On Tue, 24 May 2022 22:23:59 GMT, Alex Menkov <[email protected]> wrote:
>> Serguei Spitsyn has updated the pull request incrementally with one
>> additional commit since the last revision:
>>
>> add extra test coverage for JVMTI extension events:
>> VirtualThreadMount/VirtualThreadUnmount
>
> src/hotspot/share/prims/jvmtiEventController.cpp line 775:
>
>> 773: env->set_event_callbacks(callbacks, size_of_callbacks);
>> 774: // Mask to clear normal event bits.
>> 775: const jlong CLEARING_MASK = (1L >> (JVMTI_MIN_EVENT_TYPE_VAL -
>> TOTAL_MIN_EVENT_TYPE_VAL)) - 1L;
>
> I don't follow how this works..
> Should it be "<<" instead of ">>" ?
Maybe it would be clearer to turn off the bits when there are no events:
jlong enabled_bits =
env->env_event_enable()->_event_callback_enabled.get_bits();
for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei)
{
jvmtiEvent evt_t = (jvmtiEvent)ei;
if (!env->has_callback(evt_t)) {
// clear the bit if there is no callback
enabled_bits &= ~JvmtiEventEnabled::bit_for(evt_t);
}
}
-------------
PR: https://git.openjdk.java.net/jdk/pull/8860