Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 635 insertions, 0 deletions

diff --git a/third_party/rust/cache-padded/.cargo-checksum.json b/third_party/rust/cache-padded/.cargo-checksum.json
new file mode 100644
index 0000000000..fe13a97d87
--- /dev/null
+++ b/third_party/rust/cache-padded/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"CHANGELOG.md":"01efe9c9a75e5a305dac0e12676ed451f746049a825aa86acef0d8ee90742f71","Cargo.toml":"ea55c73cacac2dcc3bdcb2c657e057d9b73214e76f8654799236b13c853e97bd","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"23f18e03dc49df91622fe2a76176497404e46ced8a715d9d2b67a7446571cca3","README.md":"61d450a57f8699dfc1c39e3bb69236f7d10f31f4503b03aa8b2b37b2448b8b69","src/lib.rs":"4bcb45fe37cdca78ba0e403d9e531102c521ad42e9ffd2ecbb154b4509864978","tests/padding.rs":"120cc65d1fcebbdb0ed8b0c287680ede2483e3ab040746e1a3616ffb39d8f414"},"package":"c1db59621ec70f09c5e9b597b220c7a2b43611f4710dc03ceb8748637775692c"}
\ No newline at end of file
diff --git a/third_party/rust/cache-padded/CHANGELOG.md b/third_party/rust/cache-padded/CHANGELOG.md
new file mode 100644
index 0000000000..7ed155bb86
--- /dev/null
+++ b/third_party/rust/cache-padded/CHANGELOG.md
@@ -0,0 +1,15 @@
+# Version 1.2.0
+
+- Improve implementation of `CachePadded`.
+
+# Version 1.1.1
+
+- Forbid unsafe code.
+
+# Version 1.1.0
+
+- Mark `CachePadded::new()` as const fn.
+
+# Version 1.0.0
+
+- Initial version
diff --git a/third_party/rust/cache-padded/Cargo.toml b/third_party/rust/cache-padded/Cargo.toml
new file mode 100644
index 0000000000..cac57bfbb3
--- /dev/null
+++ b/third_party/rust/cache-padded/Cargo.toml
@@ -0,0 +1,22 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies.
+#
+# If you are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+edition = "2018"
+name = "cache-padded"
+version = "1.2.0"
+authors = ["Stjepan Glavina <stjepang@gmail.com>"]
+description = "Prevent false sharing by padding and aligning to the length of a cache line"
+homepage = "https://github.com/smol-rs/cache-padded"
+keywords = ["cache", "padding", "lock-free", "atomic"]
+categories = ["concurrency", "no-std"]
+license = "Apache-2.0 OR MIT"
+repository = "https://github.com/smol-rs/cache-padded"
diff --git a/third_party/rust/cache-padded/LICENSE-APACHE b/third_party/rust/cache-padded/LICENSE-APACHE
new file mode 100644
index 0000000000..16fe87b06e
--- /dev/null
+++ b/third_party/rust/cache-padded/LICENSE-APACHE
@@ -0,0 +1,201 @@
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diff --git a/third_party/rust/cache-padded/LICENSE-MIT b/third_party/rust/cache-padded/LICENSE-MIT
new file mode 100644
index 0000000000..31aa79387f
--- /dev/null
+++ b/third_party/rust/cache-padded/LICENSE-MIT
@@ -0,0 +1,23 @@
+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,
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+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.
diff --git a/third_party/rust/cache-padded/README.md b/third_party/rust/cache-padded/README.md
new file mode 100644
index 0000000000..6dd2b36929
--- /dev/null
+++ b/third_party/rust/cache-padded/README.md
@@ -0,0 +1,79 @@
+# cache-padded
+
+[![Build](https://github.com/smol-rs/cache-padded/workflows/Build%20and%20test/badge.svg)](
+https://github.com/smol-rs/cache-padded/actions)
+[![License](https://img.shields.io/badge/license-Apache--2.0_OR_MIT-blue.svg)](
+https://github.com/smol-rs/cache-padded)
+[![Cargo](https://img.shields.io/crates/v/cache-padded.svg)](
+https://crates.io/crates/cache-padded)
+[![Documentation](https://docs.rs/cache-padded/badge.svg)](
+https://docs.rs/cache-padded)
+
+Prevent false sharing by padding and aligning to the length of a cache line.
