Re: [PATCH] tools/perf: fix the word selected in find_*_bit

[George Spelvin]

Madhavan Srinivasan wrote:
> +#if (__BYTE_ORDER == __BIG_ENDIAN) && (BITS_PER_LONG != 64)
> +	tmp = addr[(((nbits - 1)/BITS_PER_LONG) - (start / BITS_PER_LONG))]
> +								^ invert;
> +#else
>  	tmp = addr[start / BITS_PER_LONG] ^ invert;
> +#endif

Than you for diagnosing this problem, but I don't think the fix
is correct.

1) It's not clear that all users of _find_next_bit and for_each_set_bit()
   want this change.
2) Is your code even correct?  I'd think you'd want addr[x ^ 1].  Are you
   sure you shpuld be reversing the whole array, and not just the halves of
   each 64-bit word?
3) You've now broken the case of 32-bit big-endian kernel.

I think the proper solution is uglier than this. :-(