gcPercentGoal = (gcPercentGoal + uint64(physPageSize) - 1) &^ (uint64(physPageSize) - 1)

	// Represents where we are now in the heap's contribution to RSS in bytes.
	//
	// Guaranteed to always be a multiple of physPageSize on systems where
	// physPageSize <= pageSize since we map new heap memory at a size larger than
	// any physPageSize and released memory in multiples of the physPageSize.
	//

// vdsoMarker reports whether PC is on the VDSO page.
//
//go:nosplit
func inVDSOPage(pc uintptr) bool {
	for _, k := range vdsoSymbolKeys {
		if *k.ptr != 0 {
			page := *k.ptr &^ (physPageSize - 1)
			return pc >= page && pc < page+physPageSize
		}
	}
	return false

// None of the Go runtime is initialized.
//
//go:nosplit
//go:nowritebarrierrec
func libpreinit() {
	initsig(true)
}

func osinit() {
	ncpu = getncpu()
	if physPageSize == 0 {
		physPageSize = getPageSize()
	}
}

var urandom_dev = []byte("/dev/urandom\x00")

//go:nosplit
func readRandom(r []byte) int {
	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)

	// This should be around 12 KiB or less.
	totalSize := uintptr(0)
	for l := 0; l < summaryLevels; l++ {
		totalSize += (uintptr(1) << (heapAddrBits - levelShift[l])) * pallocSumBytes
	}
	totalSize = alignUp(totalSize, physPageSize)

	// Reserve memory for all levels in one go. There shouldn't be much for 32-bit.
	reservation := sysReserve(nil, totalSize)
	if reservation == nil {
		throw("failed to reserve page summary memory")
	}

	// Call miniterrno so that we can safely make system calls
	// before calling minit on m0.
	asmcgocall(unsafe.Pointer(abi.FuncPCABI0(miniterrno)), unsafe.Pointer(&libc____errno))

	ncpu = getncpu()
	if physPageSize == 0 {
		physPageSize = getPageSize()
	}
}

func tstart_sysvicall(newm *m) uint32

// May run with m.p==nil, so write barriers are not allowed.
//
//go:nowritebarrier
func newosproc(mp *m) {
	var (

				throw("mem: uninitialised memory")
			}
		}
	}
}

func memRound(p uintptr) uintptr {
	return alignUp(p, physPageSize)
}

func initBloc() {
	bloc = memRound(firstmoduledata.end)
	blocMax = bloc
}

func sysAllocOS(n uintptr) unsafe.Pointer {
	lock(&memlock)
	p := memAlloc(n)
	memCheck()

			return
		}
		var n uintptr
		for n = 4 << 10; n < size; n <<= 1 {
			err := mincore(unsafe.Pointer(uintptr(p)+n), 1, &addrspace_vec[0])
			if err == 0 {
				physPageSize = n
				break
			}
		}
		if physPageSize == 0 {
			physPageSize = size
		}
		munmap(p, size)
		return
	}

	n = read(fd, noescape(unsafe.Pointer(&auxvreadbuf[0])), int32(unsafe.Sizeof(auxvreadbuf)))
	closefd(fd)
	if n < 0 {

	if GOOS == "openbsd" && testing.Short() {
		t.Skip("skipping because virtual memory is limited; see #36210")
	}
	type test struct {
		request, expect uintptr
	}
	minPages := PhysPageSize / PageSize
	if minPages < 1 {
		minPages = 1
	}
	type setup struct {
		beforeAlloc map[ChunkIdx][]BitRange
		beforeScav  map[ChunkIdx][]BitRange
		expect      []test

	if hint.down {
		start, end = addr-heapArenaBytes, addr
		addr -= physPageSize
	} else {
		start, end = addr, addr+heapArenaBytes
	}
	got := sysReserve(unsafe.Pointer(addr), physPageSize)
	ok = (addr == uintptr(got))
	if !ok {
		// We were unable to get the requested reservation.
		// Release what we did get and fail.
		sysFreeOS(got, physPageSize)
	}
	return
}

func GetNextArenaHint() uintptr {

		throw("sem_post")
	}
}

func osinit() {
	// Call miniterrno so that we can safely make system calls
	// before calling minit on m0.
	miniterrno()

	ncpu = int32(sysconf(__SC_NPROCESSORS_ONLN))
	physPageSize = sysconf(__SC_PAGE_SIZE)
}

// newosproc0 is a version of newosproc that can be called before the runtime
// is initialized.
//