From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Davies Date: Thu, 13 Jul 2006 14:29:30 +1000 Message-Id: <20060713042930.9978.28392.sendpatchset@localhost.localdomain> In-Reply-To: <20060713042630.9978.66924.sendpatchset@localhost.localdomain> References: <20060713042630.9978.66924.sendpatchset@localhost.localdomain> Subject: [PATCH 17/18] PTI - Swapfile iterator abstraction Sender: owner-linux-mm@kvack.org Return-Path: To: linux-mm@kvack.org Cc: Paul Davies List-ID: Abstracts swapfile iterator from swapfile.c and puts it in pt_default.c Signed-Off-By: Paul Davies --- pt-default.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ swapfile.c | 77 ++------------------------------------------------------- 2 files changed, 83 insertions(+), 73 deletions(-) Index: linux-2.6.17.2/mm/swapfile.c =================================================================== --- linux-2.6.17.2.orig/mm/swapfile.c 2006-06-30 10:17:23.000000000 +1000 +++ linux-2.6.17.2/mm/swapfile.c 2006-07-08 22:00:07.309931488 +1000 @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -483,7 +484,7 @@ * just let do_wp_page work it out if a write is requested later - to * force COW, vm_page_prot omits write permission from any private vma. */ -static void unuse_pte(struct vm_area_struct *vma, pte_t *pte, +void unuse_pte(struct vm_area_struct *vma, pte_t *pte, unsigned long addr, swp_entry_t entry, struct page *page) { inc_mm_counter(vma->vm_mm, anon_rss); @@ -499,72 +500,10 @@ activate_page(page); } -static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long addr, unsigned long end, - swp_entry_t entry, struct page *page) -{ - pte_t swp_pte = swp_entry_to_pte(entry); - pte_t *pte; - spinlock_t *ptl; - int found = 0; - - pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); - do { - /* - * swapoff spends a _lot_ of time in this loop! - * Test inline before going to call unuse_pte. - */ - if (unlikely(pte_same(*pte, swp_pte))) { - unuse_pte(vma, pte++, addr, entry, page); - found = 1; - break; - } - } while (pte++, addr += PAGE_SIZE, addr != end); - pte_unmap_unlock(pte - 1, ptl); - return found; -} - -static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud, - unsigned long addr, unsigned long end, - swp_entry_t entry, struct page *page) -{ - pmd_t *pmd; - unsigned long next; - - pmd = pmd_offset(pud, addr); - do { - next = pmd_addr_end(addr, end); - if (pmd_none_or_clear_bad(pmd)) - continue; - if (unuse_pte_range(vma, pmd, addr, next, entry, page)) - return 1; - } while (pmd++, addr = next, addr != end); - return 0; -} - -static inline int unuse_pud_range(struct vm_area_struct *vma, pgd_t *pgd, - unsigned long addr, unsigned long end, - swp_entry_t entry, struct page *page) -{ - pud_t *pud; - unsigned long next; - - pud = pud_offset(pgd, addr); - do { - next = pud_addr_end(addr, end); - if (pud_none_or_clear_bad(pud)) - continue; - if (unuse_pmd_range(vma, pud, addr, next, entry, page)) - return 1; - } while (pud++, addr = next, addr != end); - return 0; -} - static int unuse_vma(struct vm_area_struct *vma, swp_entry_t entry, struct page *page) { - pgd_t *pgd; - unsigned long addr, end, next; + unsigned long addr, end; if (page->mapping) { addr = page_address_in_vma(page, vma); @@ -577,15 +516,7 @@ end = vma->vm_end; } - pgd = pgd_offset(vma->vm_mm, addr); - do { - next = pgd_addr_end(addr, end); - if (pgd_none_or_clear_bad(pgd)) - continue; - if (unuse_pud_range(vma, pgd, addr, next, entry, page)) - return 1; - } while (pgd++, addr = next, addr != end); - return 0; + return unuse_vma_read_iterator(vma, addr, end, entry, page); } static int unuse_mm(struct mm_struct *mm, Index: linux-2.6.17.2/mm/pt-default.c =================================================================== --- linux-2.6.17.2.orig/mm/pt-default.c 2006-07-08 21:53:14.552151216 +1000 +++ linux-2.6.17.2/mm/pt-default.c 2006-07-08 22:01:25.216087952 +1000 @@ -1042,3 +1042,82 @@ return len + old_addr - old_end; /* how much done */ } + +static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long end, + swp_entry_t entry, struct page *page) +{ + pte_t swp_pte = swp_entry_to_pte(entry); + pte_t *pte; + spinlock_t *ptl; + int found = 0; + + pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); + do { + /* + * swapoff spends a _lot_ of time in this loop! + * Test inline before going to call unuse_pte. + */ + if (unlikely(pte_same(*pte, swp_pte))) { + unuse_pte(vma, pte++, addr, entry, page); + found = 1; + break; + } + } while (pte++, addr += PAGE_SIZE, addr != end); + pte_unmap_unlock(pte - 1, ptl); + return found; +} + +static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud, + unsigned long addr, unsigned long end, + swp_entry_t entry, struct page *page) +{ + pmd_t *pmd; + unsigned long next; + + pmd = pmd_offset(pud, addr); + do { + next = pmd_addr_end(addr, end); + if (pmd_none_or_clear_bad(pmd)) + continue; + if (unuse_pte_range(vma, pmd, addr, next, entry, page)) + return 1; + } while (pmd++, addr = next, addr != end); + return 0; +} + +static inline int unuse_pud_range(struct vm_area_struct *vma, pgd_t *pgd, + unsigned long addr, unsigned long end, + swp_entry_t entry, struct page *page) +{ + pud_t *pud; + unsigned long next; + + pud = pud_offset(pgd, addr); + do { + next = pud_addr_end(addr, end); + if (pud_none_or_clear_bad(pud)) + continue; + if (unuse_pmd_range(vma, pud, addr, next, entry, page)) + return 1; + } while (pud++, addr = next, addr != end); + return 0; +} + +int unuse_vma_read_iterator(struct vm_area_struct *vma, + unsigned long addr, unsigned long end, swp_entry_t entry, + struct page *page) +{ + pgd_t *pgd; + unsigned long next; + + pgd = pgd_offset(vma->vm_mm, addr); + do { + next = pgd_addr_end(addr, end); + if (pgd_none_or_clear_bad(pgd)) + continue; + if (unuse_pud_range(vma, pgd, addr, next, entry, page)) + return 1; + } while (pgd++, addr = next, addr != end); + return 0; +} -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org