On Thu, Feb 15, 2024 at 10:32:01AM +0000, Ryan Roberts wrote: > Optimize the contpte implementation to fix some of the > exit/munmap/dontneed performance regression introduced by the initial > contpte commit. Subsequent patches will solve it entirely. > > During exit(), munmap() or madvise(MADV_DONTNEED), mappings must be > cleared. Previously this was done 1 PTE at a time. But the core-mm > supports batched clear via the new [get_and_]clear_full_ptes() APIs. So > let's implement those APIs and for fully covered contpte mappings, we no > longer need to unfold the contpte. This significantly reduces unfolding > operations, reducing the number of tlbis that must be issued. > > Tested-by: John Hubbard <jhubbard@xxxxxxxxxx> > Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
