Re: [PATCH 1/2] mm: mmap: no need to call khugepaged_enter_vma() for stack

From: Yin Fengwei
Date: Tue Jan 09 2024 - 20:36:15 EST




On 2023/12/21 14:59, Yang Shi wrote:
From: Yang Shi <yang@xxxxxxxxxxxxxxxxxxxxxx>

We avoid allocating THP for temporary stack, even tnough
khugepaged_enter_vma() is called for stack VMAs, it actualy returns
false. So no need to call it in the first place at all.

Signed-off-by: Yang Shi <yang@xxxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Yin Fengwei <fengwei.yin@xxxxxxxxx>

---
mm/mmap.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index b78e83d351d2..2ff79b1d1564 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2046,7 +2046,6 @@ static int expand_upwards(struct vm_area_struct *vma, unsigned long address)
}
}
anon_vma_unlock_write(vma->anon_vma);
- khugepaged_enter_vma(vma, vma->vm_flags);
mas_destroy(&mas);
validate_mm(mm);
return error;
@@ -2140,7 +2139,6 @@ int expand_downwards(struct vm_area_struct *vma, unsigned long address)
}
}
anon_vma_unlock_write(vma->anon_vma);
- khugepaged_enter_vma(vma, vma->vm_flags);
mas_destroy(&mas);
validate_mm(mm);
return error;