On 12/1/21 15:29, Liam Howlett wrote:
> From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
>
> Remove the RB tree and start using the maple tree for vm_area_struct
> tracking.
>
> Drop validate_mm() calls in expand_upwards() and expand_downwards() as
> the lock is not held.
>
> Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
> ---
> arch/x86/kernel/tboot.c | 1 -
> drivers/firmware/efi/efi.c | 1 -
> include/linux/mm.h | 2 -
> include/linux/mm_types.h | 14 --
> kernel/fork.c | 8 -
> mm/init-mm.c | 2 -
> mm/mmap.c | 496 ++++++++-----------------------------
> mm/nommu.c | 88 ++-----
> mm/util.c | 8 +
> 9 files changed, 136 insertions(+), 484 deletions(-)
Nice stats.
Wanted to suggest splitting out the swith to range_has_overlap() but I think
I see how it's not feasible.
> diff --git a/mm/util.c b/mm/util.c
> index e58151a61255..ab02382c2d57 100644
> --- a/mm/util.c
> +++ b/mm/util.c
> @@ -287,6 +287,8 @@ void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
> vma->vm_next = next;
> if (next)
> next->vm_prev = vma;
> + else
> + mm->highest_vm_end = vm_end_gap(vma);
> }
>
> void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma)
> @@ -301,6 +303,12 @@ void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma)
> mm->mmap = next;
> if (next)
> next->vm_prev = prev;
> + else {
Nit: style suggests that once else is { } block then if block should be too,
even though it remains a single line.
> + if (prev)
> + mm->highest_vm_end = vm_end_gap(prev);
> + else
> + mm->highest_vm_end = 0;
> + }
> }
>
> /* Check if the vma is being used as a stack by this task */
