On Mon, 2 Jun 2025 14:57:47 GMT, Markus Grönlund <mgron...@openjdk.org> wrote:
>> Johannes Bechberger has updated the pull request incrementally with one
>> additional commit since the last revision:
>>
>> Fix bug related to async stack walking
>
> src/hotspot/share/jfr/jfr.inline.hpp line 41:
>
>> 39: inline void Jfr::check_and_process_sample_request(JavaThread* jt) {
>> 40: JfrThreadLocal* tl = jt->jfr_thread_local();
>> 41: bool has_cpu_time_sample_request = tl->has_cpu_time_jfr_requests();
>
> Why this change?
So I don't read the ` tl->has_cpu_time_jfr_requests()` twice on the hot-path
> src/hotspot/share/jfr/periodic/sampling/jfrCPUTimeThreadSampler.cpp line 349:
>
>> 347: const frame top_frame = thread->last_frame();
>> 348: bool in_continuation = is_in_continuation(top_frame, thread);
>> 349: for (u4 i = 0; i < queue.size(); i++) {
>
> Realized this drainage is entirely wrong!
>
> You are not using the sample requests in the queue to build individual stack
> traces for events; instead, you are using the same top frame (the last Java
> frame) for all of them.
Can I export compute_top_frame and use it here?
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/25302#discussion_r2121424752
PR Review Comment: https://git.openjdk.org/jdk/pull/25302#discussion_r2121413413
