[stable 9] broken hwpstate calls

[Andriy Gapon]

on 31/05/2012 23:28 Jung-uk Kim said the following:
> It is simple but I don't like locking scheduler, binding CPU, and writing
> the same MSR, multiple times for each core.

Not sure if parse this.  The MSR is _written_ /once/ for each core.
(BTW, "locking scheduler" is not a completely accurate description of what
thread_lock does)

> Besides, it introduces more delay and you may be reading the correct
> status because of that. :-P

Having a separate reading pass does introduce more delay indeed.
Reading the correct status is a good thing, OTOH.  Why would anyone want to
read incorrect status?  (just want to note that "correct" and "expected" are
different things)

> If people really think checking MSRC001_0071[18:16] is unworthy for

Well, "other people" hasn't demonstrated/proved/convinced yet that it is worthy

> Bulldozer, I prefer skipping status check

That's what I suggested from the very start.

> but I disagree with this patch.

Since I am not invested in this issue (I am not affected by the problem and I
do not have any personal attachment to the code in question), I will just
defer any decision to those who do care about the problem.  I hope that a fix
will be provided in the end.

-- 
Andriy Gapon