+
+In concurrent programming, sometimes it is desirable to make sure commonly accessed shared data
+is not all placed into the same cache line. Updating an atomic value invalides the whole cache
+line it belongs to, which makes the next access to the same cache line slower for other CPU
+cores. Use `CachePadded` to ensure updating one piece of data doesn't invalidate other cached
+data.
+
+## Size and alignment
+
+Cache lines are assumed to be N bytes long, depending on the architecture:
+
+* On x86-64 and aarch64, N = 128.
+* On all others, N = 64.
+
+Note that N is just a reasonable guess and is not guaranteed to match the actual cache line
+length of the machine the program is running on.
+
+The size of `CachePadded<T>` is the smallest multiple of N bytes large enough to accommodate
+a value of type `T`.
+
+The alignment of `CachePadded<T>` is the maximum of N bytes and the alignment of `T`.
+
+## Examples
+
+Alignment and padding:
+
+```rust
+use cache_padded::CachePadded;
+
+let array = [CachePadded::new(1i8), CachePadded::new(2i8)];
+let addr1 = &*array[0] as *const i8 as usize;
+let addr2 = &*array[1] as *const i8 as usize;
+
+assert!(addr2 - addr1 >= 64);
+assert_eq!(addr1 % 64, 0);
+assert_eq!(addr2 % 64, 0);
+```
+
+When building a concurrent queue with a head and a tail index, it is wise to place indices in
+different cache lines so that concurrent threads pushing and popping elements don't invalidate
+each other's cache lines:
+
+```rust
+use cache_padded::CachePadded;
+use std::sync::atomic::AtomicUsize;
+
+struct Queue<T> {
+    head: CachePadded<AtomicUsize>,
+    tail: CachePadded<AtomicUsize>,
+    buffer: *mut T,
+}
+```
+
+## License
+
+Licensed under either of
+
+ * Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+#### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
+dual licensed as above, without any additional terms or conditions.
diff --git a/third_party/rust/cache-padded/src/lib.rs b/third_party/rust/cache-padded/src/lib.rs
new file mode 100644
index 0000000000..4d602cb667
--- /dev/null
+++ b/third_party/rust/cache-padded/src/lib.rs
@@ -0,0 +1,187 @@
+//! Prevent false sharing by padding and aligning to the length of a cache line.
+//!
+//! In concurrent programming, sometimes it is desirable to make sure commonly accessed shared data
+//! is not all placed into the same cache line. Updating an atomic value invalidates the whole cache
+//! line it belongs to, which makes the next access to the same cache line slower for other CPU
+//! cores. Use [`CachePadded`] to ensure updating one piece of data doesn't invalidate other cached
+//! data.
+//!
+//! # Size and alignment
+//!
+//! Cache lines are assumed to be N bytes long, depending on the architecture:
+//!
+//! * On x86-64, aarch64, and powerpc64, N = 128.
+//! * On arm, mips, mips64, and riscv64, N = 32.
+//! * On s390x, N = 256.
+//!
+//! Note that N is just a reasonable guess and is not guaranteed to match the actual cache line
+//! length of the machine the program is running on.
+//!
+//! The size of `CachePadded<T>` is the smallest multiple of N bytes large enough to accommodate
+//! a value of type `T`.
+//!
+//! The alignment of `CachePadded<T>` is the maximum of N bytes and the alignment of `T`.
+//!
+//! # Examples
+//!
+//! Alignment and padding:
+//!
+//! ```
+//! use cache_padded::CachePadded;
+//!
