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package seccheck
import (
"unsafe"
"gvisor.dev/gvisor/pkg/gohacks"
"gvisor.dev/gvisor/pkg/sync"
)
// SeqAtomicLoad returns a copy of *ptr, ensuring that the read does not race
// with any writer critical sections in seq.
//
//go:nosplit
func SeqAtomicLoadCheckerSlice(seq *sync.SeqCount, ptr *[]Checker) []Checker {
for {
if val, ok := SeqAtomicTryLoadCheckerSlice(seq, seq.BeginRead(), ptr); ok {
return val
}
}
}
// SeqAtomicTryLoad returns a copy of *ptr while in a reader critical section
// in seq initiated by a call to seq.BeginRead() that returned epoch. If the
// read would race with a writer critical section, SeqAtomicTryLoad returns
// (unspecified, false).
//
//go:nosplit
func SeqAtomicTryLoadCheckerSlice(seq *sync.SeqCount, epoch sync.SeqCountEpoch, ptr *[]Checker) (val []Checker, ok bool) {
if sync.RaceEnabled {
gohacks.Memmove(unsafe.Pointer(&val), unsafe.Pointer(ptr), unsafe.Sizeof(val))
} else {
val = *ptr
}
ok = seq.ReadOk(epoch)
return
}
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