feat(maitake): introduce a separate maitake-sync crate (#462)

The `maitake` crate provides async synchronization primitives in a
`maitake::sync` module. These APIs don't require the rest of the
runtime, and would be nice to be able to use in other crates. `maitake`
is not yet published to crates.io, as it contains Git-only dependencies.
However, the `sync` module can be implemented entirely using published
code, and therefore, a crate containing only `maitake::sync` could be
published.

This branch introduces a new `maitake-sync` crate, containing the
synchronization primitives from `maitake::sync`. The `maitake::sync`
module now re-exports `maitake-sync`, so there should be no impact for
existing uses of the crate. The new `maitake-sync` crate can easily be
published to crates.io, and depended on from released code.

.github/workflows/ci.yml

@@ -59,6 +59,8 @@ jobs:
             maitake:
               paths:
                 - 'maitake/**/*.rs'
+                - 'maitake-sync/**/*.rs'
+                - 'maitake-sync/Cargo.toml'
                 - 'maitake/Cargo.toml'
                 - '.github/workflows/ci.yml'
                 - 'justfile'
@@ -275,8 +277,10 @@ jobs:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     - name: install nextest
       uses: taiki-e/install-action@nextest
-    - name: run loom tests
+    - name: run loom tests (maitake)
       run: just loom maitake
+    - name: run loom tests (maitake-sync)
+      run: just loom maitake-sync
 
   ### mycelium-util ###
 

Cargo.toml

@@ -8,6 +8,7 @@ members = [
     "hal-x86_64",
     "inoculate",
     "maitake",
+    "maitake-sync",
     "mycotest",
     "trace",
     "pci",

cordyceps/Cargo.toml

@@ -30,7 +30,7 @@ tracing-subscriber = { version = "0.3", features = ["fmt"] }
 pin-project = "1"
 
 [target.'cfg(loom)'.dependencies]
-loom = "0.5.5"
+loom = "0.7"
 tracing = { version = "0.1" }
 
 [package.metadata.docs.rs]

maitake-sync/Cargo.toml

@@ -0,0 +1,58 @@
+[package]
+name = "maitake-sync"
+version = "0.1.0"
+authors = [
+    "Eliza Weisman <[email protected]>",
+]
+description = "No-std async synchronization primitives from Maitake"
+repository = "https://github.com/hawkw/mycelium"
+documentation = "https://docs.rs/maitake-sync"
+homepage = "https://mycelium.elizas.website"
+license = "MIT"
+readme = "README.md"
+keywords = ["async", "no_std", "sync", "mutex", "rwlock"]
+categories = [
+    "no-std",
+    "async",
+    "concurrency"
+]
+edition = "2021"
+rust-version = "1.61.0"
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[features]
+default = ["alloc"]
+alloc = ["cordyceps/alloc"]
+no-cache-pad = ["cordyceps/no-cache-pad"]
+core-error = []
+
+[dependencies]
+mycelium-bitfield = { version = "0.1.3", path = "../bitfield" }
+cordyceps = { version = "0.3.0", path = "../cordyceps" }
+pin-project = "1"
+portable-atomic = "1.2"
+tracing = { version = "0.1", default_features = false, optional = true }
+
+# this is a normal dependency, rather than a dev dependency, so that
+# `maitake-sync` may be used in other crates' loom tests as well (but only when
+# the cfg is enabled).
+[target.'cfg(loom)'.dependencies]
+loom = { version = "0.7", default_features = false }
+
+[dev-dependencies]
+futures-util = "0.3"
+futures = "0.3"
+tokio-test = "0.4"
+tracing = { version = "0.1", default_features = false, features = ["std"] }
+tracing-subscriber = { version = "0.3.11", features = ["fmt", "env-filter"] }
+
+[target.'cfg(not(loom))'.dev-dependencies]
+proptest = "1"
+tokio = { version = "1.32", features = ["rt", "macros"] }
+
+[target.'cfg(loom)'.dev-dependencies]
+loom = { version = "0.7", features = ["futures", "checkpoint"] }
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]

maitake-sync/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Eliza Weisman
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.