// Update heapLive and heapScan.
	gcController.update(dHeapLive, scanAlloc)
}

// prepareForSweep flushes c if the system has entered a new sweep phase
// since c was populated. This must happen between the sweep phase
// starting and the first allocation from c.
func (c *mcache) prepareForSweep() {
	// Alternatively, instead of making sure we do this on every P

	// of additional memory might be held onto.
	//
	// Also, flush the pinner cache, to avoid leaking that memory
	// indefinitely.
	forEachP(waitReasonFlushProcCaches, func(pp *p) {
		pp.mcache.prepareForSweep()
		if pp.status == _Pidle {
			systemstack(func() {
				lock(&mheap_.lock)
				pp.pcache.flush(&mheap_.pages)
				unlock(&mheap_.lock)
			})
		}
		pp.pinnerCache = nil
	})

	}

	gp := getg()
	if gp.m.p != 0 && gp.m.p.ptr().id < nprocs {
		// continue to use the current P
		gp.m.p.ptr().status = _Prunning
		gp.m.p.ptr().mcache.prepareForSweep()
	} else {
		// release the current P and acquire allp[0].
		//
		// We must do this before destroying our current P
		// because p.destroy itself has write barriers, so we