Make Quanta crate optional (but enabled by default)

.github/workflows/CIQuantaDisabled.yml

@@ -0,0 +1,84 @@
+name: CI (Quanta disabled)
+
+on:
+  push:
+    paths-ignore:
+    - '.devcontainer/**'
+    - '.gitpod.yml'
+    - '.vscode/**'
+  pull_request:
+    paths-ignore:
+    - '.devcontainer/**'
+    - '.gitpod.yml'
+    - '.vscode/**'
+  schedule:
+    # Run against the last commit on the default branch on Friday at 8pm (UTC?)
+    - cron:  '0 20 * * 5'
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust:
+          - stable
+          - beta
+          - 1.51.0  # MSRV
+          - nightly # For checking minimum version dependencies.
+
+    steps:
+      - name: Checkout Moka
+        uses: actions/checkout@v2
+
+      - name: Install Rust toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: ${{ matrix.rust }}
+          override: true
+          components: rustfmt, clippy
+
+      - uses: Swatinem/rust-cache@v1
+
+      - name: cargo clean
+        uses: actions-rs/cargo@v1
+        with:
+          command: clean
+
+      - name: Downgrade dependencies to minimal versions (Nightly only)
+        uses: actions-rs/cargo@v1
+        if: ${{ matrix.rust == 'nightly' }}
+        with:
+          command: update
+          args: -Z minimal-versions
+
+      - name: Pin some dependencies to specific versions (MSRV only)
+        if: ${{ matrix.rust == '1.51.0' }}
+        # Avoid hashbrown >= v0.12, which requires Rust 2021 edition.
+        run: |
+          cargo update -p dashmap --precise 5.2.0
+          cargo update -p hashbrown --precise 0.11.2
+
+      - name: Build (no quanta feature)
+        uses: actions-rs/cargo@v1
+        with:
+          command: build
+          args: --no-default-features --features atomic64
+
+      - name: Run tests (release, no quanta feature)
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --release --no-default-features --features atomic64
+
+      - name: Run tests (future feature, but no quanta feature)
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --no-default-features --features 'future, atomic64'
+
+      - name: Run tests (dash feature, but no quanta feature)
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --no-default-features --features 'dash, atomic64'

.github/workflows/LinuxCrossCompileTest.yml

@@ -28,11 +28,11 @@ jobs:
           - target: armv7-unknown-linux-musleabihf
           # Platforms without AtomicU64 support.
           - target: armv5te-unknown-linux-musleabi
-            cargo-opts: "--no-default-features"  # Disable atomic64 feature.
+            cargo-opts: "--no-default-features"  # Disable atomic64 and quanta features.
           - target: mips-unknown-linux-musl
-            cargo-opts: "--no-default-features"  # Disable atomic64 feature.
+            cargo-opts: "--no-default-features"  # Disable atomic64 and quanta features.
           - target: mipsel-unknown-linux-musl
-            cargo-opts: "--no-default-features"  # Disable atomic64 feature.
+            cargo-opts: "--no-default-features"  # Disable atomic64 and quanta features.
 
     steps:
       - name: Checkout Moka

CHANGELOG.md

@@ -1,5 +1,16 @@
 # Moka — Change Log
 
+## Version 0.8.3
+
+### Changed
+
+- Make [Quanta crate][quanta-crate] optional (but enabled by default)
+  ([#121][gh-pull-0121])
+    - Quanta v0.9.3 or older may not work correctly on some x86_64 machines where
+      the Time Stamp Counter (TSC) is not synched across the processor cores.
+      ([#119][gh-issue-0119])
+
+
 ## Version 0.8.2
 
 ### Added
@@ -297,16 +308,19 @@ The minimum supported Rust version (MSRV) is now 1.51.0 (2021-03-25).
 <!-- Links -->
 
 [caffeine-git]: https://github.com/ben-manes/caffeine
+[quanta-crate]: https://crates.io/crates/quanta
 
 [resolving-error-on-32bit]: https://github.com/moka-rs/moka#resolving-compile-errors-on-some-32-bit-platforms
 
+[gh-issue-0119]: https://github.com/moka-rs/moka/issues/119/
 [gh-issue-0107]: https://github.com/moka-rs/moka/issues/107/
 [gh-issue-0072]: https://github.com/moka-rs/moka/issues/72/
 [gh-issue-0059]: https://github.com/moka-rs/moka/issues/59/
 [gh-issue-0043]: https://github.com/moka-rs/moka/issues/43/
 [gh-issue-0038]: https://github.com/moka-rs/moka/issues/38/
 [gh-issue-0031]: https://github.com/moka-rs/moka/issues/31/
 
