From 95611c0eb4436102ab0dad3a705acff5f5eb7aca Mon Sep 17 00:00:00 2001 From: Prabhav Dogra Date: Sun, 20 Apr 2025 07:52:58 +0000 Subject: [PATCH] sync: use atomic.Bool for Once.done Updated the use of atomic.Uint32 to atomic.Bool for sync package. Change-Id: Ib8da66fea86ef06e1427ac5118016b96fbcda6b1 GitHub-Last-Rev: d36e0f431fcde988f90badf86bbf04a18a411947 GitHub-Pull-Request: golang/go#73447 Reviewed-on: https://go-review.googlesource.com/c/go/+/666895 Reviewed-by: Junyang Shao Reviewed-by: Keith Randall LUCI-TryBot-Result: Go LUCI Auto-Submit: Keith Randall Reviewed-by: Keith Randall Reviewed-by: Jorropo --- src/sync/once.go | 8 ++++---- test/inline_sync.go | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/src/sync/once.go b/src/sync/once.go index 90840b19b5..1573b28b28 100644 --- a/src/sync/once.go +++ b/src/sync/once.go @@ -25,7 +25,7 @@ type Once struct { // The hot path is inlined at every call site. // Placing done first allows more compact instructions on some architectures (amd64/386), // and fewer instructions (to calculate offset) on other architectures. - done atomic.Uint32 + done atomic.Bool m Mutex } @@ -64,7 +64,7 @@ func (o *Once) Do(f func()) { // This is why the slow path falls back to a mutex, and why // the o.done.Store must be delayed until after f returns. - if o.done.Load() == 0 { + if !o.done.Load() { // Outlined slow-path to allow inlining of the fast-path. o.doSlow(f) } @@ -73,8 +73,8 @@ func (o *Once) Do(f func()) { func (o *Once) doSlow(f func()) { o.m.Lock() defer o.m.Unlock() - if o.done.Load() == 0 { - defer o.done.Store(1) + if !o.done.Load() { + defer o.done.Store(true) f() } } diff --git a/test/inline_sync.go b/test/inline_sync.go index eaa2176d5f..8359aa3aa2 100644 --- a/test/inline_sync.go +++ b/test/inline_sync.go @@ -37,7 +37,7 @@ var once *sync.Once func small7() { // ERROR "can inline small7" // the Do fast path should be inlined - once.Do(small5) // ERROR "inlining call to sync\.\(\*Once\)\.Do" "inlining call to atomic\.\(\*Uint32\)\.Load" + once.Do(small5) // ERROR "inlining call to sync\.\(\*Once\)\.Do" "inlining call to atomic\.\(\*Bool\)\.Load" } var rwmutex *sync.RWMutex