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Both callers walk a VMA a table at > a time, so let them work it out once and pass the mask in. It is only > good while the lock that produced it is held, so madvise_collapse() takes > it again after every collapse. > > The mask is then sampled once per VMA rather than once per table. A thp > enabled knob written during a walk takes effect one VMA later, and cannot > widen a collapse: hugepage_vma_revalidate() tests the order again under > the lock the collapse retakes. > > Assisted-by: LLM > Signed-off-by: Kiryl Shutsemau (Meta) > --- > mm/khugepaged.c | 32 ++++++++++++++++++-------------- > 1 file changed, 18 insertions(+), 14 deletions(-) > LGTM. Reviewed-by: Zi Yan --=20 Best Regards, Yan, Zi