WASI preview 2 output-streams: new backpressure and flushing design #6877

pchickey · 2023-08-21T23:42:01Z

Backpressure design is being revised to take into account that any call with a list<bytes> argument is going to consume the resources of the callee, so the callee has to explicitly permit how much that is allowed to consume.

Flushing is a way to request & observe the completion of a write. Since the write itself is non-blocking it cant report that it failed if that happens after the call is over. the explicit flush call allows the caller to wait for a write (or sequence of writes) to produce an error, or guarantee that it succeeded.

Fixes #6811

This PR changes the wit interfaces, therefore we are leaving it as a draft until after WasmCon & Componentize the World (Sept 6-8) so that wasmtime's main reflects a consistent set of interfaces for demos and hacking at those events.

We plan to merge this PR to main on Monday, Sept 11. We will then backport it as a cherry-pick to the 13.0 release branch so that these changes get included in the wasmtime 13 release as well.

crates/wasi-preview1-component-adapter/src/lib.rs

crates/wasi/src/preview2/filesystem.rs

crates/wasi/src/preview2/tcp.rs

crates/wasi/src/preview2/pipe.rs

* Use `command::add_to_linker` in tests to reduce the number of times all the `add_to_linker` are listed. * Add all `wasi:sockets` interfaces currently implemented to both the sync and async `command` functions (this enables all the interfaces in the CLI for example). * Use `tokio::net::TcpStream::try_io` whenever I/O is performed on a socket, ensuring that readable/writable flags are set/cleared appropriately (otherwise once readable a socket is infinitely readable). * Add a `with_ambient_tokio_runtime` helper function to use when creating a `tokio::net::TcpStream` since otherwise it panics due to a lack of active runtime in a synchronous context. * Add `WouldBlock` handling to return a 0-length read. * Add an `--inherit-network` CLI flag to enable basic usage of sockets in the CLI. This will conflict a small amount with bytecodealliance#6877 but should be easy to resolve, and otherwise this targets different usability points/issues than that PR.

* Use `command::add_to_linker` in tests to reduce the number of times all the `add_to_linker` are listed. * Add all `wasi:sockets` interfaces currently implemented to both the sync and async `command` functions (this enables all the interfaces in the CLI for example). * Use `tokio::net::TcpStream::try_io` whenever I/O is performed on a socket, ensuring that readable/writable flags are set/cleared appropriately (otherwise once readable a socket is infinitely readable). * Add a `with_ambient_tokio_runtime` helper function to use when creating a `tokio::net::TcpStream` since otherwise it panics due to a lack of active runtime in a synchronous context. * Add `WouldBlock` handling to return a 0-length read. * Add an `--inherit-network` CLI flag to enable basic usage of sockets in the CLI. This will conflict a small amount with #6877 but should be easy to resolve, and otherwise this targets different usability points/issues than that PR.

alexcrichton

This all looks great to me, thanks again so much for pushing on this @pchickey and @elliottt!

