From: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> Subject: mm/mmap.c: extract __vma_unlink_list() as counterpart for __vma_link_list() Just make the code a little easier to read. Link: http://lkml.kernel.org/r/20191006012636.31521-3-richardw.yang@xxxxxxxxxxxxxxx Signed-off-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/internal.h | 1 + mm/mmap.c | 12 +----------- mm/nommu.c | 8 +------- mm/util.c | 14 ++++++++++++++ 4 files changed, 17 insertions(+), 18 deletions(-) --- a/mm/internal.h~mm-mmapc-extract-__vma_unlink_list-as-counter-part-for-__vma_link_list +++ a/mm/internal.h @@ -291,6 +291,7 @@ static inline bool is_data_mapping(vm_fl /* mm/util.c */ void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, struct rb_node *rb_parent); +void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma); #ifdef CONFIG_MMU extern long populate_vma_page_range(struct vm_area_struct *vma, --- a/mm/mmap.c~mm-mmapc-extract-__vma_unlink_list-as-counter-part-for-__vma_link_list +++ a/mm/mmap.c @@ -686,18 +686,8 @@ static __always_inline void __vma_unlink struct vm_area_struct *vma, struct vm_area_struct *ignore) { - struct vm_area_struct *prev, *next; - vma_rb_erase_ignore(vma, &mm->mm_rb, ignore); - next = vma->vm_next; - prev = vma->vm_prev; - if (prev) - prev->vm_next = next; - else - mm->mmap = next; - if (next) - next->vm_prev = prev; - + __vma_unlink_list(mm, vma); /* Kill the cache */ vmacache_invalidate(mm); } --- a/mm/nommu.c~mm-mmapc-extract-__vma_unlink_list-as-counter-part-for-__vma_link_list +++ a/mm/nommu.c @@ -684,13 +684,7 @@ static void delete_vma_from_mm(struct vm /* remove from the MM's tree and list */ rb_erase(&vma->vm_rb, &mm->mm_rb); - if (vma->vm_prev) - vma->vm_prev->vm_next = vma->vm_next; - else - mm->mmap = vma->vm_next; - - if (vma->vm_next) - vma->vm_next->vm_prev = vma->vm_prev; + __vma_unlink_list(mm, vma); } /* --- a/mm/util.c~mm-mmapc-extract-__vma_unlink_list-as-counter-part-for-__vma_link_list +++ a/mm/util.c @@ -292,6 +292,20 @@ void __vma_link_list(struct mm_struct *m next->vm_prev = vma; } +void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma) +{ + struct vm_area_struct *prev, *next; + + next = vma->vm_next; + prev = vma->vm_prev; + if (prev) + prev->vm_next = next; + else + mm->mmap = next; + if (next) + next->vm_prev = prev; +} + /* Check if the vma is being used as a stack by this task */ int vma_is_stack_for_current(struct vm_area_struct *vma) { _