In an effort to simplify the many fuel related APIs, simplify the
interface here to a single counter with get and set methods.
Additionally the async yield is reduced to an interval of the total fuel
instead of injecting fuel, so it's easy to still reason about how much
fuel is left even with yielding turned on.
Internally this works by keeping two counters - one the VM uses to
increment towards 0 for fuel, the other to track how much is in
"reserve". Then when we're out of gas, we pull from the reserve to
refuel and continue. We use the reserve in two cases: one for overflow
of the fuel (which is an i64 and the API expresses fuel as u64) and the
other for async yieling, which then the yield interval acts as a cap to
how much we can refuel with.
This also means that `get_fuel` can return the full range of `u64`
before this change it could only return up to `i64::MAX`. This is
important because this PR is removing the functionality to track fuel
consumption, and this makes the API less error prone for embedders to
track consumption themselves.
Careful to note that the VM counter that is stored as `i64` can be
positive if an instruction "costs" multiple units of fuel when the fuel
ran out.
prtest:full
Signed-off-by: Tyler Rockwood <rockwood@redpanda.com>
* Remove explicit `S` type parameters
This commit removes the explicit `S` type parameter on `Func::typed` and
`Instance::get_typed_func`. Historical versions of Rust required that
this be a type parameter but recent rustcs support a mixture of explicit
type parameters and `impl Trait`. This removes, at callsites, a
superfluous `, _` argument which otherwise never needs specification.
* Fix mdbook examples
* Add cmake compatibility to c-api
* Add CMake documentation to wasmtime.h
* Add CMake instructions in examples
* Modify CI for CMake support
* Use correct rust in CI
* Trigger build
* Refactor run-examples
* Reintroduce example_to_run in run-examples
* Replace run-examples crate with cmake
* Fix markdown formatting in examples readme
* Fix cmake test quotes
* Build rust wasm before cmake tests
* Pass CTEST_OUTPUT_ON_FAILURE
* Another cmake test
* Handle os differences in cmake test
* Fix bugs in memory and multimemory examples
* Upgrade all crates to the Rust 2021 edition
I've personally started using the new format strings for things like
`panic!("some message {foo}")` or similar and have been upgrading crates
on a case-by-case basis, but I think it probably makes more sense to go
ahead and blanket upgrade everything so 2021 features are always
available.
* Fix compile of the C API
* Fix a warning
* Fix another warning
* Change the injection count of fuel in a store from u32 to u64
This commit updates the type of the amount of times to inject fuel in
the `out_of_fuel_async_yield` to `u64` instead of `u32`. This should
allow effectively infinite fuel to get injected, even if a small amount
of fuel is injected per iteration.
Closes#2927Closes#3046
* Fix tokio example
Implement Wasmtime's new API as designed by RFC 11. This is quite a large commit which has had lots of discussion externally, so for more information it's best to read the RFC thread and the PR thread.
* wasmtime-wasi: re-exporting this WasiCtxBuilder was shadowing the right one
wasi-common's WasiCtxBuilder is really only useful wasi_cap_std_sync and
wasi_tokio to implement their own Builder on top of.
This re-export of wasi-common's is 1. not useful and 2. shadow's the
re-export of the right one in sync::*.
* wasi-common: eliminate WasiCtxBuilder, make the builder methods on WasiCtx instead
* delete wasi-common::WasiCtxBuilder altogether
just put those methods directly on &mut WasiCtx.
As a bonus, the sync and tokio WasiCtxBuilder::build functions
are no longer fallible!
* bench fixes
* more test fixes
Tyler Rockwood
Alex Crichton
TheGreatRambler
Pat Hickey
Pat Hickey