I've got a number of minor comments but everything looks great 👍

crates/wasi/src/preview2/filesystem.rs

crates/wasi/src/preview2/host/io.rs

crates/wasi/src/preview2/pipe.rs

crates/wasi/src/preview2/stdio.rs

crates/wasi/src/preview2/stream.rs

crates/wasi/src/preview2/tcp.rs

…6950) * Enhance `async` configuration of `bindgen!` macro (#6942) This commit takes a leaf out of `wiggle`'s book to enable bindings generation for async host functions where only some host functions are async instead of all of them. This enhances the `async` key with a few more options: async: { except_imports: ["foo"], only_imports: ["bar"], } This is beyond what `wiggle` supports where either an allow-list or deny-list can be specified (although only one can be specified). This can be useful if either the list of sync imports or the list of async imports is small. * cranelift-interpreter: Fix SIMD shifts and rotates (#6939) * cranelift-interpreter: Fix SIMD `ishl`/`{s,u}`shr * fuzzgen: Enable a few more ops * cranelift: Fix tests for {u,s}shr * fuzzgen: Change pattern matching arms for shifts Co-Authored-By: Jamey Sharp <[email protected]> --------- Co-authored-by: Jamey Sharp <[email protected]> * Partially revert CLI argument changes from #6737 (#6944) * Partially revert CLI argument changes from #6737 This commit is a partial revert of #6737. That change was reverted in #6830 for the 12.0.0 release of Wasmtime and otherwise it's currently slated to get released with the 13.0.0 release of Wasmtime. Discussion at today's Wasmtime meeting concluded that it's best to couple this change with #6925 as a single release rather than spread out across multiple releases. This commit is thus the revert of #6737, although it's a partial revert in that I've kept many of the new tests added to showcase the differences before/after when the change lands. This means that Wasmtime 13.0.0 will exhibit the same CLI behavior as 12.0.0 and all prior releases. The 14.0.0 release will have both a new CLI and new argument passing semantics. I'll revert this revert (aka re-land #6737) once the 13.0.0 release branch is created and `main` becomes 14.0.0. * Update release notes * riscv64: Use `PCRelLo12I` relocation on Loads (#6938) * riscv64: Use `PCRelLo12I` relocation on Loads * riscv64: Strenghten pattern matching when emitting Load's * riscv64: Clarify some of the load address logic * riscv64: Even stronger matching * Update Rust in CI to 1.72.0, clarify Wasmtime's MSRV (#6900) * Update Rust in CI to 1.72.0 * Update CI, tooling, and docs for MSRV This commit codifies an MSRV policy for Wasmtime at "stable minus two" meaning that the latest three releases of Rust will be supported. This is enforced on CI with a full test suite job running on Linux x86_64 with the minimum supported Rust version. The full test suite will use the latest stable version. A downside of this approach is that new changes may break MSRV support on non-Linux or non-x86_64 platforms and we won't know about it, but that's deemed a minor enough risk at this time. A minor fix is applied to Wasmtime's `Cargo.toml` to support Rust 1.70.0 instead of requiring Rust 1.71.0 * Fix installation of rust * Scrape MSRV from Cargo.toml * Cranelift is the same as Wasmtime's MSRV now, more words too * Fix a typo * aarch64: Use `RegScaled*` addressing modes (#6945) This commit adds a few cases to `amode` construction on AArch64 for using the `RegScaled*` variants of `AMode`. This won't affect wasm due to this only matching the sign-extension happening before the shift, but it should otherwise help non-wasm Cranelift use cases. Closes #6742 * cranelift: Validate `iconst` ranges (#6850) * cranelift: Validate `iconst` ranges Add the following checks: `iconst.i8` immediate must be within 0 .. 2^8-1 `iconst.i16` immediate must be within 0 .. 2^16-1 `iconst.i32` immediate must be within 0 .. 2^32-1 Resolves #3059 * cranelift: Parse `iconst` according to its type Modifies the parser for textual CLIF so that V in `iconst.T V` is parsed according to T. Before this commit, something like `iconst.i32 0xffff_ffff_ffff` was valid because all `iconst` were parsed the same as an `iconst.i64`. Now the above example will throw an error. Also, a negative immediate as in `iconst.iN -X` is now converted to `2^N - X`. This commit also fixes some broken tests. * cranelift: Update tests to match new CLIF parser * Some minor fixes and features for WASI and sockets (#6948) * Use `command::add_to_linker` in tests to reduce the number of times all the `add_to_linker` are listed. * Add all `wasi:sockets` interfaces currently implemented to both the sync and async `command` functions (this enables all the interfaces in the CLI for example). * Use `tokio::net::TcpStream::try_io` whenever I/O is performed on a socket, ensuring that readable/writable flags are set/cleared appropriately (otherwise once readable a socket is infinitely readable). * Add a `with_ambient_tokio_runtime` helper function to use when creating a `tokio::net::TcpStream` since otherwise it panics due to a lack of active runtime in a synchronous context. * Add `WouldBlock` handling to return a 0-length read. * Add an `--inherit-network` CLI flag to enable basic usage of sockets in the CLI. This will conflict a small amount with #6877 but should be easy to resolve, and otherwise this targets different usability points/issues than that PR. --------- Co-authored-by: Afonso Bordado <[email protected]> Co-authored-by: Jamey Sharp <[email protected]> Co-authored-by: Timothée Jourde <[email protected]>

