) {
+ ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
+ goto end;
+ }
+end:
+ return session_name;
+}
+
+/* This function must be called with the RCU read lock held. */
+static
+int evaluate_session_condition_for_client(
+ const struct lttng_condition *condition,
+ struct notification_thread_state *state,
+ struct lttng_evaluation **evaluation,
+ uid_t *session_uid, gid_t *session_gid)
+{
+ int ret;
+ struct cds_lfht_iter iter;
+ struct cds_lfht_node *node;
+ const char *session_name;
+ struct session_info *session_info = NULL;
+
+ session_name = get_condition_session_name(condition);
+
+ /* Find the session associated with the trigger. */
+ cds_lfht_lookup(state->sessions_ht,
+ hash_key_str(session_name, lttng_ht_seed),
+ match_session,
+ session_name,
+ &iter);
+ node = cds_lfht_iter_get_node(&iter);
+ if (!node) {
+ DBG("[notification-thread] No known session matching name \"%s\"",
+ session_name);
+ ret = 0;
+ goto end;
+ }
+
+ session_info = caa_container_of(node, struct session_info,
+ sessions_ht_node);
+ session_info_get(session_info);
+
+ /*
+ * Evaluation is performed in-line here since only one type of
+ * session-bound condition is handled for the moment.
+ */
+ switch (lttng_condition_get_type(condition)) {
+ case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING:
+ if (!session_info->rotation.ongoing) {
+ ret = 0;
+ goto end_session_put;
+ }
+
+ *evaluation = lttng_evaluation_session_rotation_ongoing_create(
+ session_info->rotation.id);
+ if (!*evaluation) {
+ /* Fatal error. */
+ ERR("[notification-thread] Failed to create session rotation ongoing evaluation for session \"%s\"",
+ session_info->name);
+ ret = -1;
+ goto end_session_put;
+ }
+ ret = 0;
+ break;
+ default:
+ ret = 0;
+ goto end_session_put;
+ }
+
+ *session_uid = session_info->uid;
+ *session_gid = session_info->gid;
+
+end_session_put:
+ session_info_put(session_info);
+end:
+ return ret;
+}
+
+/* This function must be called with the RCU read lock held. */
+static
+int evaluate_condition_for_client(const struct lttng_trigger *trigger,
+ const struct lttng_condition *condition,
+ struct notification_client *client,
+ struct notification_thread_state *state)
+{
+ int ret;
+ struct lttng_evaluation *evaluation = NULL;
+ struct notification_client_list client_list = { 0 };
+ struct notification_client_list_element client_list_element = { 0 };
+ uid_t object_uid = 0;
+ gid_t object_gid = 0;
+
+ assert(trigger);
+ assert(condition);
+ assert(client);
+ assert(state);
+
+ switch (get_condition_binding_object(condition)) {
+ case LTTNG_OBJECT_TYPE_SESSION:
+ ret = evaluate_session_condition_for_client(condition, state,
+ &evaluation, &object_uid, &object_gid);
+ break;
+ case LTTNG_OBJECT_TYPE_CHANNEL:
+ ret = evaluate_channel_condition_for_client(condition, state,
+ &evaluation, &object_uid, &object_gid);
+ break;
+ case LTTNG_OBJECT_TYPE_NONE:
+ ret = 0;
+ goto end;
+ case LTTNG_OBJECT_TYPE_UNKNOWN:
+ default:
+ ret = -1;
+ goto end;
+ }
+
if (!evaluation) {
/* Evaluation yielded nothing. Normal exit. */
DBG("[notification-thread] Newly subscribed-to condition evaluated to false, nothing to report to client");
/* Send evaluation result to the newly-subscribed client. */
DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client");
ret = send_evaluation_to_clients(trigger, evaluation, &client_list,
- state, channel_info->session_info->uid,
- channel_info->session_info->gid);
+ state, object_uid, object_gid);
end:
return ret;
return 0;
}
+static
+void free_notification_client_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct notification_client, rcu_node));
+}
+
static
void notification_client_destroy(struct notification_client *client,
struct notification_thread_state *state)
}
lttng_dynamic_buffer_reset(&client->communication.inbound.buffer);
lttng_dynamic_buffer_reset(&client->communication.outbound.buffer);
- free(client);
+ call_rcu(&client->rcu_node, free_notification_client_rcu);
}
/*
return false;
}
-/*
- * Get the type of object to which a given trigger applies. Binding lets
- * the notification system evaluate a trigger's condition when a given
- * object's state is updated.
- *
- * For instance, a condition bound to a channel will be evaluated everytime
- * the channel's state is changed by a channel monitoring sample.
