Merge "mm/ksm: Remove reuse_ksm_page()" (96bb1956) · Commits · e / devices / android_kernel_fairphone_FP5

include/linux/ksm.h

+0 −7

Original line number	Diff line number	Diff line
		@@ -53,8 +53,6 @@ struct page ksm_might_need_to_copy(struct page page,

		void rmap_walk_ksm(struct page page, struct rmap_walk_control rwc);
		void ksm_migrate_page(struct page newpage, struct page oldpage);
		bool reuse_ksm_page(struct page *page,
		struct vm_area_struct *vma, unsigned long address);

		#else /* !CONFIG_KSM */

		@@ -88,11 +86,6 @@ static inline void rmap_walk_ksm(struct page *page,
		static inline void ksm_migrate_page(struct page newpage, struct page oldpage)
		{
		}
		static inline bool reuse_ksm_page(struct page *page,
		struct vm_area_struct *vma, unsigned long address)
		{
		return false;
		}
		#endif /* CONFIG_MMU */
		#endif /* !CONFIG_KSM */

mm/ksm.c

+0 −25

Original line number	Diff line number	Diff line
		@@ -2660,31 +2660,6 @@ void rmap_walk_ksm(struct page page, struct rmap_walk_control rwc)
		goto again;
		}

		bool reuse_ksm_page(struct page *page,
		struct vm_area_struct *vma,
		unsigned long address)
		{
		#ifdef CONFIG_DEBUG_VM
		if (WARN_ON(is_zero_pfn(page_to_pfn(page))) \|\|
		WARN_ON(!page_mapped(page)) \|\|
		WARN_ON(!PageLocked(page))) {
		dump_page(page, "reuse_ksm_page");
		return false;
		}
		#endif

		if (PageSwapCache(page) \|\| !page_stable_node(page))
		return false;
		/* Prohibit parallel get_ksm_page() */
		if (!page_ref_freeze(page, 1))
		return false;

		page_move_anon_rmap(page, vma);
		page->index = linear_page_index(vma, address);
		page_ref_unfreeze(page, 1);

		return true;
		}
		#ifdef CONFIG_MIGRATION
		void ksm_migrate_page(struct page newpage, struct page oldpage)
		{

mm/memory.c

+17 −44

Original line number	Diff line number	Diff line
		@@ -2755,52 +2755,25 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf)
		* not dirty accountable.
		*/
		if (PageAnon(vmf->page)) {
		int total_map_swapcount;
		if (PageKsm(vmf->page) && (PageSwapCache(vmf->page) \|\|
		page_count(vmf->page) != 1))
		struct page *page = vmf->page;

		/* PageKsm() doesn't necessarily raise the page refcount */
		if (PageKsm(page) \|\| page_count(page) != 1)
		goto copy;
		if (!trylock_page(vmf->page)) {
		get_page(vmf->page);
		pte_unmap_unlock(vmf->pte, vmf->ptl);
		lock_page(vmf->page);
		if (!pte_map_lock(vmf)) {
		unlock_page(vmf->page);
		put_page(vmf->page);
		return VM_FAULT_RETRY;
		}
		if (!pte_same(*vmf->pte, vmf->orig_pte)) {
		unlock_page(vmf->page);
		pte_unmap_unlock(vmf->pte, vmf->ptl);
		put_page(vmf->page);
		return 0;
		}
		put_page(vmf->page);
		}
		if (PageKsm(vmf->page)) {
		bool reused = reuse_ksm_page(vmf->page, vmf->vma,
		vmf->address);
		unlock_page(vmf->page);
		if (!reused)
		if (!trylock_page(page))
		goto copy;
		if (PageKsm(page) \|\| page_mapcount(page) != 1 \|\| page_count(page) != 1) {
		unlock_page(page);
		goto copy;
		wp_page_reuse(vmf);
		return VM_FAULT_WRITE;
		}
		if (reuse_swap_page(vmf->page, &total_map_swapcount)) {
		if (total_map_swapcount == 1) {
		/*
		* The page is all ours. Move it to
		* our anon_vma so the rmap code will
		* not search our parent or siblings.
		* Protected against the rmap code by
		* the page lock.
		* Ok, we've got the only map reference, and the only
		* page count reference, and the page is locked,
		* it's dark out, and we're wearing sunglasses. Hit it.
		*/
		page_move_anon_rmap(vmf->page, vma);
		}
		unlock_page(vmf->page);
		wp_page_reuse(vmf);
		unlock_page(page);
		return VM_FAULT_WRITE;
		}
		unlock_page(vmf->page);
		} else if (unlikely((vmf->vma_flags & (VM_WRITE\|VM_SHARED)) ==
		(VM_WRITE\|VM_SHARED))) {
		return wp_page_shared(vmf);