twice.
</p>

<h3 id="atomic">Atomic Values</h3>

<p>
The APIs in the <a href="/pkg/sync/atomic/"><code>sync/atomic</code></a>
package are collectively “atomic operations”
that can be used to synchronize the execution of different goroutines.
If the effect of an atomic operation <i>A</i> is observed by atomic operation <i>B</i>,
then <i>A</i> is synchronized before <i>B</i>.

func (p *ProxyMetric) add(p2 ProxyMetric) {
	atomic.AddUint64(&p.GetTotal, p2.GetTotal)
	atomic.AddUint64(&p.HeadTotal, p2.HeadTotal)
	atomic.AddUint64(&p.GetTagTotal, p2.GetTagTotal)
	atomic.AddUint64(&p.PutTagTotal, p2.PutTagTotal)
	atomic.AddUint64(&p.RmvTagTotal, p2.RmvTagTotal)
	atomic.AddUint64(&p.GetFailedTotal, p2.GetFailedTotal)
	atomic.AddUint64(&p.HeadFailedTotal, p2.HeadFailedTotal)

func GetRPCStats() RPCStats {
	s := RPCStats{
		Errs:     atomic.LoadUint64(&globalStats.errs),
		DialErrs: atomic.LoadUint64(&globalStats.tcpDialErrs),
	}
	if v := atomic.LoadUint64(&globalStats.tcpDialCount); v > 0 {
		s.DialAvgDuration = atomic.LoadUint64(&globalStats.tcpDialTotalDur) / v
		s.TTFBAvgDuration = atomic.LoadUint64(&globalStats.tcpTimeForFirstByteTotalDur) / v
	}
	return s
}

    outer:
    while (true) {
      AtomicLong atomic = map.get(key);
      if (atomic == null) {
        atomic = map.putIfAbsent(key, new AtomicLong(delta));
        if (atomic == null) {
          return delta;
        }
        // atomic is now non-null; fall through
      }

      while (true) {
        long oldValue = atomic.get();
        if (oldValue == 0L) {

	serverStats := ServerHTTPStats{}
	serverStats.S3RequestsIncoming = atomic.SwapUint64(&st.s3RequestsIncoming, 0)
	serverStats.S3RequestsInQueue = atomic.LoadInt32(&st.s3RequestsInQueue)
	serverStats.TotalS3RejectedAuth = atomic.LoadUint64(&st.rejectedRequestsAuth)
	serverStats.TotalS3RejectedTime = atomic.LoadUint64(&st.rejectedRequestsTime)
	serverStats.TotalS3RejectedHeader = atomic.LoadUint64(&st.rejectedRequestsHeader)

pkg sync/atomic, method (*Uintptr) Load() uintptr #50860
pkg sync/atomic, method (*Uintptr) Store(uintptr) #50860
pkg sync/atomic, method (*Uintptr) Swap(uintptr) uintptr #50860
pkg sync/atomic, type Bool struct #50860
pkg sync/atomic, type Int32 struct #50860
pkg sync/atomic, type Int64 struct #50860
pkg sync/atomic, type Pointer[$0 interface{}] struct #50860
pkg sync/atomic, type Uint32 struct #50860

import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.LockSupport;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;

pkg sync/atomic, func OrUint32(*uint32, uint32) uint32 #61395
pkg sync/atomic, func OrUint64(*uint64, uint64) uint64 #61395
pkg sync/atomic, func OrUintptr(*uintptr, uintptr) uintptr #61395
pkg sync/atomic, method (*Int32) And(int32) int32 #61395
pkg sync/atomic, method (*Int32) Or(int32) int32 #61395
pkg sync/atomic, method (*Int64) And(int64) int64 #61395
pkg sync/atomic, method (*Int64) Or(int64) int64 #61395

		duration := time.Since(startTime)

		atomic.AddUint64(&p.operations[s], 1)
		if s < scannerMetricLastRealtime {
			p.latency[s].addSize(duration, int64(sz))
		}
	}
}

// incTime will increment time on metric s with a specific duration.
// Use for s < scannerMetricLastRealtime
func (p *scannerMetrics) incTime(s scannerMetric, d time.Duration) {
	atomic.AddUint64(&p.operations[s], 1)

func (l *Init) Do(f func() error) error {
	if atomic.LoadUint32(&l.done) == 0 {
		return l.do(f)
	}
	return nil
}

func (l *Init) do(f func() error) error {
	l.m.Lock()
	defer l.m.Unlock()
	if atomic.LoadUint32(&l.done) == 0 {
		if err := f(); err != nil {
			return err
		}
		// Mark as done only when f() is successful
		atomic.StoreUint32(&l.done, 1)
	}
	return nil
}