+//! let array = [CachePadded::new(1i8), CachePadded::new(2i8)];
+//! let addr1 = &*array[0] as *const i8 as usize;
+//! let addr2 = &*array[1] as *const i8 as usize;
+//!
+//! assert!(addr2 - addr1 >= 64);
+//! assert_eq!(addr1 % 64, 0);
+//! assert_eq!(addr2 % 64, 0);
+//! ```
+//!
+//! When building a concurrent queue with a head and a tail index, it is wise to place indices in
+//! different cache lines so that concurrent threads pushing and popping elements don't invalidate
+//! each other's cache lines:
+//!
+//! ```
+//! use cache_padded::CachePadded;
+//! use std::sync::atomic::AtomicUsize;
+//!
+//! struct Queue<T> {
+//!     head: CachePadded<AtomicUsize>,
+//!     tail: CachePadded<AtomicUsize>,
+//!     buffer: *mut T,
+//! }
+//! ```
+
+#![no_std]
+#![forbid(unsafe_code)]
+#![warn(missing_docs, missing_debug_implementations, rust_2018_idioms)]
+
+use core::fmt;
+use core::ops::{Deref, DerefMut};
+
+/// Pads and aligns data to the length of a cache line.
+// Starting from Intel's Sandy Bridge, spatial prefetcher is now pulling pairs of 64-byte cache
+// lines at a time, so we have to align to 128 bytes rather than 64.
+//
+// Sources:
+// - https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf
+// - https://github.com/facebook/folly/blob/1b5288e6eea6df074758f877c849b6e73bbb9fbb/folly/lang/Align.h#L107
+//
+// ARM's big.LITTLE architecture has asymmetric cores and "big" cores have 128-byte cache line size.
+//
+// Sources:
+// - https://www.mono-project.com/news/2016/09/12/arm64-icache/
+//
+// powerpc64 has 128-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_ppc64x.go#L9
+#[cfg_attr(
+    any(
+        target_arch = "x86_64",
+        target_arch = "aarch64",
+        target_arch = "powerpc64",
+    ),
+    repr(align(128))
+)]
+// arm, mips, mips64, and riscv64 have 32-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_arm.go#L7
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mips.go#L7
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mipsle.go#L7
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mips64x.go#L9
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_riscv64.go#L7
+#[cfg_attr(
+    any(
+        target_arch = "arm",
+        target_arch = "mips",
+        target_arch = "mips64",
+        target_arch = "riscv64",
+    ),
+    repr(align(32))
+)]
+// s390x has 256-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_s390x.go#L7
+#[cfg_attr(target_arch = "s390x", repr(align(256)))]
+// x86 and wasm have 64-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/dda2991c2ea0c5914714469c4defc2562a907230/src/internal/cpu/cpu_x86.go#L9
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_wasm.go#L7
+//
+// All others are assumed to have 64-byte cache line size.
