broker_tokio/loom/std/
atomic_u64.rs

1//! Implementation of an atomic u64 cell. On 64 bit platforms, this is a
2//! re-export of `AtomicU64`. On 32 bit platforms, this is implemented using a
3//! `Mutex`.
4
5pub(crate) use self::imp::AtomicU64;
6
7// `AtomicU64` can only be used on targets with `target_has_atomic` is 64 or greater.
8// Once `cfg_target_has_atomic` feature is stable, we can replace it with
9// `#[cfg(target_has_atomic = "64")]`.
10// Refs: https://github.com/rust-lang/rust/tree/master/src/librustc_target
11#[cfg(not(any(target_arch = "arm", target_arch = "mips", target_arch = "powerpc")))]
12mod imp {
13    pub(crate) use std::sync::atomic::AtomicU64;
14}
15
16#[cfg(any(target_arch = "arm", target_arch = "mips", target_arch = "powerpc"))]
17mod imp {
18    use std::sync::atomic::Ordering;
19    use std::sync::Mutex;
20
21    #[derive(Debug)]
22    pub(crate) struct AtomicU64 {
23        inner: Mutex<u64>,
24    }
25
26    impl AtomicU64 {
27        pub(crate) fn new(val: u64) -> AtomicU64 {
28            AtomicU64 {
29                inner: Mutex::new(val),
30            }
31        }
32
33        pub(crate) fn load(&self, _: Ordering) -> u64 {
34            *self.inner.lock().unwrap()
35        }
36
37        pub(crate) fn store(&self, val: u64, _: Ordering) {
38            *self.inner.lock().unwrap() = val;
39        }
40
41        pub(crate) fn fetch_or(&self, val: u64, _: Ordering) -> u64 {
42            let mut lock = self.inner.lock().unwrap();
43            let prev = *lock;
44            *lock = prev | val;
45            prev
46        }
47
48        pub(crate) fn compare_and_swap(&self, old: u64, new: u64, _: Ordering) -> u64 {
49            let mut lock = self.inner.lock().unwrap();
50            let prev = *lock;
51
52            if prev != old {
53                return prev;
54            }
55
56            *lock = new;
57            prev
58        }
59    }
60}
broker_tokio/loom/std/atomic_u64.rs

broker_tokio/loom/std/
atomic_u64.rs
