Fix: lttng-tracepoint module notifier should return NOTIFY_OK

[lttng-modules.git] / lttng-events.c

diff --git a/lttng-events.c b/lttng-events.c
index 48e1760174569e449a330c766a7c3fca3ecba206..0d62f9fb0ae4da6d651008d0e792895accceaa7d 100644 (file)
--- a/lttng-events.c
+++ b/lttng-events.c
@@ -76,7 +76,12 @@ int _lttng_field_statedump(struct lttng_session *session,
 
 void synchronize_trace(void)
 {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,1,0))
+       synchronize_rcu();
+#else
        synchronize_sched();
+#endif
+
 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0))
 #ifdef CONFIG_PREEMPT_RT_FULL
        synchronize_rcu();
@@ -395,6 +400,7 @@ int lttng_event_enable(struct lttng_event *event)
                break;
        case LTTNG_KERNEL_KPROBE:
        case LTTNG_KERNEL_FUNCTION:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_NOOP:
                WRITE_ONCE(event->enabled, 1);
                break;
@@ -430,6 +436,7 @@ int lttng_event_disable(struct lttng_event *event)
                break;
        case LTTNG_KERNEL_KPROBE:
        case LTTNG_KERNEL_FUNCTION:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_NOOP:
                WRITE_ONCE(event->enabled, 0);
                break;
@@ -576,6 +583,7 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                event_name = event_desc->name;
                break;
        case LTTNG_KERNEL_KPROBE:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_KRETPROBE:
        case LTTNG_KERNEL_FUNCTION:
        case LTTNG_KERNEL_NOOP:
@@ -739,6 +747,28 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                        goto register_error;
                }
                break;
+       case LTTNG_KERNEL_UPROBE:
+               /*
+                * Needs to be explicitly enabled after creation, since
+                * we may want to apply filters.
+                */
+               event->enabled = 0;
+               event->registered = 1;
+
+               /*
+                * Populate lttng_event structure before event
+                * registration.
+                */
+               smp_wmb();
+
+               ret = lttng_uprobes_register(event_param->name,
+                               event_param->u.uprobe.fd,
+                               event);
+               if (ret)
+                       goto register_error;
+               ret = try_module_get(event->desc->owner);
+               WARN_ON_ONCE(!ret);
+               break;
        default:
                WARN_ON_ONCE(1);
                ret = -EINVAL;
@@ -801,6 +831,7 @@ void register_event(struct lttng_event *event)
                        desc->name);
                break;
        case LTTNG_KERNEL_KPROBE:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_KRETPROBE:
        case LTTNG_KERNEL_FUNCTION:
        case LTTNG_KERNEL_NOOP:
@@ -850,6 +881,10 @@ int _lttng_event_unregister(struct lttng_event *event)
        case LTTNG_KERNEL_NOOP:
                ret = 0;
                break;
+       case LTTNG_KERNEL_UPROBE:
+               lttng_uprobes_unregister(event);
+               ret = 0;
+               break;
        default:
                WARN_ON_ONCE(1);
        }
@@ -883,6 +918,10 @@ void _lttng_event_destroy(struct lttng_event *event)
        case LTTNG_KERNEL_NOOP:
        case LTTNG_KERNEL_SYSCALL:
                break;
+       case LTTNG_KERNEL_UPROBE:
+               module_put(event->desc->owner);
+               lttng_uprobes_destroy_private(event);
+               break;
        default:
                WARN_ON_ONCE(1);
        }
@@ -1102,8 +1141,8 @@ int lttng_session_list_tracker_pids(struct lttng_session *session)
                ret = PTR_ERR(tracker_pids_list_file);
                goto file_error;
        }
-       if (atomic_long_add_unless(&session->file->f_count,
-               1, INT_MAX) == INT_MAX) {
+       if (!atomic_long_add_unless(&session->file->f_count, 1, LONG_MAX)) {
+               ret = -EOVERFLOW;
                goto refcount_error;
        }
        ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file);
@@ -1432,6 +1471,18 @@ error_free:
        return ret;
 }
 
+int lttng_event_add_callsite(struct lttng_event *event,
+               struct lttng_kernel_event_callsite __user *callsite)
+{
+
+       switch (event->instrumentation) {
+       case LTTNG_KERNEL_UPROBE:
+               return lttng_uprobes_add_callsite(event, callsite);
+       default:
+               return -EINVAL;
+       }
+}
+
 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
                struct lttng_kernel_context *context_param)
 {