Re: [PATCH v3 0/6] powerpc: queued spinlocks and rwlocks

Peter Zijlstra
2020-07-09T08:31:13Z

On Wed, Jul 08, 2020 at 07:54:34PM -0400, Waiman Long wrote:
> On 7/8/20 4:41 AM, Peter Zijlstra wrote:
> > On Tue, Jul 07, 2020 at 03:57:06PM +1000, Nicholas Piggin wrote:
> > > Yes, powerpc could certainly get more performance out of the slow
> > > paths, and then there are a few parameters to tune.
> > Can you clarify? The slow path is already in use on ARM64 which is weak,
> > so I doubt there's superfluous serialization present. And Will spend a
> > fair amount of time on making that thing guarantee forward progressm, so
> > there just isn't too much room to play.
> >
> > > We don't have a good alternate patching for function calls yet, but
> > > that would be something to do for native vs pv.
> > Going by your jump_label implementation, support for static_call should
> > be fairly straight forward too, no?
> >
> > https://lkml.kernel.org/r/20200624153024.794671356@infradead.org
> >
> Speaking of static_call, I am also looking forward to it. Do you have an
> idea when that will be merged?

0day had one crash on the last round, I think Steve send a fix for that
last night and I'll go look at it.

That said, the last posting got 0 feedback, so either everybody is
really happy with it, or not interested. So let us know in the thread,
with some review feedback.

Once I get through enough of the inbox to actually find the fix and test
it, I'll also update the thread, and maybe threaten to merge it if
everybody stays silent :-)