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diff --git a/third_party/rust/crossbeam-utils/src/cache_padded.rs b/third_party/rust/crossbeam-utils/src/cache_padded.rs
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+use core::fmt;
+use core::ops::{Deref, DerefMut};
+
+/// Pads and aligns a value to the length of a cache line.
+///
+/// In concurrent programming, sometimes it is desirable to make sure commonly accessed pieces of
+/// data are not 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 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. On modern Intel architectures, spatial
+/// prefetcher is pulling pairs of 64-byte cache lines at a time, so we pessimistically assume that
+/// cache lines are 128 bytes long.
+///
+/// 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 crossbeam_utils::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 them in
+/// different cache lines so that concurrent threads pushing and popping elements don't invalidate
+/// each other's cache lines:
+///
+/// ```
+/// use crossbeam_utils::CachePadded;
+/// use std::sync::atomic::AtomicUsize;
+///
+/// struct Queue<T> {
+///     head: CachePadded<AtomicUsize>,
+///     tail: CachePadded<AtomicUsize>,
+///     buffer: *mut T,
+/// }
+/// ```
+#[derive(Clone, Copy, Default, Hash, PartialEq, Eq)]
+// 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/
+//
+#[cfg_attr(any(target_arch = "x86_64", target_arch = "aarch64"), repr(align(128)))]
+#[cfg_attr(
+    not(any(target_arch = "x86_64", target_arch = "aarch64")),
+    repr(align(64))
+)]
+pub struct CachePadded<T> {
+    value: T,
+}
+
+unsafe impl<T: Send> Send for CachePadded<T> {}
+unsafe impl<T: Sync> Sync for CachePadded<T> {}
+
+impl<T> CachePadded<T> {
+    /// Pads and aligns a value to the length of a cache line.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use crossbeam_utils::CachePadded;
+    ///
+    /// let padded_value = CachePadded::new(1);
+    /// ```
+    pub const fn new(t: T) -> CachePadded<T> {
+        CachePadded::<T> { value: t }
+    }
+
+    /// Returns the inner value.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use crossbeam_utils::CachePadded;
+    ///
+    /// let padded_value = CachePadded::new(7);
+    /// let value = padded_value.into_inner();
+    /// assert_eq!(value, 7);
+    /// ```
+    pub fn into_inner(self) -> T {
+        self.value
+    }
+}
+
+impl<T> Deref for CachePadded<T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        &self.value
+    }
+}
+
+impl<T> DerefMut for CachePadded<T> {
+    fn deref_mut(&mut self) -> &mut T {
+        &mut self.value
+    }
+}
+
+impl<T: fmt::Debug> fmt::Debug for CachePadded<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("CachePadded")
+            .field("value", &self.value)
+            .finish()
+    }
+}
+
+impl<T> From<T> for CachePadded<T> {
+    fn from(t: T) -> Self {
+        CachePadded::new(t)
+    }
+}