Re: ftrace histogram sorting broken on BE architecures

Steven Rostedt
2019-12-16T18:29:27Z

On Mon, 16 Dec 2019 17:06:50 +0000
David Laight <David.Laight@ACULAB.COM> wrote:

> > Where original_val_a could be a byte, short, int, long or long long.
>
> I'd sort of guessed that, but then the pointer type passed to tracing_map_cmp_##type()
> will always be 'u64 *' (since the field the address is taken of must be that type).
> Then the (u64 *) casts are no longer needed.
>
> Possibly you can just pass the u64 values to:
> tracing_map_cmp_##type(type a, type b)
> {
> return a > b ? 1 : a < b ? -1 : 0;
> }
>
> The high bit masking and sign extension is then implicit in the call.

But these are used to pass into a compare function that takes compare
functions that are something other than numbers. They can be pointers
to strings.

-- Steve