Fix: sessiond: don't allocate buffers and files for inactive sessions

[lttng-tools.git] / src / bin / lttng-sessiond / ust-app.c

diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index 7b44fb4b48a050927fe2c897650dd2fda156dfac..0b0a62532125e6bc7ecd4a72728f1b8e997a18ba 100644 (file)
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -437,6 +437,9 @@ void save_per_pid_lost_discarded_counters(struct ust_app_channel *ua_chan)
 
 end:
        rcu_read_unlock();
+       if (session) {
+               session_put(session);
+       }
 }
 
 /*
@@ -2865,7 +2868,7 @@ static int create_channel_per_uid(struct ust_app *app,
        int ret;
        struct buffer_reg_uid *reg_uid;
        struct buffer_reg_channel *reg_chan;
-       struct ltt_session *session;
+       struct ltt_session *session = NULL;
        enum lttng_error_code notification_ret;
        struct ust_registry_channel *chan_reg;
 
@@ -2968,6 +2971,9 @@ send_channel:
        }
 
 error:
+       if (session) {
+               session_put(session);
+       }
        return ret;
 }
 
@@ -2986,7 +2992,7 @@ static int create_channel_per_pid(struct ust_app *app,
        int ret;
        struct ust_registry_session *registry;
        enum lttng_error_code cmd_ret;
-       struct ltt_session *session;
+       struct ltt_session *session = NULL;
        uint64_t chan_reg_key;
        struct ust_registry_channel *chan_reg;
 
@@ -3061,6 +3067,9 @@ error_remove_from_registry:
        }
 error:
        rcu_read_unlock();
+       if (session) {
+               session_put(session);
+       }
        return ret;
 }
 
@@ -3251,7 +3260,7 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess,
        struct ust_app_channel *metadata;
        struct consumer_socket *socket;
        struct ust_registry_session *registry;
-       struct ltt_session *session;
+       struct ltt_session *session = NULL;
 
        assert(ua_sess);
        assert(app);
@@ -3342,6 +3351,9 @@ error_consumer:
        delete_ust_app_channel(-1, metadata, app);
 error:
        pthread_mutex_unlock(&registry->lock);
+       if (session) {
+               session_put(session);
+       }
        return ret;
 }
 
@@ -3909,6 +3921,24 @@ void ust_app_clean_list(void)
 
        rcu_read_lock();
 
+       /* Cleanup notify socket hash table */
+       if (ust_app_ht_by_notify_sock) {
+               cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app,
+                               notify_sock_n.node) {
+                       struct cds_lfht_node *node;
+                       struct ust_app *app;
+
+                       node = cds_lfht_iter_get_node(&iter.iter);
+                       if (!node) {
+                               continue;
+                       }
+
+                       app = container_of(node, struct ust_app,
+                                       notify_sock_n.node);
+                       ust_app_notify_sock_unregister(app->notify_sock);
+               }
+       }
+
        if (ust_app_ht) {
                cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
                        ret = lttng_ht_del(ust_app_ht, &iter);
@@ -3926,14 +3956,6 @@ void ust_app_clean_list(void)
                }
        }
 
-       /* Cleanup notify socket hash table */
-       if (ust_app_ht_by_notify_sock) {
-               cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app,
-                               notify_sock_n.node) {
-                       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 */
@@ -3990,6 +4012,10 @@ int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
        DBG2("UST app disabling channel %s from global domain for session id %" PRIu64,
                        uchan->name, usess->id);
 
+       if (!usess->active) {
+               goto end;
+       }
+
        rcu_read_lock();
 
        /* For every registered applications */
@@ -4028,6 +4054,7 @@ int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
        rcu_read_unlock();
 
 error:
+end:
        return ret;
 }
 
@@ -4051,6 +4078,10 @@ int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
        DBG2("UST app enabling channel %s to global domain for session id %" PRIu64,
                        uchan->name, usess->id);
 
+       if (!usess->active) {
+               goto end;
+       }
+
        rcu_read_lock();
 
        /* For every registered applications */
@@ -4078,6 +4109,7 @@ int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
        rcu_read_unlock();
 
 error:
+end:
        return ret;
 }
 
@@ -4099,6 +4131,10 @@ int ust_app_disable_event_glb(struct ltt_ust_session *usess,
                        "%s for session id %" PRIu64,
                        uevent->attr.name, uchan->name, usess->id);
 
+       if (!usess->active) {
+               goto end;
+       }
+
        rcu_read_lock();
 
        /* For all registered applications */
@@ -4143,7 +4179,7 @@ int ust_app_disable_event_glb(struct ltt_ust_session *usess,
        }
 
        rcu_read_unlock();
-
+end:
        return ret;
 }
 
@@ -4165,6 +4201,10 @@ int ust_app_create_channel_glb(struct ltt_ust_session *usess,
        DBG2("UST app adding channel %s to UST domain for session id %" PRIu64,
                        uchan->name, usess->id);
 
+       if (!usess->active) {
+               goto end;
+       }
+
        rcu_read_lock();
 
