RFR: 8253064: monitor list simplifications and getting rid of TSM [v6]

[Daniel D.Daugherty]

On Wed, 11 Nov 2020 04:50:52 GMT, David Holmes <dholmes at openjdk.org> wrote:

>> Daniel D. Daugherty has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   resolve more robehn and coleenp comments.
>
> src/hotspot/share/runtime/synchronizer.cpp line 153:
> 
>> 151:     if (self->is_Java_thread()) {
>> 152:       // A JavaThread must check for a safepoint/handshake and honor it.
>> 153:       ObjectSynchronizer::chk_for_block_req(self->as_Java_thread(), "unlinking",
> 
> I won't disapprove but this is a case where refactoring is IMO worse than code duplication. Logging parameters should not be a part of this API IMO.

At this point, the refactoring has grown on me. I like the fact that
it reduces the "noise" in those three functions.

> src/hotspot/share/runtime/synchronizer.cpp line 1228:
> 
>> 1226:       os::naked_short_sleep(999);  // sleep for almost 1 second
>> 1227:     } else {
>> 1228:       os::naked_short_sleep(999);  // sleep for almost 1 second
> 
> So this block can now just be:
> 
>> if (self->is_Java_thread()) {
>>     ThreadBlockInVM tbivm(self->as_Java_thread());
>> }
>> os::naked_short_sleep(999);  // sleep for almost 1 second

As @robehn pointed out, I screwed up that change because
I lost the block over duration of the sleep. I've reverted that
change to the original.

-------------

PR: https://git.openjdk.java.net/jdk/pull/642