Replaced WFE instruction with ISB in mi_atomic_yield on ARM64 #1215
+1
−1
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
… Windows as it significantly improves performance
Collaborator
|
Interesting PR. Mmm, it would be best if we didn't need atomic yield at all :-( Anyways, in v3 there is (almost) no use of atomic yield so that improves matters. In the other cases, the atomic yield is really used to signify that another thread needs to make progress for the current thread to advance. As such ISB (essentially a memory barrier) doesn't quite do that? WFE (wait for another thread event) seems more appropiate .. but then, you are seeing improved perfomance? Is that on v2 ? |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Replaced WFE instruction with ISB in mi_atomic_yield on ARM64 for non Windows as it significantly improves performance.
Also on one closed platform I ported mimalloc to, WFE resulted in an application freeze, because no even was generated to wake threads that were waiting with WFE