On Wed, 2014-02-26 at 09:40 +1100, Benjamin Herrenschmidt wrote:

On Tue, 2014-02-25 at 13:29 +0530, Deepthi Dharwar wrote:

quoted

We currently do not use smt-snooze-delay in the kernel.
The sysfs entries needs to  be retained until we do a clean up
ppc64_cpu
util that uses these entries to determine SMT,
clean up patch for this has already been posted out by Prerna.
Once, we have the ppc64_cpu changes in, we can look to clean up these
parts from the kernel.

We generally shouldn't change user visible interfaces.

People still have old versions of ppc64_cpu, we must not break them

Yeah we can't remove the file entirely, at least for a few more years.

ppc64_cpu should never have used that file to determine if a cpu existed, but
it did, so we're stuck with it.

What we can do is remove the unused percpu, and just leave the file in sysfs,
and have it print a warning when anyone touches it.

cheers