Re: perf: more ABI breakage

[Vince Weaver]

On Mon, 8 Jul 2013, Peter Zijlstra wrote:

> Urgh, so the 3.9 patches should never have been merged and sunk in while I was
> doing my vegetable imitation.
> 
> Stephane agreed with the change in 3.10; and I suppose he overlooked the fact
> that people were already using it :/ I specifically asked if there were already
> users as that would indeed require some form of backwards compatibility --
> however annoying.

I probably was just hoping no one was using it, and since I don't own any 
fam15h hardware myself it didn't affect me directly.

The problem is that AMD NB support was so long in coming that everyone 
eagerly jumped on it when it arrived, to the extent of running -rc 3.9
kernels.

We can only hope that 3.9 is not chosen as long-term-stable, and that
RHEL and the HPC vendors don't decide to backport the 3.9 support to their 
older kernels.  If so we're stuck with it for a while :(

It looks like it will be possible for libpfm4/PAPI to sort of paper over 
this but it's going to be annoying :(

Vince
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/