        /* For every registered applications */
@@ -4244,6 +4284,7 @@ int ust_app_create_channel_glb(struct ltt_ust_session *usess,
 
 error_rcu_unlock:
        rcu_read_unlock();
+end:
        return ret;
 }
 
@@ -4264,6 +4305,10 @@ int ust_app_enable_event_glb(struct ltt_ust_session *usess,
        DBG("UST app enabling event %s for all apps for session id %" PRIu64,
                        uevent->attr.name, usess->id);
 
+       if (!usess->active) {
+               goto end;
+       }
+
        /*
         * NOTE: At this point, this function is called only if the session and
         * channel passed are already created for all apps. and enabled on the
@@ -4329,6 +4374,7 @@ int ust_app_enable_event_glb(struct ltt_ust_session *usess,
 
 error:
        rcu_read_unlock();
+end:
        return ret;
 }
 
@@ -4349,6 +4395,10 @@ int ust_app_create_event_glb(struct ltt_ust_session *usess,
        DBG("UST app creating event %s for all apps for session id %" PRIu64,
                        uevent->attr.name, usess->id);
 
+       if (!usess->active) {
+               goto end;
+       }
+
        rcu_read_lock();
 
        /* For all registered applications */
@@ -4395,7 +4445,7 @@ int ust_app_create_event_glb(struct ltt_ust_session *usess,
        }
 
        rcu_read_unlock();
-
+end:
        return ret;
 }
 
@@ -4974,6 +5024,12 @@ int ust_app_start_trace_all(struct ltt_ust_session *usess)
 
        DBG("Starting all UST traces");
 
+       /*
+        * Even though the start trace might fail, flag this session active so
+        * other application coming in are started by default.
+        */
+       usess->active = 1;
+
        rcu_read_lock();
 
        /*
@@ -4984,6 +5040,10 @@ int ust_app_start_trace_all(struct ltt_ust_session *usess)
         */
        (void) ust_app_clear_quiescent_session(usess);
 
+       cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
+               ust_app_global_update(usess, app);
+       }
+
        cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
                ret = ust_app_start_trace(usess, app);
                if (ret < 0) {
@@ -5009,6 +5069,12 @@ int ust_app_stop_trace_all(struct ltt_ust_session *usess)
 
        DBG("Stopping all UST traces");
 
+       /*
+        * Even though the stop trace might fail, flag this session inactive so
+        * other application coming in are not started by default.
+        */
+       usess->active = 0;
+
        rcu_read_lock();
 
        cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
@@ -5072,6 +5138,9 @@ void ust_app_global_create(struct ltt_ust_session *usess, struct ust_app *app)
                /* App session already created. */
                goto end;
        }
+       if (!usess->active) {
+               goto end;
+       }
        assert(ua_sess);
 
        pthread_mutex_lock(&ua_sess->lock);
@@ -5125,14 +5194,12 @@ void ust_app_global_create(struct ltt_ust_session *usess, struct ust_app *app)
 
        pthread_mutex_unlock(&ua_sess->lock);
 
-       if (usess->active) {
-               ret = ust_app_start_trace(usess, app);
-               if (ret < 0) {
-                       goto error;
-               }
-
-               DBG2("UST trace started for app pid %d", app->pid);
+       ret = ust_app_start_trace(usess, app);
+       if (ret < 0) {
+               goto error;
        }
+
+       DBG2("UST trace started for app pid %d", app->pid);
 end:
        /* Everything went well at this point. */
        return;
@@ -5174,7 +5241,9 @@ void ust_app_global_update(struct ltt_ust_session *usess, struct ust_app *app)
        if (!app->compatible) {
                return;
        }
-
+       if (!usess->active) {
+               return;
+       }
        if (trace_ust_pid_tracker_lookup(usess, app->pid)) {
                ust_app_global_create(usess, app);
        } else {
@@ -5190,6 +5259,9 @@ void ust_app_global_update_all(struct ltt_ust_session *usess)
        struct lttng_ht_iter iter;
        struct ust_app *app;
 
+       if (!usess->active) {
+               return;
+       }
        rcu_read_lock();
        cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
                ust_app_global_update(usess, app);
@@ -5210,6 +5282,10 @@ int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
        struct ust_app_session *ua_sess;
        struct ust_app *app;
 
+       if (!usess->active) {
+               goto end;
+       }
+
        rcu_read_lock();
 
        cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
@@ -5249,6 +5325,7 @@ int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
        }
 
        rcu_read_unlock();
+end:
        return ret;
 }
 
@@ -5963,7 +6040,7 @@ enum lttng_error_code ust_app_snapshot_record(struct ltt_ust_session *usess,
        struct lttng_ht_iter iter;
        struct ust_app *app;
        char pathname[PATH_MAX];
-       struct ltt_session *session;
+       struct ltt_session *session = NULL;
        uint64_t trace_archive_id;
 
        assert(usess);
@@ -6111,6 +6188,9 @@ enum lttng_error_code ust_app_snapshot_record(struct ltt_ust_session *usess,
 
 error:
        rcu_read_unlock();
+       if (session) {
+               session_put(session);
+       }
        return status;
 }