Co-authored-by: Pat Hickey <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Dan Gohman <[email protected]> Stop testing pseudocode Restructure when notifications are sent, and make sure to flush the writer Fix the wasi-http module versions of flush and blocking_flush Use blocking_write_and_flush for blocking writes in the adapters Fix a warning in wasi-http Remove an unused DropPollable add comment explaining try_write for tcpstream refactor: separate struct for representing TcpReadStream by factoring into HostTcpSocket a little bit tcp read stream: handle stream closing tcp tests: use blocking_read where its expecting to wait for input move common test body into wasi-sockets-tests/src/lib.rs ensure parent socket outlives pollable input and output streams can be children now tcp's streams are the sockets children tcp.wit: document child relationships tcp tests: fix to drop socket after its child streams review feedback: propogate worker task panic style error source fix tcp: use preview2::spawn, and propogate worker panics join handle await always propogates panic background task handles ewouldblock as well document choice of constant

…6948) * Use `command::add_to_linker` in tests to reduce the number of times all the `add_to_linker` are listed. * Add all `wasi:sockets` interfaces currently implemented to both the sync and async `command` functions (this enables all the interfaces in the CLI for example). * Use `tokio::net::TcpStream::try_io` whenever I/O is performed on a socket, ensuring that readable/writable flags are set/cleared appropriately (otherwise once readable a socket is infinitely readable). * Add a `with_ambient_tokio_runtime` helper function to use when creating a `tokio::net::TcpStream` since otherwise it panics due to a lack of active runtime in a synchronous context. * Add `WouldBlock` handling to return a 0-length read. * Add an `--inherit-network` CLI flag to enable basic usage of sockets in the CLI. This will conflict a small amount with bytecodealliance#6877 but should be easy to resolve, and otherwise this targets different usability points/issues than that PR.

* doc: document `HostOutputStream` Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]> * fix(wasi): fail when `MemoryOutputStream` buffer is full Signed-off-by: Roman Volosatovs <[email protected]> --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]>

This reverts commit 8ac6781.

With the merging of bytecodealliance#6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

This was removed in bytecodealliance#6195 but re-added in bytecodealliance#6877, I believe by accident, so this re-deletes it. I've also edited `.gitmodules` a bit while I was here to remove it and additionally keep other entries up-to-date with matching paths.

…6877) * Stream backpressure v2 Co-authored-by: Pat Hickey <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Dan Gohman <[email protected]> Stop testing pseudocode Restructure when notifications are sent, and make sure to flush the writer Fix the wasi-http module versions of flush and blocking_flush Use blocking_write_and_flush for blocking writes in the adapters Fix a warning in wasi-http Remove an unused DropPollable add comment explaining try_write for tcpstream refactor: separate struct for representing TcpReadStream by factoring into HostTcpSocket a little bit tcp read stream: handle stream closing tcp tests: use blocking_read where its expecting to wait for input move common test body into wasi-sockets-tests/src/lib.rs ensure parent socket outlives pollable input and output streams can be children now tcp's streams are the sockets children tcp.wit: document child relationships tcp tests: fix to drop socket after its child streams review feedback: propogate worker task panic style error source fix tcp: use preview2::spawn, and propogate worker panics join handle await always propogates panic background task handles ewouldblock as well document choice of constant * sync wit notes into wasi-http * improve wit docs for output-stream * doc: document `HostOutputStream` (#6980) * doc: document `HostOutputStream` Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]> * fix(wasi): fail when `MemoryOutputStream` buffer is full Signed-off-by: Roman Volosatovs <[email protected]> --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]> * rustfmt prtest:full * windows and doc fixes * cli test wasi-http: use blocking-write-and-flush * Disable some tests, and adjust timeouts when running under qemu * Try to reproduce the riscv64 failures * Update riscv to LLVM 17 with beta rust * Revert "Try to reproduce the riscv64 failures" This reverts commit 8ac6781. * Pin the beta version for riscv64 * Fix a warning on nightly --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Roman Volosatovs <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Alex Crichton <[email protected]>

With the merging of #6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

This was removed in #6195 but re-added in #6877, I believe by accident, so this re-deletes it. I've also edited `.gitmodules` a bit while I was here to remove it and additionally keep other entries up-to-date with matching paths.

