From: Yanfei Xu <[email protected]> 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.
BTW, drop an unnecessary cond_resched(), because there is a another cond_resched() followed it and no consumed invocation between them. Signed-off-by: Yanfei Xu <[email protected]> --- mm/khugepaged.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 2efe1d0c92ed..c293ec4a94ea 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_mmap_lock; if (likely(!khugepaged_test_exit(mm))) vma = find_vma(mm, khugepaged_scan.address); @@ -2101,7 +2103,6 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, for (; vma; vma = vma->vm_next) { unsigned long hstart, hend; - cond_resched(); if (unlikely(khugepaged_test_exit(mm))) { progress++; break; -- 2.27.0
