Re: [PATCH 9/9] mm/madvise: remove !tlb support from madvise_{dontneed,free}_single_vma()

[SeongJae Park]

On Wed, 12 Mar 2025 13:46:38 +0000 Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> wrote:

> On Tue, Mar 11, 2025 at 02:02:11PM -0700, SeongJae Park wrote:
> > On Tue, 11 Mar 2025 14:01:20 +0000 Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> wrote:
> >
> > > On Mon, Mar 10, 2025 at 10:23:18AM -0700, SeongJae Park wrote:
> > > > madvise_dontneed_single_vma() and madvise_free_single_vma() support both
> > > > batched tlb flushes and unbatched tlb flushes use cases depending on
> > > > received tlb parameter's value.  The supports were for safe and fine
> > > > transition of the usages from the unbatched flushes to the batched ones.
> > > > Now the transition is done, and therefore there is no real unbatched tlb
> > > > flushes use case.  Remove the code for supporting the no more being used
> > > > cases.
> > > >
> > > > Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
> > >
> > > Obviously I support this based on previous preview :) but I wonder if we
> > > can avoid this horrid caller_tlb pattern in the first instance.
> >
> > I will try, though I have no good idea for that for now.
> >
> > Maybe we could simply squash patches 7-9.  I'm bit concerned if it makes
> > changes unnecessariy mixed and not small, but I have no strong opinion about
> > it.  Please feel free to let me know if you want that.
> 
> Yeah, though maybe try to make things as incremental as possible within
> that?

Now I think we can make entire batching change for MADV_FREE first, and then
make another change for MADV_DONTNEED[_LOCKED].  In the way, the caller_tlb
pattern will not be introduced at all and changes in individual commit would be
small and dense.

Please let me know if you have any concern about it.  If I don't hear some
concerns about it, I will format the next spin in the way.


Thanks,
SJ

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