#include <lttng/condition/condition-internal.h>
#include <lttng/condition/buffer-usage-internal.h>
#include <lttng/condition/session-consumed-size-internal.h>
+#include <lttng/condition/session-rotation-internal.h>
#include <lttng/notification/channel-internal.h>
#include <time.h>
struct lttng_channel_trigger_list {
struct channel_key channel_key;
+ /* List of struct lttng_trigger_list_element. */
struct cds_list_head list;
+ /* Node in the channel_triggers_ht */
struct cds_lfht_node channel_triggers_ht_node;
};
+/*
+ * List of triggers applying to a given session.
+ *
+ * See:
+ * - lttng_session_trigger_list_create()
+ * - lttng_session_trigger_list_build()
+ * - lttng_session_trigger_list_destroy()
+ * - lttng_session_trigger_list_add()
+ */
+struct lttng_session_trigger_list {
+ /*
+ * Not owned by this; points to the session_info structure's
+ * session name.
+ */
+ const char *session_name;
+ /* List of struct lttng_trigger_list_element. */
+ struct cds_list_head list;
+ /* Node in the session_triggers_ht */
+ struct cds_lfht_node session_triggers_ht_node;
+ /*
+ * Weak reference to the notification system's session triggers
+ * hashtable.
+ *
+ * The session trigger list structure structure is owned by
+ * the session's session_info.
+ *
+ * The session_info is kept alive the the channel_infos holding a
+ * reference to it (reference counting). When those channels are
+ * destroyed (at runtime or on teardown), the reference they hold
+ * to the session_info are released. On destruction of session_info,
+ * session_info_destroy() will remove the list of triggers applying
+ * to this session from the notification system's state.
+ *
+ * This implies that the session_triggers_ht must be destroyed
+ * after the channels.
+ */
+ struct cds_lfht *session_triggers_ht;
+ /* Used for delayed RCU reclaim. */
+ struct rcu_head rcu_node;
+};
+
struct lttng_trigger_ht_element {
struct lttng_trigger *trigger;
struct cds_lfht_node node;
uid_t channel_uid, gid_t channel_gid);
+/* session_info API */
static
void session_info_destroy(void *_data);
static
void session_info_put(struct session_info *session_info);
static
struct session_info *session_info_create(const char *name,
- uid_t uid, gid_t gid);
+ uid_t uid, gid_t gid,
+ struct lttng_session_trigger_list *trigger_list);
static
void session_info_add_channel(struct session_info *session_info,
struct channel_info *channel_info);
void session_info_remove_channel(struct session_info *session_info,
struct channel_info *channel_info);
+/* lttng_session_trigger_list API */
+static
+struct lttng_session_trigger_list *lttng_session_trigger_list_create(
+ const char *session_name,
+ struct cds_lfht *session_triggers_ht);
+static
+struct lttng_session_trigger_list *lttng_session_trigger_list_build(
+ const struct notification_thread_state *state,
+ const char *session_name);
+static
+void lttng_session_trigger_list_destroy(
+ struct lttng_session_trigger_list *list);
+static
+int lttng_session_trigger_list_add(struct lttng_session_trigger_list *list,
+ const struct lttng_trigger *trigger);
+
+
static
int match_client(struct cds_lfht_node *node, const void *key)
{
ERR("[notification-thread] Failed to destroy channel information hash table");
}
}
+ lttng_session_trigger_list_destroy(session_info->trigger_list);
free(session_info->name);
free(session_info);
}
}
static
-struct session_info *session_info_create(const char *name, uid_t uid, gid_t gid)
+struct session_info *session_info_create(const char *name, uid_t uid, gid_t gid,
+ struct lttng_session_trigger_list *trigger_list)
{
struct session_info *session_info;
}
session_info->uid = uid;
session_info->gid = gid;
+ session_info->trigger_list = trigger_list;
end:
return session_info;
error:
return !strcmp(session_info->name, name);
}
+/*
+ * Allocate an empty lttng_session_trigger_list for the session named
+ * 'session_name'.
+ *
+ * No ownership of 'session_name' is assumed by the session trigger list.
+ * It is the caller's responsability to ensure the session name is alive
+ * for as long as this list is.
