RFR: 8338383: Implementation of Synchronize Virtual Threads without Pinning [v3]

[Alan Bateman]

On Tue, 22 Oct 2024 07:28:05 GMT, David Holmes <dholmes at openjdk.org> wrote:

>> Patricio Chilano Mateo has updated the pull request incrementally with six additional commits since the last revision:
>> 
>>  - Fix comments in objectMonitor.hpp
>>  - Move frame::saved_thread_address() to platform dependent files
>>  - Fix typo in jvmtiExport.cpp
>>  - remove usage of frame::metadata_words in possibly_adjust_frame()
>>  - Fix comments in c2 locking paths
>>  - Revert and simplify changes to c1_Runtime1 on aarch64 and riscv
>
> src/java.base/share/classes/java/lang/VirtualThread.java line 115:
> 
>> 113:      *   RUNNING -> WAITING        // transitional state during wait on monitor
>> 114:      *   WAITING -> WAITED         // waiting on monitor
>> 115:      *    WAITED -> BLOCKED        // notified, waiting to be unblocked by monitor owner
> 
> Waiting to re-enter the monitor?

yes

> src/java.base/share/classes/java/lang/VirtualThread.java line 178:
> 
>> 176:     // timed-wait support
>> 177:     private long waitTimeout;
>> 178:     private byte timedWaitNonce;
> 
> Strange name - what does this mean?

Sequence number, nouce, anything will work here as it's just to deal with the scenario where the timeout task for a previous wait may run concurrently with a subsequent wait.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/21565#discussion_r1810579901
PR Review Comment: https://git.openjdk.org/jdk/pull/21565#discussion_r1810583267