Excerpts from Andy Lutomirski's message of June 5, 2021 3:05 am:

On 6/4/21 9:54 AM, Andy Lutomirski wrote:

quoted

On 5/31/21 11:22 PM, Nicholas Piggin wrote:

quoted

There haven't been objections to the series since last posting, this
is just a rebase and tidies up a few comments minor patch rearranging.

I continue to object to having too many modes.  I like my more generic
improvements better.  Let me try to find some time to email again.

Specifically, this:

https://git.kernel.org/pub/scm/linux/kernel/git/luto/linux.git/commit/?h=x86/mm

That's worse than what powerpc does with the shoot lazies code so 
we wouldn't use it anyway.

The fact is mm-cpumask and lazy mm is very architecture specific, so I 
don't really see that another "mode" is such a problem, it's for the 
most part "this is what powerpc does" -> "this is what powerpc does".
The only mode in the context switch is just "take a ref on the lazy mm"
or "don't take a ref". Surely that's not too onerous to add!?

Actually the bigger part of it is actually the no-lazy mmu mode which
is not yet used, I thought it was a neat little demonstrator of how code
works with/without lazy but I will get rid of that for submission.

I, or someone, needs to dust off my membarrier series before any of
these kinds of changes get made.  The barrier situation in the scheduler
is too confusing otherwise.

I disagree, I've disentangled the changes from membarrier stuff now, 
they can be done concurrently.

Thanks,
Nick