With the merging of #6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

This was removed in #6195 but re-added in #6877, I believe by accident, so this re-deletes it. I've also edited `.gitmodules` a bit while I was here to remove it and additionally keep other entries up-to-date with matching paths.

…13.0 (#7009) * WASI preview 2 output-streams: new backpressure and flushing design (#6877) * Stream backpressure v2 Co-authored-by: Pat Hickey <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Dan Gohman <[email protected]> Stop testing pseudocode Restructure when notifications are sent, and make sure to flush the writer Fix the wasi-http module versions of flush and blocking_flush Use blocking_write_and_flush for blocking writes in the adapters Fix a warning in wasi-http Remove an unused DropPollable add comment explaining try_write for tcpstream refactor: separate struct for representing TcpReadStream by factoring into HostTcpSocket a little bit tcp read stream: handle stream closing tcp tests: use blocking_read where its expecting to wait for input move common test body into wasi-sockets-tests/src/lib.rs ensure parent socket outlives pollable input and output streams can be children now tcp's streams are the sockets children tcp.wit: document child relationships tcp tests: fix to drop socket after its child streams review feedback: propogate worker task panic style error source fix tcp: use preview2::spawn, and propogate worker panics join handle await always propogates panic background task handles ewouldblock as well document choice of constant * sync wit notes into wasi-http * improve wit docs for output-stream * doc: document `HostOutputStream` (#6980) * doc: document `HostOutputStream` Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]> * fix(wasi): fail when `MemoryOutputStream` buffer is full Signed-off-by: Roman Volosatovs <[email protected]> --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]> * rustfmt prtest:full * windows and doc fixes * cli test wasi-http: use blocking-write-and-flush * Disable some tests, and adjust timeouts when running under qemu * Try to reproduce the riscv64 failures * Update riscv to LLVM 17 with beta rust * Revert "Try to reproduce the riscv64 failures" This reverts commit 8ac6781. * Pin the beta version for riscv64 * Fix a warning on nightly --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Roman Volosatovs <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Alex Crichton <[email protected]> * Un-ignore now-passing test With the merging of #6877 prints to stdout with preview2 should now work without requiring extra sleeps or such. * Remove submodule re-added by accident This was removed in #6195 but re-added in #6877, I believe by accident, so this re-deletes it. I've also edited `.gitmodules` a bit while I was here to remove it and additionally keep other entries up-to-date with matching paths. * add to release notes --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Roman Volosatovs <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Alex Crichton <[email protected]>

…ytecodealliance#6877) * Stream backpressure v2 Co-authored-by: Pat Hickey <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Dan Gohman <[email protected]> Stop testing pseudocode Restructure when notifications are sent, and make sure to flush the writer Fix the wasi-http module versions of flush and blocking_flush Use blocking_write_and_flush for blocking writes in the adapters Fix a warning in wasi-http Remove an unused DropPollable add comment explaining try_write for tcpstream refactor: separate struct for representing TcpReadStream by factoring into HostTcpSocket a little bit tcp read stream: handle stream closing tcp tests: use blocking_read where its expecting to wait for input move common test body into wasi-sockets-tests/src/lib.rs ensure parent socket outlives pollable input and output streams can be children now tcp's streams are the sockets children tcp.wit: document child relationships tcp tests: fix to drop socket after its child streams review feedback: propogate worker task panic style error source fix tcp: use preview2::spawn, and propogate worker panics join handle await always propogates panic background task handles ewouldblock as well document choice of constant * sync wit notes into wasi-http * improve wit docs for output-stream * doc: document `HostOutputStream` (bytecodealliance#6980) * doc: document `HostOutputStream` Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]> * fix(wasi): fail when `MemoryOutputStream` buffer is full Signed-off-by: Roman Volosatovs <[email protected]> --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Pat Hickey <[email protected]> * rustfmt prtest:full * windows and doc fixes * cli test wasi-http: use blocking-write-and-flush * Disable some tests, and adjust timeouts when running under qemu * Try to reproduce the riscv64 failures * Update riscv to LLVM 17 with beta rust * Revert "Try to reproduce the riscv64 failures" This reverts commit 8ac6781. * Pin the beta version for riscv64 * Fix a warning on nightly --------- Signed-off-by: Roman Volosatovs <[email protected]> Co-authored-by: Roman Volosatovs <[email protected]> Co-authored-by: Trevor Elliott <[email protected]> Co-authored-by: Alex Crichton <[email protected]>

