RFR: 8338383: Implement JEP 491: Synchronize Virtual Threads without Pinning [v9]

[Fei Yang]

On Thu, 31 Oct 2024 20:02:31 GMT, Patricio Chilano Mateo <pchilanomate at openjdk.org> wrote:

>> src/hotspot/cpu/riscv/continuationFreezeThaw_riscv.inline.hpp line 273:
>> 
>>> 271:         ? frame_sp + fsize - frame::sender_sp_offset
>>> 272:         // we need to re-read fp because it may be an oop and we might have fixed the frame.
>>> 273:         : *(intptr_t**)(hf.sp() - 2);
>> 
>> Suggestion:
>> 
>>         : *(intptr_t**)(hf.sp() - frame::sender_sp_offset);
>
> Changed.

Note that `frame::sender_sp_offset` is 0 instead of 2 on linux-riscv64, which is different from aarch64 or x86-64. So I think we should revert this change: https://github.com/openjdk/jdk/pull/21565/commits/12213a70c1cf0639555f0f302237fd012549c4dd. @pchilano : Could you please help do that?

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PR Review Comment: https://git.openjdk.org/jdk/pull/21565#discussion_r1826453713