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package time
import (
"strings"
"unsafe"
"fmt"
"gvisor.dev/gvisor/pkg/sync"
"reflect"
)
// SeqAtomicLoad returns a copy of *ptr, ensuring that the read does not race
// with any writer critical sections in seq.
//
//go:nosplit
func SeqAtomicLoadParameters(seq *sync.SeqCount, ptr *Parameters) Parameters {
for {
if val, ok := SeqAtomicTryLoadParameters(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 SeqAtomicTryLoadParameters(seq *sync.SeqCount, epoch sync.SeqCountEpoch, ptr *Parameters) (val Parameters, ok bool) {
if sync.RaceEnabled {
sync.Memmove(unsafe.Pointer(&val), unsafe.Pointer(ptr), unsafe.Sizeof(val))
} else {
val = *ptr
}
ok = seq.ReadOk(epoch)
return
}
func initParameters() {
var val Parameters
typ := reflect.TypeOf(val)
name := typ.Name()
if ptrs := sync.PointersInType(typ, name); len(ptrs) != 0 {
panic(fmt.Sprintf("SeqAtomicLoad<%s> is invalid since values %s of type %s contain pointers:\n%s", typ, name, typ, strings.Join(ptrs, "\n")))
}
}
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