With the merging of bytecodealliance#6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

This was removed in bytecodealliance#6195 but re-added in bytecodealliance#6877, I believe by accident, so this re-deletes it. I've also edited `.gitmodules` a bit while I was here to remove it and additionally keep other entries up-to-date with matching paths.

github-actions bot added the wasi Issues pertaining to WASI label Aug 22, 2023

elliottt force-pushed the pch/backpressure_2 branch from f0d7497 to fa19703 Compare August 23, 2023 20:52

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alexcrichton mentioned this pull request Aug 30, 2023

Should blocking functions be enhanced or removed? WebAssembly/wasi-io#44

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Some minor fixes and features for WASI and sockets #6948

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Pat Hickey added 2 commits September 1, 2023 10:37

sync wit notes into wasi-http

5319934

improve wit docs for output-stream

a97a676

pchickey mentioned this pull request Sep 1, 2023

New backpressure and flushing scheme for output-stream WebAssembly/wasi-io#45

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eduardomourar mentioned this pull request Sep 5, 2023

feat(wasmtime-cli): restore support for wasi http module #6878

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Merge remote-tracking branch 'origin/main' into pch/backpressure_2

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pchickey marked this pull request as ready for review September 11, 2023 15:56

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pchickey enabled auto-merge September 11, 2023 18:34

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Try to reproduce the riscv64 failures

8ac6781

elliottt force-pushed the pch/backpressure_2 branch from ea2f7bb to 8ac6781 Compare September 11, 2023 23:27

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elliottt force-pushed the pch/backpressure_2 branch from 58738fa to 8ac6781 Compare September 12, 2023 15:57

alexcrichton and others added 4 commits September 12, 2023 08:57

Update riscv to LLVM 17 with beta rust

521c51e

Revert "Try to reproduce the riscv64 failures"

b3f5863

This reverts commit 8ac6781.

Pin the beta version for riscv64

e6ff96f

Fix a warning on nightly

8b0899e

elliottt added this pull request to the merge queue Sep 12, 2023

Merged via the queue into main with commit a0469b1 Sep 12, 2023
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elliottt deleted the pch/backpressure_2 branch September 12, 2023 18:14

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Un-ignore now-passing test #7007

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Un-ignore now-passing test

422ea7c

With the merging of bytecodealliance#6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

alexcrichton mentioned this pull request Sep 12, 2023

Remove submodule re-added by accident #7008

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Un-ignore now-passing test

a4a49a9

With the merging of #6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

pchickey mentioned this pull request Sep 12, 2023

[release-13.0] Backport stream backpressure and associated fixups to 13.0 #7009

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Un-ignore now-passing test (#7007)

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With the merging of #6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

eduardomourar pushed a commit to eduardomourar/wasmtime that referenced this pull request Sep 13, 2023

Un-ignore now-passing test (bytecodealliance#7007)

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With the merging of bytecodealliance#6877 prints to stdout with preview2 should now work without requiring extra sleeps or such.

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WASI preview 2 output-streams: new backpressure and flushing design #6877

WASI preview 2 output-streams: new backpressure and flushing design #6877

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WASI preview 2 output-streams: new backpressure and flushing design #6877

WASI preview 2 output-streams: new backpressure and flushing design #6877

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