Commit Graph

3 Commits

Author SHA1 Message Date
Pat Hickey
8b4bdf92e2 make ResourceLimiter operate on Store data; add hooks for entering and exiting native code (#2952)
* wasmtime_runtime: move ResourceLimiter defaults into this crate

In preparation of changing wasmtime::ResourceLimiter to be a re-export
of this definition, because translating between two traits was causing
problems elsewhere.

* wasmtime: make ResourceLimiter a re-export of wasmtime_runtime::ResourceLimiter

* refactor Store internals to support ResourceLimiter as part of store's data

* add hooks for entering and exiting native code to Store

* wasmtime-wast, fuzz: changes to adapt ResourceLimiter API

* fix tests

* wrap calls into wasm with entering/exiting exit hooks as well

* the most trivial test found a bug, lets write some more

* store: mark some methods as #[inline] on Store, StoreInner, StoreInnerMost

Co-authored-By: Alex Crichton <alex@alexcrichton.com>

* improve tests for the entering/exiting native hooks

Co-authored-by: Alex Crichton <alex@alexcrichton.com>
2021-06-08 09:37:00 -05:00
Alex Crichton
7a1b7cdf92 Implement RFC 11: Redesigning Wasmtime's APIs (#2897)
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.
2021-06-03 09:10:53 -05:00
Peter Huene
f12b4c467c Add resource limiting to the Wasmtime API. (#2736)
* Add resource limiting to the Wasmtime API.

This commit adds a `ResourceLimiter` trait to the Wasmtime API.

When used in conjunction with `Store::new_with_limiter`, this can be used to
monitor and prevent WebAssembly code from growing linear memories and tables.

This is particularly useful when hosts need to take into account host resource
usage to determine if WebAssembly code can consume more resources.

A simple `StaticResourceLimiter` is also included with these changes that will
simply limit the size of linear memories or tables for all instances created in
the store based on static values.

* Code review feedback.

* Implemented `StoreLimits` and `StoreLimitsBuilder`.
* Moved `max_instances`, `max_memories`, `max_tables` out of `Config` and into
  `StoreLimits`.
* Moved storage of the limiter in the runtime into `Memory` and `Table`.
* Made `InstanceAllocationRequest` use a reference to the limiter.
* Updated docs.
* Made `ResourceLimiterProxy` generic to remove a level of indirection.
* Fixed the limiter not being used for `wasmtime::Memory` and
  `wasmtime::Table`.

* Code review feedback and bug fix.

* `Memory::new` now returns `Result<Self>` so that an error can be returned if
  the initial requested memory exceeds any limits placed on the store.

* Changed an `Arc` to `Rc` as the `Arc` wasn't necessary.

* Removed `Store` from the `ResourceLimiter` callbacks. Custom resource limiter
  implementations are free to capture any context they want, so no need to
  unnecessarily store a weak reference to `Store` from the proxy type.

* Fixed a bug in the pooling instance allocator where an instance would be
  leaked from the pool. Previously, this would only have happened if the OS was
  unable to make the necessary linear memory available for the instance. With
  these changes, however, the instance might not be created due to limits
  placed on the store. We now properly deallocate the instance on error.

* Added more tests, including one that covers the fix mentioned above.

* Code review feedback.

* Add another memory to `test_pooling_allocator_initial_limits_exceeded` to
  ensure a partially created instance is successfully deallocated.
* Update some doc comments for better documentation of `Store` and
  `ResourceLimiter`.
2021-04-19 09:19:20 -05:00