}

// pages64 returns a 64-bit bitmap representing a block of 64 pages aligned
// to 64 pages. The returned block of pages is the one containing the i'th
// page in this pallocBits. Each bit represents whether the page is in-use.
func (b *pallocBits) pages64(i uint) uint64 {
	return (*pageBits)(b).block64(i)
}

// allocPages64 allocates a 64-bit block of 64 pages aligned to 64 pages according

// directio.AlignSize is defined as 0 in MacOS causing divide by 0 error.
const DirectioAlignSize = 4096

// CopyAligned - copies from reader to writer using the aligned input
// buffer, it is expected that input buffer is page aligned to
// 4K page boundaries. Without passing aligned buffer may cause
// this function to return error.
//
// This code is similar in spirit to io.Copy but it is only to be

	m.mutex.Lock()
	defer m.mutex.Unlock()
	for resource, requested := range accumulatedResourceRequests {
		// Only consider devices that actually contain topology information.
		if aligned := m.deviceHasTopologyAlignment(resource); !aligned {
			klog.InfoS("Resource does not have a topology preference", "resource", resource)
			deviceHints[resource] = nil
			continue
		}

	// nothing else allocates from it.
	runtime.Acquirem()

	// Make 1-byte allocations until we get a fresh tiny slot.
	aligned := false
	for i := 0; i < 16; i++ {
		x := runtime.Escape(new(byte))
		if uintptr(unsafe.Pointer(x))&0xf == 0xf {
			aligned = true
			break
		}
	}
	if !aligned {
		runtime.Releasem()
		t.Fatal("unable to get a fresh tiny slot")
	}

	// Create a 4-byte object so that the current

	alignedCPUs := cpuset.New()
	numaBits := numaAffinity.GetBits()

	// If align-by-socket policy option is enabled, NUMA based hint is expanded to
	// socket aligned hint. It will ensure that first socket aligned available CPUs are
	// allocated before we try to find CPUs across socket to satisfy allocation request.
	if p.options.AlignBySocket {

// Lock is a no-op used by -copylocks checker from `go vet`.
func (*noCopy) Lock()   {}
func (*noCopy) Unlock() {}

// align64 may be added to structs that must be 64-bit aligned.
// This struct is recognized by a special case in the compiler
// and will not work if copied to any other package.

		if err != nil {
			return nil, err
		}
		if allocateRemainingFrom(preferred.Intersection(aligned)) {
			return allocated, nil
		}
		// Then fallback to allocate from the aligned set if no preferred list
		// is returned (or not enough devices are returned in that list).
		if allocateRemainingFrom(aligned) {
			return allocated, nil
		}

how to handle OVG information, and much more.

5. Align directive

Starting with Go 1.12, Go asm supports the PCALIGN directive, which indicates
that the next instruction should be aligned to the specified value. Currently
8 and 16 are the only supported values, and a maximum of 2 NOPs will be added
to align the code. That means in the case where the code is aligned to 4 but

func (s *mspan) refreshPinnerBits() {
	p := s.getPinnerBits()
	if p == nil {
		return
	}

	hasPins := false
	bytes := alignUp(s.pinnerBitSize(), 8)

	// Iterate over each 8-byte chunk and check for pins. Note that
	// newPinnerBits guarantees that pinnerBits will be 8-byte aligned, so we
	// don't have to worry about edge cases, irrelevant bits will simply be
	// zero.

//
// *ptr is uninitialized memory (e.g., memory that's being reused
// for a new allocation) and hence contains only "junk".
//
// memclrNoHeapPointers ensures that if ptr is pointer-aligned, and n
// is a multiple of the pointer size, then any pointer-aligned,
// pointer-sized portion is cleared atomically. Despite the function
// name, this is necessary because this function is the underlying