Hello

  
static inline unsigned int generic_hweight32(unsigned int w)
{
    unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
    res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
    res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
    res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
    return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
}

static inline unsigned int generic_hweight16(unsigned int w)
{
    unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
    res = (res & 0x3333) + ((res >> 2) & 0x3333);
    res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
    return (res & 0x00FF) + ((res >> 8) & 0x00FF);
}

static inline unsigned int generic_hweight8(unsigned int w)
{
    unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
    res = (res & 0x33) + ((res >> 2) & 0x33);
    return (res & 0x0F) + ((res >> 4) & 0x0F);
}

static inline unsigned long generic_hweight64(__u64 w)
{
#if BITS_PER_LONG < 64
    return generic_hweight32((unsigned int)(w >> 32)) +
        generic_hweight32((unsigned int)w);
#else
    u64 res;
    res = (w & 0x5555555555555555ul) + ((w >> 1) & 0x5555555555555555ul);
    res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul);
    res = (res & 0x0F0F0F0F0F0F0F0Ful) + ((res >> 4) & 0x0F0F0F0F0F0F0F0Ful);
    res = (res & 0x00FF00FF00FF00FFul) + ((res >> 8) & 0x00FF00FF00FF00FFul);
    res = (res & 0x0000FFFF0000FFFFul) + ((res >> 16) & 0x0000FFFF0000FFFFul);
    return (res & 0x00000000FFFFFFFFul) + ((res >> 32) & 0x00000000FFFFFFFFul);
#endif
}