Fix: notification thread: RCU-safe reclaim of hash table nodes

[lttng-tools.git] / src / bin / lttng-sessiond / notification-thread-internal.h

diff --git a/src/bin/lttng-sessiond/notification-thread-internal.h b/src/bin/lttng-sessiond/notification-thread-internal.h
index 8149e2c2116a1ab0dd4cfc4581809c468872cdfa..e217995f56635c13efffb70f3f5b8eea9f7ecd18 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread-internal.h
+++ b/src/bin/lttng-sessiond/notification-thread-internal.h
@@ -33,13 +33,28 @@ struct session_info {
        uid_t uid;
        gid_t gid;
        /*
        uid_t uid;
        gid_t gid;
        /*

-        * Back-ref (weak) to all channels in this session.
+        * Hashtable containing back-refs (weak) to all channels in this session.

         * The hashtable's key is a hash of (struct channel_key) and
         * the value is of type (struct channel_info *).
         */
        struct cds_lfht *channel_infos_ht;
         * The hashtable's key is a hash of (struct channel_key) and
         * the value is of type (struct channel_info *).
         */
        struct cds_lfht *channel_infos_ht;

+       struct lttng_session_trigger_list *trigger_list;

        /* Node in the notification thread state's sessions_ht. */
        struct cds_lfht_node sessions_ht_node;
        /* Node in the notification thread state's sessions_ht. */
        struct cds_lfht_node sessions_ht_node;

+       /*
+        * Weak reference to the thread state's sessions_ht. Used for removal on
+        * destruction.
+        */
+       struct cds_lfht *sessions_ht;
+       uint64_t consumed_data_size;
+       struct {
+               /* Whether a rotation is ongoing for this session. */
+               bool ongoing;
+               /* Identifier of the currently ongoing rotation. */
+               uint64_t id;
+       } rotation;
+       /* call_rcu delayed reclaim. */
+       struct rcu_head rcu_node;

 };
 
 struct channel_info {
 };
 
 struct channel_info {


@@ -55,6 +70,8 @@ struct channel_info {
        struct cds_lfht_node channels_ht_node;
        /* Node in the session_info's channels_ht. */
        struct cds_lfht_node session_info_channels_ht_node;
        struct cds_lfht_node channels_ht_node;
        /* Node in the session_info's channels_ht. */
        struct cds_lfht_node session_info_channels_ht_node;

+       /* call_rcu delayed reclaim. */
+       struct rcu_head rcu_node;

 };
 
 #endif /* NOTIFICATION_THREAD_INTERNAL_H */
 };
 
 #endif /* NOTIFICATION_THREAD_INTERNAL_H */