On 12/1/21 15:30, Liam Howlett wrote:
> From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
>
> do_brk_munmap() has already aligned the address and has a maple tree
> state to be used. Use the new do_mas_align_munmap() to avoid
> unnecessary alignment and error checks.
>
> Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
> ---
> mm/mmap.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 14190306a483..79b8494d83c6 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -2926,12 +2926,15 @@ static int do_brk_munmap(struct ma_state *mas, struct vm_area_struct *vma,
> struct mm_struct *mm = vma->vm_mm;
> struct vm_area_struct unmap;
> unsigned long unmap_pages;
> - int ret = 1;
> + int ret;
>
> arch_unmap(mm, newbrk, oldbrk);
>
> - if (likely(vma->vm_start >= newbrk)) { // remove entire mapping(s)
> - ret = do_mas_munmap(mas, mm, newbrk, oldbrk-newbrk, uf, true);
> + if (likely((vma->vm_end < oldbrk) ||
> + ((vma->vm_start == newbrk) && (vma->vm_end == oldbrk)))) {
Can you describe this change of conditions in the commit log as well?
> + // remove entire mapping(s)
> + ret = do_mas_align_munmap(mas, vma, mm, newbrk, oldbrk, uf,
> + true);
> goto munmap_full_vma;
> }
>
