return old;
}
-static void tracepoint_update_call(struct tracepoint *tp, struct tracepoint_func *tp_funcs)
+static void tracepoint_update_call(struct tracepoint *tp, struct tracepoint_func *tp_funcs, bool sync)
{
void *func = tp->iterator;
if (!tp->static_call_key)
return;
- if (!tp_funcs[1].func)
+ if (!tp_funcs[1].func) {
func = tp_funcs[0].func;
+ /*
+ * If going from the iterator back to a single caller,
+ * we need to synchronize with __DO_TRACE to make sure
+ * that the data passed to the callback is the one that
+ * belongs to that callback.
+ */
+ if (sync)
+ tracepoint_synchronize_unregister();
+ }
__static_call_update(tp->static_call_key, tp->static_call_tramp, func);
}
* include/linux/tracepoint.h using rcu_dereference_sched().
*/
rcu_assign_pointer(tp->funcs, tp_funcs);
- tracepoint_update_call(tp, tp_funcs);
+ tracepoint_update_call(tp, tp_funcs, false);
static_key_enable(&tp->key);
release_probes(old);
tp->unregfunc();
static_key_disable(&tp->key);
+ rcu_assign_pointer(tp->funcs, tp_funcs);
} else {
- tracepoint_update_call(tp, tp_funcs);
+ rcu_assign_pointer(tp->funcs, tp_funcs);
+ tracepoint_update_call(tp, tp_funcs,
+ tp_funcs[0].func != old[0].func);
}
-
- rcu_assign_pointer(tp->funcs, tp_funcs);
release_probes(old);
return 0;
}