Fix: remove session_info from sessions_ht on destruction

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c
index 4904a54575e512c1ed4297a98eed17e7abc95dea..c80d977da8a11fb553c1a4296f16ab9df1587dee 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread-events.c
+++ b/src/bin/lttng-sessiond/notification-thread-events.c
@@ -235,7 +235,8 @@ 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,
-               struct lttng_session_trigger_list *trigger_list);
+               struct lttng_session_trigger_list *trigger_list,
+               struct cds_lfht *sessions_ht);
 static
 void session_info_add_channel(struct session_info *session_info,
                struct channel_info *channel_info);
@@ -515,6 +516,11 @@ void session_info_destroy(void *_data)
                }
        }
        lttng_session_trigger_list_destroy(session_info->trigger_list);
+
+       rcu_read_lock();
+       cds_lfht_del(session_info->sessions_ht,
+                       &session_info->sessions_ht_node);
+       rcu_read_unlock();
        free(session_info->name);
        free(session_info);
 }
@@ -539,7 +545,8 @@ 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,
-               struct lttng_session_trigger_list *trigger_list)
+               struct lttng_session_trigger_list *trigger_list,
+               struct cds_lfht *sessions_ht)
 {
        struct session_info *session_info;
 
@@ -565,6 +572,7 @@ struct session_info *session_info_create(const char *name, uid_t uid, gid_t gid,
        session_info->uid = uid;
        session_info->gid = gid;
        session_info->trigger_list = trigger_list;
+       session_info->sessions_ht = sessions_ht;
 end:
        return session_info;
 error:
@@ -1316,7 +1324,8 @@ struct session_info *find_or_create_session_info(
                                sessions_ht_node);
                assert(session->uid == uid);
                assert(session->gid == gid);
-               goto error;
+               session_info_get(session);
+               goto end;
        }
 
        trigger_list = lttng_session_trigger_list_build(state, name);
@@ -1324,7 +1333,8 @@ struct session_info *find_or_create_session_info(
                goto error;
        }
 
-       session = session_info_create(name, uid, gid, trigger_list);
+       session = session_info_create(name, uid, gid, trigger_list,
+                       state->sessions_ht);
        if (!session) {
                ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
                                name, uid, gid);
@@ -1334,6 +1344,7 @@ struct session_info *find_or_create_session_info(
 
        cds_lfht_add(state->sessions_ht, hash_key_str(name, lttng_ht_seed),
                        &session->sessions_ht_node);
+end:
        rcu_read_unlock();
        return session;
 error:
@@ -1425,6 +1436,7 @@ int handle_notification_thread_command_add_channel(
                        hash_channel_key(&new_channel_info->key),
                        &channel_trigger_list->channel_triggers_ht_node);
        rcu_read_unlock();
+       session_info_put(session_info);
        *cmd_result = LTTNG_OK;
        return 0;
 error:

diff --git a/src/bin/lttng-sessiond/notification-thread-internal.h b/src/bin/lttng-sessiond/notification-thread-internal.h
index 0bd575c233be3250cf27f94bce467372134c4b1f..397159da7ef6c863ea63515b0b17e35b4c6f566e 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread-internal.h
+++ b/src/bin/lttng-sessiond/notification-thread-internal.h
@@ -41,6 +41,11 @@ struct session_info {
        struct lttng_session_trigger_list *trigger_list;
        /* 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. */