Bug: `IS_INIT.compare_exchange` uses stronger memory ordering than necessary

[zjp-CN]

percpu/percpu/src/imp.rs

Line 59 in 89c8a54

.compare_exchange(false, true, Ordering::SeqCst, Ordering::SeqCst)

This is caught by AtomVChecker :

{
  "bug_kind": "AtomicCorrelationViolation",
  "possibility": "Possibly",
  "diagnosis": {
    "atomic": "percpu/src/imp.rs:59:10: 59:75"
  },
  "explanation": "Using an atomic operation with a stronger memory ordering than necessary can lead to unnecessary performance overhead.
   Using Relaxed is sufficient to ensure the correctness of the program"
}

Report

Report from os-checker & AtomVChecker:

[equation314]

Thanks for figuring this issue, but since init is not a frequent operation, it has little impact on performance.