+ */
+static
+struct lttng_session_trigger_list *lttng_session_trigger_list_create(
+ const char *session_name,
+ struct cds_lfht *session_triggers_ht)
+{
+ struct lttng_session_trigger_list *list;
+
+ list = zmalloc(sizeof(*list));
+ if (!list) {
+ goto end;
+ }
+ list->session_name = session_name;
+ CDS_INIT_LIST_HEAD(&list->list);
+ cds_lfht_node_init(&list->session_triggers_ht_node);
+ list->session_triggers_ht = session_triggers_ht;
+
+ rcu_read_lock();
+ /* Publish the list through the session_triggers_ht. */
+ cds_lfht_add(session_triggers_ht,
+ hash_key_str(session_name, lttng_ht_seed),
+ &list->session_triggers_ht_node);
+ rcu_read_unlock();
+end:
+ return list;
+}
+
+static
+void free_session_trigger_list_rcu(struct rcu_head *node)
+{
+ free(caa_container_of(node, struct lttng_session_trigger_list,
+ rcu_node));
+}
+
+static
+void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list *list)
+{
+ struct lttng_trigger_list_element *trigger_list_element, *tmp;
+
+ /* Empty the list element by element, and then free the list itself. */
+ cds_list_for_each_entry_safe(trigger_list_element, tmp,
+ &list->list, node) {
+ cds_list_del(&trigger_list_element->node);
+ free(trigger_list_element);
+ }
+ rcu_read_lock();
+ /* Unpublish the list from the session_triggers_ht. */
+ cds_lfht_del(list->session_triggers_ht,
+ &list->session_triggers_ht_node);
+ rcu_read_unlock();
+ call_rcu(&list->rcu_node, free_session_trigger_list_rcu);
+}
+
+static
+int lttng_session_trigger_list_add(struct lttng_session_trigger_list *list,
+ const struct lttng_trigger *trigger)
+{
+ int ret = 0;
+ struct lttng_trigger_list_element *new_element =
+ zmalloc(sizeof(*new_element));
+
+ if (!new_element) {
+ ret = -1;
+ goto end;
+ }
+ CDS_INIT_LIST_HEAD(&new_element->node);
+ new_element->trigger = trigger;
+ cds_list_add(&new_element->node, &list->list);
+end:
+ return ret;
+}
+
+static
+bool trigger_applies_to_session(const struct lttng_trigger *trigger,
+ const char *session_name)
+{
+ bool applies = false;
+ const struct lttng_condition *condition;
+
+ condition = lttng_trigger_get_const_condition(trigger);
+ switch (lttng_condition_get_type(condition)) {
+ case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING:
+ case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED:
+ {
+ enum lttng_condition_status condition_status;
+ const char *condition_session_name;
+
+ condition_status = lttng_condition_session_rotation_get_session_name(
+ condition, &condition_session_name);
+ if (condition_status != LTTNG_CONDITION_STATUS_OK) {
+ ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
+ goto end;
+ }
+
+ assert(condition_session_name);
+ applies = !strcmp(condition_session_name, session_name);
+ break;
+ }
+ default:
+ goto end;
+ }
+end:
+ return applies;
+}
+
+/*
+ * Allocate and initialize an lttng_session_trigger_list which contains
+ * all triggers that apply to the session named 'session_name'.
+ *
+ * No ownership of 'session_name' is assumed by the session trigger list.
+ * It is the caller's responsability to ensure the session name is alive
+ * for as long as this list is.
