Stream: git-wasmtime

Topic: wasmtime / PR #10206 threads: add feature flags

Wasmtime GitHub notifications bot (Feb 07 2025 at 19:51):

abrown opened PR #10206 from abrown:set-feature-flags to bytecodealliance:main:

This adds both the Cargo-level and CLI-level flags for the shared-everything-threads proposal. We may not want to expose this feature just yet, but I need a place to park this since the stack of commits to enable shared-everything threads is getting out of hand. The feedback I'm look for is: what we should be gating with this new Cargo feature?

Wasmtime GitHub notifications bot (Feb 07 2025 at 22:44):

github-actions[bot] commented on PR #10206:

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Wasmtime GitHub notifications bot (Feb 09 2025 at 17:55):

alexcrichton commented on PR #10206:

What do you think about using the preexisting threads Cargo feature for this? That's mostly avoiding runtime deps of threads/libstd/etc and having that gate both threads and shared-everything-threads seems reasonable to me

Wasmtime GitHub notifications bot (Feb 09 2025 at 17:57):

alexcrichton commented on PR #10206:

Oh and do directly answer this:

The feedback I'm look for is: what we should be gating with this new Cargo feature?

I wrote up some basic thoughts here but the tl;dr; IMO is "anything that requires a runtime dependency" aka something outside of libcore. In that sense the current threads proposal is gated because it requires mutexes/etc to implement atomic notify/wait. I don't think that shared-everything-threads will require any more than threads, though, but any nontrivial dependency above the core crate should be gated.

(or do you have specific things you're curious about too?)

Wasmtime GitHub notifications bot (Apr 10 2025 at 22:26):

abrown updated PR #10206.

Wasmtime GitHub notifications bot (Apr 10 2025 at 22:29):

abrown commented on PR #10206:

The latest commits remove the CLI flags since we probably don't want to expose that yet to users _and_ adopt @alexcrichton's suggestion to use the threads Cargo feature instead of creating a new, specialized shared-everything-threads feature. What is now added is all the internal flag bits necessary for running WAST tests, the absence of which is one blocker to #10518. I'm going to alter the PR message to reflect this so we get a more accurate commit message in the Git history.

Wasmtime GitHub notifications bot (Apr 10 2025 at 22:32):

abrown edited PR #10206:

This change adds the minimal, internal flags necessary for testing the shared-everything-threads proposal. It chooses to skip the user-facing CLI flags for now and, as suggested, keeps the Cargo threads feature as the sole feature flag gating compilation of threads-related code, which will eventually include shared-everything-threads.

Wasmtime GitHub notifications bot (Apr 10 2025 at 22:32):

abrown has marked PR #10206 as ready for review.

Wasmtime GitHub notifications bot (Apr 10 2025 at 22:32):

abrown requested fitzgen for a review on PR #10206.

Wasmtime GitHub notifications bot (Apr 10 2025 at 22:32):

abrown requested wasmtime-fuzz-reviewers for a review on PR #10206.

Wasmtime GitHub notifications bot (Apr 10 2025 at 22:32):

abrown requested wasmtime-core-reviewers for a review on PR #10206.

Wasmtime GitHub notifications bot (Apr 10 2025 at 23:45):

github-actions[bot] commented on PR #10206:

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Wasmtime GitHub notifications bot (Apr 11 2025 at 14:42):

alexcrichton submitted PR review:

Technically this won't actually work if the test actually used shared-everything-threads in the sense that this block needs to be updated for fuzzing to propagate the need of shared-everything-threads to wasmtime::Config, and that's going through CLI flags which means this'll also have to add -Wshared-everything-threads.

That being said such a change is a superset of what you've got here, and this seems fine otherwise.

Wasmtime GitHub notifications bot (Apr 11 2025 at 18:55):

abrown merged PR #10206.

Last updated: Apr 17 2025 at 01:31 UTC