Function StoreFBClockDataV2

fbclock/shmem_notlinux.go:241–251

StoreFBClockDataV2 writes the primary anchor section. The two sections are independent seqlock sections on separate cache lines, mirroring the C fbclock_shmdata_v2 layout, so each is written by its own call.

(fd uintptr, d DataV2)

// independent seqlock sections on separate cache lines, mirroring the C
// fbclock_shmdata_v2 layout, so each is written by its own call.
func StoreFBClockDataV2(fd uintptr, d DataV2) error {
	data, err := unix.Mmap(int(fd), 0, shmDataV2Size, unix.PROT_READ|unix.PROT_WRITE, unix.MAP_SHARED) //nolint:gosec
	if err != nil {
		return fmt.Errorf("mmap failed: %w", err)
	}
	defer func() { _ = unix.Munmap(data) }()

	return storeSeqlockSection(data, shmV2PrimarySeqOff, func(buf []byte) {
		writeClockDataV2(buf, d)
	})
}

// StoreFBClockDataRealtime writes the realtime anchor section, used on hosts
// whose primary is MONOTONIC_RAW. Separate call from StoreFBClockDataV2 so the