+#[cfg_attr(
+    not(any(
+        target_arch = "x86_64",
+        target_arch = "aarch64",
+        target_arch = "powerpc64",
+        target_arch = "arm",
+        target_arch = "mips",
+        target_arch = "mips64",
+        target_arch = "riscv64",
+        target_arch = "s390x",
+    )),
+    repr(align(64))
+)]
+#[derive(Clone, Copy, Default, Hash, PartialEq, Eq)]
+pub struct CachePadded<T>(T);
+
+impl<T> CachePadded<T> {
+    /// Pads and aligns a piece of data to the length of a cache line.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use cache_padded::CachePadded;
+    ///
+    /// let padded = CachePadded::new(1);
+    /// ```
+    pub const fn new(t: T) -> CachePadded<T> {
+        CachePadded(t)
+    }
+
+    /// Returns the inner data.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use cache_padded::CachePadded;
+    ///
+    /// let padded = CachePadded::new(7);
+    /// let data = padded.into_inner();
+    /// assert_eq!(data, 7);
+    /// ```
+    pub fn into_inner(self) -> T {
+        self.0
+    }
+}
+
+impl<T> Deref for CachePadded<T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        &self.0
+    }
+}
+
+impl<T> DerefMut for CachePadded<T> {
+    fn deref_mut(&mut self) -> &mut T {
+        &mut self.0
+    }
+}
+
+impl<T: fmt::Debug> fmt::Debug for CachePadded<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_tuple("CachePadded").field(&self.0).finish()
+    }
+}
+
+impl<T> From<T> for CachePadded<T> {
+    fn from(t: T) -> Self {
+        CachePadded::new(t)
+    }
+}
diff --git a/third_party/rust/cache-padded/tests/padding.rs b/third_party/rust/cache-padded/tests/padding.rs
new file mode 100644
index 0000000000..6125854cd9
--- /dev/null
+++ b/third_party/rust/cache-padded/tests/padding.rs
@@ -0,0 +1,107 @@
+use std::cell::Cell;
+use std::mem;
+
+use cache_padded::CachePadded;
+
+#[test]
+fn default() {
+    let x: CachePadded<u64> = Default::default();
+    assert_eq!(*x, 0);
+}
+
+#[test]
+fn store_u64() {
+    let x: CachePadded<u64> = CachePadded::new(17);
+    assert_eq!(*x, 17);
+}
+
+#[test]
+fn store_pair() {
+    let x: CachePadded<(u64, u64)> = CachePadded::new((17, 37));
+    assert_eq!(x.0, 17);
+    assert_eq!(x.1, 37);
+}
+
+#[test]
+fn distance() {
+    let arr = [CachePadded::new(17u8), CachePadded::new(37u8)];
+    let a = &*arr[0] as *const u8;
+    let b = &*arr[1] as *const u8;
+    assert!(unsafe { a.offset(64) } <= b);
+}
+
+#[test]
+fn different_sizes() {
+    CachePadded::new(17u8);
+    CachePadded::new(17u16);
+    CachePadded::new(17u32);
+    CachePadded::new([17u64; 0]);
+    CachePadded::new([17u64; 1]);
+    CachePadded::new([17u64; 2]);
+    CachePadded::new([17u64; 3]);
+    CachePadded::new([17u64; 4]);
+    CachePadded::new([17u64; 5]);
+    CachePadded::new([17u64; 6]);
+    CachePadded::new([17u64; 7]);
+    CachePadded::new([17u64; 8]);
+}
+
+#[test]
+fn large() {
+    let a = [17u64; 9];
+    let b = CachePadded::new(a);
+    assert!(mem::size_of_val(&a) <= mem::size_of_val(&b));
+}
+
+#[test]
+fn debug() {
+    assert_eq!(format!("{:?}", CachePadded::new(17u64)), "CachePadded(17)");
+}
+
+#[test]
+fn drops() {
+    let count = Cell::new(0);
+
+    struct Foo<'a>(&'a Cell<usize>);
+
+    impl<'a> Drop for Foo<'a> {
+        fn drop(&mut self) {
+            self.0.set(self.0.get() + 1);
+        }
+    }
+
+    let a = CachePadded::new(Foo(&count));
+    let b = CachePadded::new(Foo(&count));
+
+    assert_eq!(count.get(), 0);
+    drop(a);
+    assert_eq!(count.get(), 1);
+    drop(b);
+    assert_eq!(count.get(), 2);
+}
+
+#[test]
+fn clone() {
+    let a = CachePadded::new(17);
+    let b = a.clone();
+    assert_eq!(*a, *b);
+}
+
+#[test]
+fn runs_custom_clone() {
+    let count = Cell::new(0);
+
+    struct Foo<'a>(&'a Cell<usize>);
+
+    impl<'a> Clone for Foo<'a> {
+        fn clone(&self) -> Foo<'a> {
+            self.0.set(self.0.get() + 1);
+            Foo::<'a>(self.0)
+        }
+    }
+
+    let a = CachePadded::new(Foo(&count));
+    let _ = a.clone();
+
+    assert_eq!(count.get(), 1);
+}