Commit 7ee07a44 authored by Jianyu Zhan's avatar Jianyu Zhan Committed by Linus Torvalds
Browse files

mm: fold mlocked_vma_newpage() into its only call site 



In previous commit(mm: use the light version __mod_zone_page_state in
mlocked_vma_newpage()) a irq-unsafe __mod_zone_page_state is used.  And as
suggested by Andrew, to reduce the risks that new call sites incorrectly
using mlocked_vma_newpage() without knowing they are adding racing, this
patch folds mlocked_vma_newpage() into its only call site,
page_add_new_anon_rmap, to make it open-cocded for people to know what is
going on.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: default avatarJianyu Zhan <nasa4836@gmail.com>
Suggested-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Suggested-by: default avatarHugh Dickins <hughd@google.com>
Acked-by: default avatarHugh Dickins <hughd@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent bea04b07

mm/internal.h

+0 −29
Original line number Diff line number Diff line
@@ -188,31 +188,6 @@ static inline void munlock_vma_pages_all(struct vm_area_struct *vma) 
	munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);

}



/*

 * Called only in fault path, to determine if a new page is being

 * mapped into a LOCKED vma.  If it is, mark page as mlocked.

 */

static inline int mlocked_vma_newpage(struct vm_area_struct *vma,

				    struct page *page)

{

	VM_BUG_ON_PAGE(PageLRU(page), page);



	if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))

		return 0;



	if (!TestSetPageMlocked(page)) {

		/*

		 * We use the irq-unsafe __mod_zone_page_stat because this

		 * counter is not modified from interrupt context, and the pte

		 * lock is held(spinlock), which implies preemption disabled.

		 */

		__mod_zone_page_state(page_zone(page), NR_MLOCK,

				    hpage_nr_pages(page));

		count_vm_event(UNEVICTABLE_PGMLOCKED);

	}

	return 1;

}



/*

 * must be called with vma's mmap_sem held for read or write, and page locked.

 */
@@ -255,10 +230,6 @@ extern unsigned long vma_address(struct page *page, 
				 struct vm_area_struct *vma);

#endif

#else /* !CONFIG_MMU */

static inline int mlocked_vma_newpage(struct vm_area_struct *v, struct page *p)

{

	return 0;

}

static inline void clear_page_mlock(struct page *page) { }

static inline void mlock_vma_page(struct page *page) { }

static inline void mlock_migrate_page(struct page *new, struct page *old) { }

mm/rmap.c

+17 −3
Original line number Diff line number Diff line
@@ -1032,10 +1032,24 @@ void page_add_new_anon_rmap(struct page *page, 
	__mod_zone_page_state(page_zone(page), NR_ANON_PAGES,

			hpage_nr_pages(page));

	__page_set_anon_rmap(page, vma, address, 1);

	if (!mlocked_vma_newpage(vma, page)) {



	VM_BUG_ON_PAGE(PageLRU(page), page);

	if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) {

		SetPageActive(page);

		lru_cache_add(page);

	} else

		return;

	}



	if (!TestSetPageMlocked(page)) {

		/*

		 * We use the irq-unsafe __mod_zone_page_stat because this

		 * counter is not modified from interrupt context, and the pte

		 * lock is held(spinlock), which implies preemption disabled.

		 */

		__mod_zone_page_state(page_zone(page), NR_MLOCK,

				    hpage_nr_pages(page));

		count_vm_event(UNEVICTABLE_PGMLOCKED);

	}

	add_page_to_unevictable_list(page);

}

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