e := n.entry()
		for e != nil {
			if !yield(e.key, e.value) {
				return false
			}
			e = e.overflow.Load()
		}
	}
	return true
}

const (
	// 16 children. This seems to be the sweet spot for
	// load performance: any smaller and we lose out on
	// 50% or more in CPU performance. Any larger and the
	// returns are minuscule (~1% improvement for 32 children).
	nChildrenLog2 = 4

	mSyscallID int64

	// maySweep indicates the sweep events should be traced.
	// This is used to defer the sweep start event until a span
	// has actually been swept.
	maySweep bool

	// inSweep indicates that at least one sweep event has been traced.
	inSweep bool

	// swept and reclaimed track the number of bytes swept and reclaimed
	// by sweeping in the current sweep loop (while maySweep was true).
	swept, reclaimed uintptr
}

	// to sweep N.
	//
	// 2. In sweep N, help with sweep N.
	//
	// At this point we can begin a full cycle N+1.
	//
	// 3. Trigger cycle N+1 by starting sweep termination N+1.
	//
	// 4. Wait for mark termination N+1 to complete.
	//
	// 5. Help with sweep N+1 until it's done.
	//
	// This all has to be written to deal with the fact that the
	// GC may move ahead on its own. For example, when we block

	EvSTWStart          = 9  // GC mark termination start [timestamp, kind]
	EvSTWDone           = 10 // GC mark termination done [timestamp]
	EvGCSweepStart      = 11 // GC sweep start [timestamp, stack id]
	EvGCSweepDone       = 12 // GC sweep done [timestamp, swept, reclaimed]
	EvGoCreate          = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]

	// access (since that may free the backing store).
	allspans []*mspan // all spans out there

	// Proportional sweep
	//
	// These parameters represent a linear function from gcController.heapLive
	// to page sweep count. The proportional sweep system works to
	// stay in the black by keeping the current page sweep count
	// above this line at the current gcController.heapLive.
	//

	EvGCBegin            // GC start [timestamp, seq, stack ID]
	EvGCEnd              // GC done [timestamp, seq]
	EvGCSweepActive      // GC sweep active [timestamp, P ID]
	EvGCSweepBegin       // GC sweep start [timestamp, stack ID]
	EvGCSweepEnd         // GC sweep done [timestamp, swept bytes, reclaimed bytes]
	EvGCMarkAssistActive // GC mark assist active [timestamp, goroutine ID]

	// hits a traceAcquire, it sees that the trace is enabled.
	//
	// Note also that stopping the world is necessary to make sure sweep-related events are
	// coherent. Since the world is stopped and sweeps are non-preemptible, we can never start
	// the world and see an unpaired sweep 'end' event. Other parts of the tracer rely on this.
	stw := stopTheWorld(stwStartTrace)

	EvSTWDone           event.Type = 10 // GC mark termination done [timestamp]
	EvGCSweepStart      event.Type = 11 // GC sweep start [timestamp, stack id]
	EvGCSweepDone       event.Type = 12 // GC sweep done [timestamp, swept, reclaimed]
	EvGoCreate          event.Type = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]

		r.Name = "GC concurrent mark phase"
		r.Scope = ResourceID{Kind: ResourceNone}
	case go122.EvGCSweepBegin, go122.EvGCSweepActive, go122.EvGCSweepEnd:
		r.Name = "GC incremental sweep"
		r.Scope = ResourceID{Kind: ResourceProc}
		if e.base.typ == go122.EvGCSweepActive {
			r.Scope.id = int64(e.base.args[0])
		} else {
			r.Scope.id = int64(e.Proc())
		}
		r.Scope.id = int64(e.Proc())

					break
				}
				// This G has been in a mark assist *and running on its P* since the start
				// of the trace.
				fallthrough
			case handleSweep(r):
				// This P has been in sweep (or mark assist, from above) in the start of the trace.
				//
				// We don't need to do anything if UtilPerProc is set. If we get an event like