On Tue, Apr 6, 2021 at 8:06 PM <yanfei.xu@xxxxxxxxxxxxx> wrote: > > From: Yanfei Xu <yanfei.xu@xxxxxxxxxxxxx> > > We could check MMF_DISABLE_THP ahead of iterating over all of vma. > Otherwise if some mm_struct contain a large number of vma, there will > be amounts meaningless cpu cycles cost. Reviewed-by: Yang Shi <shy828301@xxxxxxxxx> > > Signed-off-by: Yanfei Xu <yanfei.xu@xxxxxxxxxxxxx> > --- > mm/khugepaged.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index a6012b9259a2..f4ad25a7db55 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -2094,6 +2094,8 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, > */ > if (unlikely(!mmap_read_trylock(mm))) > goto breakouterloop_mmap_lock; > + if (test_bit(MMF_DISABLE_THP, &mm->flags)) > + goto breakouterloop; > if (likely(!khugepaged_test_exit(mm))) > vma = find_vma(mm, khugepaged_scan.address); > > -- > 2.27.0 >