+[gh-pull-0121]: https://github.com/moka-rs/moka/pull/121/
 [gh-pull-0117]: https://github.com/moka-rs/moka/pull/117/
 [gh-pull-0116]: https://github.com/moka-rs/moka/pull/116/
 [gh-pull-0114]: https://github.com/moka-rs/moka/pull/114/

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "moka"
-version = "0.8.2"
+version = "0.8.3"
 edition = "2018"
 rust-version = "1.51"
 
@@ -16,7 +16,7 @@ exclude = [".circleci", ".devcontainer", ".github", ".gitpod.yml", ".vscode"]
 build = "build.rs"
 
 [features]
-default = ["atomic64"]
+default = ["atomic64", "quanta"]
 
 # Enable this feature to use `moka::future::Cache`.
 future = ["async-io", "async-lock", "futures-util"]
@@ -44,7 +44,6 @@ crossbeam-utils = "0.8"
 num_cpus = "1.13"
 once_cell = "1.7"
 parking_lot = "0.12"
-quanta = "0.9.3"
 scheduled-thread-pool = "0.2.5"
 smallvec = "1.8"
 tagptr = "0.2"
@@ -55,6 +54,9 @@ uuid = { version = "0.8", features = ["v4"] }
 # https://github.com/Manishearth/triomphe/pull/5
 triomphe = { version = "0.1", default-features = false }
 
+# Optional dependencies (quanta, enabled by default)
+quanta = { version = "0.9.3", optional = true }
+
 # Optional dependencies (dashmap)
 dashmap = { version = "5.2", optional = true }
 

README.md

@@ -392,6 +392,7 @@ This crate's minimum supported Rust versions (MSRV) are the followings:
 |:-----------|:-------------------:|:-----------:|
 | no feature |                     | Rust 1.51.0 |
 | `atomic64` |       yes           | Rust 1.51.0 |
+| `quanta`   |       yes           | Rust 1.51.0 |
 | `future`   |                     | Rust 1.51.0 |
 | `dash`     |                     | Rust 1.51.0 |
 

src/common.rs

@@ -5,17 +5,8 @@ pub(crate) mod deque;
 pub(crate) mod error;
 pub(crate) mod frequency_sketch;
 pub(crate) mod thread_pool;
-pub(crate) mod unsafe_weak_pointer;
-
-// targe_has_atomic is more convenient but yet unstable (Rust 1.55)
-// https://github.com/rust-lang/rust/issues/32976
-// #[cfg_attr(target_has_atomic = "64", path = "common/time_atomic64.rs")]
-
-#[cfg_attr(feature = "atomic64", path = "common/atomic_time.rs")]
-#[cfg_attr(not(feature = "atomic64"), path = "common/atomic_time_compat.rs")]
-pub(crate) mod atomic_time;
-
 pub(crate) mod time;
+pub(crate) mod unsafe_weak_pointer;
 
 // Note: `CacheRegion` cannot have more than four enum variants. This is because
 // `crate::{sync,unsync}::DeqNodes` uses a `tagptr::TagNonNull<DeqNode<T>, 2>`

src/common/time.rs

@@ -1,13 +1,32 @@
 use std::time::Duration;
 
-pub(crate) type Clock = quanta::Clock;
+// target_has_atomic is more convenient but yet unstable (Rust 1.55)
+// https://github.com/rust-lang/rust/issues/32976
+// #[cfg_attr(target_has_atomic = "64", path = "common/time_atomic64.rs")]
+
+#[cfg_attr(
+    all(feature = "atomic64", feature = "quanta"),
+    path = "time/atomic_time.rs"
+)]
+#[cfg_attr(
+    not(all(feature = "atomic64", feature = "quanta")),
+    path = "time/atomic_time_compat.rs"
+)]
+pub(crate) mod atomic_time;
+
+#[cfg_attr(feature = "quanta", path = "time/clock_quanta.rs")]
+#[cfg_attr(not(feature = "quanta"), path = "time/clock_compat.rs")]
+mod clock;
+
+pub(crate) use clock::Clock;
+
 #[cfg(test)]
-pub(crate) type Mock = quanta::Mock;
+pub(crate) use clock::Mock;
 
