Allow specifying orderings when loading/storing AtomicCpuSets

kernel/src/sched/sched_class/mod.rs

@@ -3,7 +3,7 @@
 #![warn(unused)]
 
 use alloc::{boxed::Box, sync::Arc};
-use core::fmt;
+use core::{fmt, sync::atomic::Ordering};
 
 use ostd::{
     arch::read_tsc as sched_clock,
@@ -263,7 +263,7 @@ impl ClassScheduler {
         }
         debug_assert!(flags == EnqueueFlags::Spawn);
         let guard = disable_local();
-        let affinity = thread.atomic_cpu_affinity().load();
+        let affinity = thread.atomic_cpu_affinity().load(Ordering::Relaxed);
         let mut selected = guard.current_cpu();
         let mut minimum_load = u32::MAX;
         let last_chosen = match self.last_chosen_cpu.get() {

kernel/src/syscall/sched_affinity.rs

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MPL-2.0
 
-use core::{cmp, mem};
+use core::{cmp, mem, sync::atomic::Ordering};
 
 use ostd::cpu::{num_cpus, CpuId, CpuSet};
 
@@ -14,9 +14,9 @@ pub fn sys_sched_getaffinity(
     ctx: &Context,
 ) -> Result<SyscallReturn> {
     let cpu_set = match tid {
-        0 => ctx.thread.atomic_cpu_affinity().load(),
+        0 => ctx.thread.atomic_cpu_affinity().load(Ordering::Relaxed),
         _ => match thread_table::get_thread(tid) {
-            Some(thread) => thread.atomic_cpu_affinity().load(),
+            Some(thread) => thread.atomic_cpu_affinity().load(Ordering::Relaxed),
             None => return Err(Error::with_message(Errno::ESRCH, "thread does not exist")),
         },
     };
@@ -39,10 +39,15 @@ pub fn sys_sched_setaffinity(
     let user_cpu_set = read_cpu_set_from(ctx.user_space(), cpuset_size, cpu_set_ptr)?;
 
     match tid {
-        0 => ctx.thread.atomic_cpu_affinity().store(&user_cpu_set),
+        0 => ctx
+            .thread
+            .atomic_cpu_affinity()
+            .store(&user_cpu_set, Ordering::Relaxed),
         _ => match thread_table::get_thread(tid) {
             Some(thread) => {
-                thread.atomic_cpu_affinity().store(&user_cpu_set);
+                thread
+                    .atomic_cpu_affinity()
+                    .store(&user_cpu_set, Ordering::Relaxed);
             }
             None => return Err(Error::with_message(Errno::ESRCH, "thread does not exist")),
         },