root.nwait.Add(-1)
			unlock(&root.lock)
			break
		}
		// Any semrelease after the cansemacquire knows we're waiting
		// (we set nwait above), so go to sleep.
		root.queue(addr, s, lifo)
		goparkunlock(&root.lock, reason, traceBlockSync, 4+skipframes)
		if s.ticket != 0 || cansemacquire(addr) {
			break
		}
	}
	if s.releasetime > 0 {
		blockevent(s.releasetime-t0, 3+skipframes)
	}
	releaseSudog(s)

	scavenger.wake()

	nextMarkBitArenaEpoch()
}

func bgsweep(c chan int) {
	sweep.g = getg()

	lockInit(&sweep.lock, lockRankSweep)
	lock(&sweep.lock)
	sweep.parked = true
	c <- 1
	goparkunlock(&sweep.lock, waitReasonGCSweepWait, traceBlockGCSweep, 1)

	for {
		// bgsweep attempts to be a "low priority" goroutine by intentionally
		// yielding time. It's OK if it doesn't run, because goroutines allocating

	}
}

// park parks the scavenger goroutine.
func (s *scavengerState) park() {
	lock(&s.lock)
	if getg() != s.g {
		throw("tried to park scavenger from another goroutine")
	}
	s.parked = true
	goparkunlock(&s.lock, waitReasonGCScavengeWait, traceBlockSystemGoroutine, 2)
}

// ready signals to sysmon that the scavenger should be awoken.
func (s *scavengerState) ready() {
	s.sysmonWake.Store(1)
}

		work.assistQueue.q = oldList
		if oldList.tail != 0 {
			oldList.tail.ptr().schedlink.set(nil)
		}
		unlock(&work.assistQueue.lock)
		return false
	}
	// Park.
	goparkunlock(&work.assistQueue.lock, waitReasonGCAssistWait, traceBlockGCMarkAssist, 2)
	return true
}

// gcFlushBgCredit flushes scanWork units of background scan work
// credit. This first satisfies blocked assists on the

			// We're done.
			unlock(&work.sweepWaiters.lock)
			return
		}

		// Wait until sweep termination, mark, and mark
		// termination of cycle N complete.
		work.sweepWaiters.list.push(getg())
		goparkunlock(&work.sweepWaiters.lock, waitReasonWaitForGCCycle, traceBlockUntilGCEnds, 1)
	}
}

// gcMode indicates how concurrent a GC cycle should be.
type gcMode int

const (

	forcegc.g = getg()
	lockInit(&forcegc.lock, lockRankForcegc)
	for {
		lock(&forcegc.lock)
		if forcegc.idle.Load() {
			throw("forcegc: phase error")
		}
		forcegc.idle.Store(true)
		goparkunlock(&forcegc.lock, waitReasonForceGCIdle, traceBlockSystemGoroutine, 1)
		// this goroutine is explicitly resumed by sysmon
		if debug.gctrace > 0 {
			println("GC forced")
		}
		// Time-triggered, fully concurrent.

String id=61
	data="/usr/local/google/home/mknyszek/work/go-1/src/runtime/time.go"
String id=62
	data="main.allocHog"
String id=63
	data="main.cpu10"
String id=64
	data="runtime.goparkunlock"
String id=65
	data="/usr/local/google/home/mknyszek/work/go-1/src/runtime/proc.go"
String id=66
	data="runtime.bgsweep"
String id=67