Version 2.7.7

[lttng-modules.git] / probes / lttng-kretprobes.c

diff --git a/probes/lttng-kretprobes.c b/probes/lttng-kretprobes.c
index d71090a2bc321edcac3695c774508c1d0d025655..10bb52ffb1c2c915603ab9a4563e806ee3665a9d 100644 (file)
--- a/probes/lttng-kretprobes.c
+++ b/probes/lttng-kretprobes.c
@@ -219,9 +219,9 @@ int lttng_kretprobes_register(const char *name,
         * unregistered. Same for memory allocation.
         */
        kref_init(&lttng_krp->kref_alloc);
-       kref_get(&lttng_krp->kref_alloc);       /* inc refcount to 2 */
+       kref_get(&lttng_krp->kref_alloc);       /* inc refcount to 2, no overflow. */
        kref_init(&lttng_krp->kref_register);
-       kref_get(&lttng_krp->kref_register);    /* inc refcount to 2 */
+       kref_get(&lttng_krp->kref_register);    /* inc refcount to 2, no overflow. */
 
        /*
         * Ensure the memory we just allocated don't trigger page faults.
@@ -285,6 +285,26 @@ void lttng_kretprobes_destroy_private(struct lttng_event *event)
 }
 EXPORT_SYMBOL_GPL(lttng_kretprobes_destroy_private);
 
+int lttng_kretprobes_event_enable_state(struct lttng_event *event,
+               int enable)
+{
+       struct lttng_event *event_return;
+       struct lttng_krp *lttng_krp;
+
+       if (event->instrumentation != LTTNG_KERNEL_KRETPROBE) {
+               return -EINVAL;
+       }
+       if (event->enabled == enable) {
+               return -EBUSY;
+       }
+       lttng_krp = event->u.kretprobe.lttng_krp;
+       event_return = lttng_krp->event[EVENT_RETURN];
+       ACCESS_ONCE(event->enabled) = enable;
+       ACCESS_ONCE(event_return->enabled) = enable;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(lttng_kretprobes_event_enable_state);
+
 MODULE_LICENSE("GPL and additional rights");
 MODULE_AUTHOR("Mathieu Desnoyers");
 MODULE_DESCRIPTION("Linux Trace Toolkit Kretprobes Support");