- */
-static
-enum lttng_object_type get_trigger_binding_object(
- const struct lttng_trigger *trigger)
-{
- const struct lttng_condition *condition;
-
- condition = lttng_trigger_get_const_condition(trigger);
- switch (lttng_condition_get_type(condition)) {
- case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW:
- case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH:
- case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE:
- return LTTNG_OBJECT_TYPE_CHANNEL;
- case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING:
- case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED:
- return LTTNG_OBJECT_TYPE_SESSION;
- default:
- return LTTNG_OBJECT_TYPE_UNKNOWN;
- }
-}
-
static
bool trigger_applies_to_channel(const struct lttng_trigger *trigger,
const struct channel_info *channel_info)
return applies;
}
-static
-int match_session(struct cds_lfht_node *node, const void *key)
-{
- const char *name = key;
- struct session_info *session_info = caa_container_of(
- node, struct session_info, sessions_ht_node);
-
- return !strcmp(session_info->name, name);
-}
-
/* Must be called with RCU read lock held. */
static
struct lttng_session_trigger_list *get_session_trigger_list(
if (!session) {
ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
name, uid, gid);
+ lttng_session_trigger_list_destroy(trigger_list);
goto error;
}
trigger_list = NULL;
session_info = find_or_create_session_info(state, session_name,
session_uid, session_gid);
if (!session_info) {
- /* Allocation error or an internal error occured. */
+ /* Allocation error or an internal error occurred. */
goto error;
}
goto error;
}
+ rcu_read_lock();
/* Build a list of all triggers applying to the new channel. */
cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element,
node) {
new_element = zmalloc(sizeof(*new_element));
if (!new_element) {
+ rcu_read_unlock();
goto error;
}
CDS_INIT_LIST_HEAD(&new_element->node);
cds_list_add(&new_element->node, &trigger_list);
trigger_count++;
}
+ rcu_read_unlock();
DBG("[notification-thread] Found %i triggers that apply to newly added channel",
trigger_count);
return 1;
}
+static
+void free_channel_trigger_list_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct lttng_channel_trigger_list,
+ rcu_node));
+}
+
+static
+void free_channel_state_sample_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct channel_state_sample,
+ rcu_node));
+}
+
static
int handle_notification_thread_command_remove_channel(
struct notification_thread_state *state,
free(trigger_list_element);
}
cds_lfht_del(state->channel_triggers_ht, node);
- free(trigger_list);
+ call_rcu(&trigger_list->rcu_node, free_channel_trigger_list_rcu);
/* Free sampled channel state. */
cds_lfht_lookup(state->channel_state_ht,
channel_state_ht_node);
cds_lfht_del(state->channel_state_ht, node);
- free(sample);
+ call_rcu(&sample->rcu_node, free_channel_state_sample_rcu);
}
/* Remove the channel from the channels_ht and free it. */
session_info = find_or_create_session_info(state, session_name,
session_uid, session_gid);
if (!session_info) {
- /* Allocation error or an internal error occured. */
+ /* Allocation error or an internal error occurred. */
ret = -1;
cmd_result = LTTNG_ERR_NOMEM;
goto end;
channels_ht_node) {
struct lttng_trigger_list_element *trigger_list_element;
struct lttng_channel_trigger_list *trigger_list;
+ struct cds_lfht_iter lookup_iter;
if (!trigger_applies_to_channel(trigger, channel)) {
continue;
hash_channel_key(&channel->key),
match_channel_trigger_list,
&channel->key,
- &iter);
- node = cds_lfht_iter_get_node(&iter);
+ &lookup_iter);
+ node = cds_lfht_iter_get_node(&lookup_iter);
assert(node);
trigger_list = caa_container_of(node,
struct lttng_channel_trigger_list,
lttng_condition_hash(condition),
&client_list->notification_trigger_ht_node);
- switch (get_trigger_binding_object(trigger)) {
+ switch (get_condition_binding_object(condition)) {
case LTTNG_OBJECT_TYPE_SESSION:
/* Add the trigger to the list if it matches a known session. */
ret = bind_trigger_to_matching_session(trigger, state);
if (ret) {
goto error_free_client_list;
}
+ break;
case LTTNG_OBJECT_TYPE_CHANNEL:
/*
* Add the trigger to list of triggers bound to the channels
return ret;
}
+static
+void free_notification_client_list_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct notification_client_list,
+ rcu_node));
+}
+
+static
+void free_lttng_trigger_ht_element_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct lttng_trigger_ht_element,
+ rcu_node));
+}
+
static
int handle_notification_thread_command_unregister_trigger(
struct notification_thread_state *state,
}
cds_lfht_del(state->notification_trigger_clients_ht,
&client_list->notification_trigger_ht_node);
- free(client_list);
+ call_rcu(&client_list->rcu_node, free_notification_client_list_rcu);
/* Remove trigger from triggers_ht. */
trigger_ht_element = caa_container_of(triggers_ht_node,
action = lttng_trigger_get_action(trigger_ht_element->trigger);
lttng_action_destroy(action);
lttng_trigger_destroy(trigger_ht_element->trigger);
- free(trigger_ht_element);
+ call_rcu(&trigger_ht_element->rcu_node, free_lttng_trigger_ht_element_rcu);
end:
rcu_read_unlock();
if (_cmd_reply) {
struct notification_thread_command *cmd;
/* Read the event pipe to put it back into a quiescent state. */
- ret = read(lttng_pipe_get_readfd(handle->cmd_queue.event_pipe), &counter,
+ ret = lttng_read(lttng_pipe_get_readfd(handle->cmd_queue.event_pipe), &counter,
sizeof(counter));
- if (ret == -1) {
+ if (ret != sizeof(counter)) {
goto error;
}
struct cds_lfht_iter iter;
struct lttng_trigger_ht_element *trigger_ht_element;
+ rcu_read_lock();
cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element,
node) {
int ret = handle_notification_thread_command_unregister_trigger(
error_occurred = true;
}
}
+ rcu_read_unlock();
return error_occurred ? -1 : 0;
}
projects / lttng-tools.git / blobdiff