// and this way we can allow write barriers in the
		// panic path.
		getg().m.p.ptr().wbBuf.discard()
		return
	}

	// Switch to the system stack so we don't have to worry about
	// safe points.
	systemstack(func() {
		wbBufFlush1(getg().m.p.ptr())
	})
}

// wbBufFlush1 flushes p's write barrier buffer to the GC work queue.
//
// This must not have write barriers because it is part of the write

// newcoro creates a new coro containing a
// goroutine blocked waiting to run f
// and returns that coro.
func newcoro(f func(*coro)) *coro {
	c := new(coro)
	c.f = f
	pc := getcallerpc()
	gp := getg()
	systemstack(func() {
		mp := gp.m
		start := corostart
		startfv := *(**funcval)(unsafe.Pointer(&start))
		gp = newproc1(startfv, gp, pc, true, waitReasonCoroutine)

		// Scribble down locked thread state if needed and/or donate

// has completed and that there are no more writers to it.
func traceCPUFlush(gen uintptr) {
	// Flush any remaining trace buffers containing CPU samples.
	if buf := trace.cpuBuf[gen%2]; buf != nil {
		systemstack(func() {
			lock(&trace.lock)
			traceBufFlush(buf, gen)
			unlock(&trace.lock)
			trace.cpuBuf[gen%2] = nil
		})
	}
}

// traceCPUSample writes a CPU profile sample stack to the execution tracer's