-/// a wrapper type over qunta::Instant to force checked additions and prevent
-/// unintentioal overflow. The type preserve the Copy semnatics for the wrapped
+/// a wrapper type over Instant to force checked additions and prevent
+/// unintentional overflow. The type preserve the Copy semantics for the wrapped
 #[derive(PartialEq, PartialOrd, Clone, Copy)]
-pub(crate) struct Instant(pub quanta::Instant);
+pub(crate) struct Instant(pub clock::Instant);
 
 pub(crate) trait CheckedTimeOps {
     fn checked_add(&self, duration: Duration) -> Option<Self>
@@ -16,12 +35,12 @@ pub(crate) trait CheckedTimeOps {
 }
 
 impl Instant {
-    pub(crate) fn new(instant: quanta::Instant) -> Instant {
+    pub(crate) fn new(instant: clock::Instant) -> Instant {
         Instant(instant)
     }
 
     pub(crate) fn now() -> Instant {
-        Instant(quanta::Instant::now())
+        Instant(clock::Instant::now())
     }
 }
 

src/common/atomic_time.rs → src/common/time/atomic_time.rs

@@ -1,6 +1,6 @@
-use std::sync::atomic::{AtomicU64, Ordering};
+use super::Instant;
 
-use super::time::Instant;
+use std::sync::atomic::{AtomicU64, Ordering};
 
 pub(crate) struct AtomicInstant {
     instant: AtomicU64,

src/common/atomic_time_compat.rs → src/common/time/atomic_time_compat.rs

@@ -1,4 +1,5 @@
-use super::time::Instant;
+use super::Instant;
+
 use parking_lot::RwLock;
 
 pub(crate) struct AtomicInstant {

src/common/time/clock_compat.rs

@@ -0,0 +1,50 @@
+use std::{sync::Arc, time::Instant as StdInstant};
+
+#[cfg(test)]
+use std::time::Duration;
+
+use parking_lot::RwLock;
+
+pub(crate) type Instant = StdInstant;
+
+pub(crate) struct Clock {
+    mock: Option<Arc<Mock>>,
+}
+
+impl Clock {
+    #[cfg(test)]
+    pub(crate) fn mock() -> (Clock, Arc<Mock>) {
+        let mock = Arc::new(Mock::default());
+        let clock = Clock {
+            mock: Some(Arc::clone(&mock)),
+        };
+        (clock, mock)
+    }
+
+    pub(crate) fn now(&self) -> Instant {
+        if let Some(mock) = &self.mock {
+            *mock.now.read()
+        } else {
+            StdInstant::now()
+        }
+    }
+}
+
+pub(crate) struct Mock {
+    now: RwLock<Instant>,
+}
+
+impl Default for Mock {
+    fn default() -> Self {
+        Self {
+            now: RwLock::new(StdInstant::now()),
+        }
+    }
+}
+
+#[cfg(test)]
+impl Mock {
+    pub(crate) fn increment(&self, amount: Duration) {
+        *self.now.write() += amount;
+    }
+}

src/common/time/clock_quanta.rs

@@ -0,0 +1,5 @@
+pub(crate) type Clock = quanta::Clock;
+pub(crate) type Instant = quanta::Instant;
+
+#[cfg(test)]
+pub(crate) type Mock = quanta::Mock;

src/dash/base_cache.rs

@@ -2,10 +2,9 @@ use super::{iter::DashMapIter, Iter};
 use crate::{
     common::{
         self,
-        atomic_time::AtomicInstant,
         deque::{DeqNode, Deque},
         frequency_sketch::FrequencySketch,
-        time::{CheckedTimeOps, Clock, Instant},
+        time::{atomic_time::AtomicInstant, CheckedTimeOps, Clock, Instant},
         CacheRegion,
     },
     sync::{

src/lib.rs

@@ -66,6 +66,7 @@
 //! |:-----------|:-------------------:|:-----------:|
 //! | no feature |                     | Rust 1.51.0 |
 //! | `atomic64` |       yes           | Rust 1.51.0 |
+//! | `quanta`   |       yes           | Rust 1.51.0 |
 //! | `future`   |                     | Rust 1.51.0 |
 //! | `dash`     |                     | Rust 1.51.0 |
 //!

src/sync/base_cache.rs

@@ -14,10 +14,9 @@ use super::debug_counters::CacheDebugStats;
 use crate::{
     common::{
         self,
-        atomic_time::AtomicInstant,
         deque::{DeqNode, Deque},
         frequency_sketch::FrequencySketch,
-        time::{CheckedTimeOps, Clock, Instant},
+        time::{atomic_time::AtomicInstant, CheckedTimeOps, Clock, Instant},
         CacheRegion,
     },
     Policy, PredicateError,

src/sync/entry_info.rs

@@ -1,7 +1,7 @@
 use std::sync::atomic::{AtomicBool, AtomicU32, Ordering};
 
 use super::AccessTime;
-use crate::common::{atomic_time::AtomicInstant, time::Instant};
+use crate::common::time::{atomic_time::AtomicInstant, Instant};
 
 pub(crate) struct EntryInfo {
     is_admitted: AtomicBool,