+ */
+static
+struct lttng_session_trigger_list *lttng_session_trigger_list_build(
+ const struct notification_thread_state *state,
+ const char *session_name)
+{
+ int trigger_count = 0;
+ struct lttng_session_trigger_list *session_trigger_list = NULL;
+ struct lttng_trigger_ht_element *trigger_ht_element = NULL;
+ struct cds_lfht_iter iter;
+
+ session_trigger_list = lttng_session_trigger_list_create(session_name,
+ state->session_triggers_ht);
+
+ /* Add all triggers applying to the session named 'session_name'. */
+ cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element,
+ node) {
+ int ret;
+
+ if (!trigger_applies_to_session(trigger_ht_element->trigger,
+ session_name)) {
+ continue;
+ }
+
+ ret = lttng_session_trigger_list_add(session_trigger_list,
+ trigger_ht_element->trigger);
+ if (ret) {
+ goto error;
+ }
+
+ trigger_count++;
+ }
+
+ DBG("[notification-thread] Found %i triggers that apply to newly created session",
+ trigger_count);
+ return session_trigger_list;
+error:
+ lttng_session_trigger_list_destroy(session_trigger_list);
+ return NULL;
+}
+
static
struct session_info *find_or_create_session_info(
struct notification_thread_state *state,
struct session_info *session = NULL;
struct cds_lfht_node *node;
struct cds_lfht_iter iter;
+ struct lttng_session_trigger_list *trigger_list;
rcu_read_lock();
cds_lfht_lookup(state->sessions_ht,
sessions_ht_node);
assert(session->uid == uid);
assert(session->gid == gid);
- goto end;
+ goto error;
}
- session = session_info_create(name, uid, gid);
+ trigger_list = lttng_session_trigger_list_build(state, name);
+ if (!trigger_list) {
+ goto error;
+ }
+
+ session = session_info_create(name, uid, gid, trigger_list);
if (!session) {
ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
name, uid, gid);
- goto end;
+ goto error;
}
+ trigger_list = NULL;
cds_lfht_add(state->sessions_ht, hash_key_str(name, lttng_ht_seed),
&session->sessions_ht_node);
-end:
rcu_read_unlock();
return session;
+error:
+ rcu_read_unlock();
+ session_info_put(session);
+ return NULL;
}
static
* - channel_triggers_ht:
* associates a channel key to a list of
* struct lttng_trigger_list_nodes. The triggers in this list are
- * those that have conditions that apply to this channel.
+ * those that have conditions that apply to a particular channel.
* A channel entry is only created when a channel is added; the
* list of triggers applying to such a channel is built at that
* moment.
* This hash table owns the list, but not the triggers themselves.
*
+ * - session_triggers_ht:
+ * associates a session name to a list of
+ * struct lttng_trigger_list_nodes. The triggers in this list are
+ * those that have conditions that apply to a particular session.
+ * A session entry is only created when a session is created; the
+ * list of triggers applying to this new session is built at that
+ * moment. This happens at the time of creation of a session_info.
+ * Likewise, the list is destroyed at the time of the session_info's
+ * destruction.
+ *
* - channel_state_ht:
* associates a pair (channel key, channel domain) to its last
* sampled state received from the consumer daemon
* triggers which apply to this new channel,
* - triggers identified are added to the channel_triggers_ht.
* - add channel to channels_ht
+ * - if it is the first channel of a session, a session_info is created and
+ * added to the sessions_ht. A list of the triggers associated with that
+ * session is built, and it is added to session_triggers_ht.
*
* 2) Destruction of a tracing channel
* - remove entry from channel_triggers_ht, releasing the list wrapper and
* elements,
* - remove entry from the channel_state_ht.
* - remove channel from channels_ht
+ * - if it was the last known channel of a session, the session_info
+ * structure is torndown, which in return destroys the list of triggers
+ * applying to that session.
*
* 3) Registration of a trigger
* - if the trigger's action is of type "notify",
* - add list of clients (even if it is empty) to the
* notification_trigger_clients_ht,
* - add trigger to channel_triggers_ht (if applicable),
+ * - add trigger to session_triggers_ht (if applicable),
* - add trigger to triggers_ht
* - evaluate the trigger's condition right away to react if that condition
* is true from the beginning.
* - if the trigger's action is of type "notify",
* - remove the trigger from the notification_trigger_clients_ht,
* - remove trigger from channel_triggers_ht (if applicable),
+ * - remove trigger from session_triggers_ht (if applicable),
* - remove trigger from triggers_ht
*
* 5) Reception of a channel monitor sample from the consumer daemon
struct lttng_poll_event events;
struct cds_lfht *client_socket_ht;
struct cds_lfht *channel_triggers_ht;
+ struct cds_lfht *session_triggers_ht;
struct cds_lfht *channel_state_ht;
struct cds_lfht *notification_trigger_clients_ht;
struct cds_lfht *channels_ht;
projects / lttng-tools.git / commitdiff
