diff options
Diffstat (limited to 'mm/memory.c')
-rw-r--r-- | mm/memory.c | 97 |
1 files changed, 42 insertions, 55 deletions
diff --git a/mm/memory.c b/mm/memory.c index 602f4283122f..469af373ae76 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -73,6 +73,7 @@ #include <linux/numa.h> #include <linux/perf_event.h> #include <linux/ptrace.h> +#include <linux/vmalloc.h> #include <trace/events/kmem.h> @@ -83,6 +84,7 @@ #include <asm/tlb.h> #include <asm/tlbflush.h> +#include "pgalloc-track.h" #include "internal.h" #if defined(LAST_CPUPID_NOT_IN_PAGE_FLAGS) && !defined(CONFIG_COMPILE_TEST) @@ -2206,7 +2208,8 @@ EXPORT_SYMBOL(vm_iomap_memory); static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, unsigned long addr, unsigned long end, - pte_fn_t fn, void *data, bool create) + pte_fn_t fn, void *data, bool create, + pgtbl_mod_mask *mask) { pte_t *pte; int err = 0; @@ -2214,7 +2217,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, if (create) { pte = (mm == &init_mm) ? - pte_alloc_kernel(pmd, addr) : + pte_alloc_kernel_track(pmd, addr, mask) : pte_alloc_map_lock(mm, pmd, addr, &ptl); if (!pte) return -ENOMEM; @@ -2235,6 +2238,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, break; } } while (addr += PAGE_SIZE, addr != end); + *mask |= PGTBL_PTE_MODIFIED; arch_leave_lazy_mmu_mode(); @@ -2245,7 +2249,8 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud, unsigned long addr, unsigned long end, - pte_fn_t fn, void *data, bool create) + pte_fn_t fn, void *data, bool create, + pgtbl_mod_mask *mask) { pmd_t *pmd; unsigned long next; @@ -2254,7 +2259,7 @@ static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud, BUG_ON(pud_huge(*pud)); if (create) { - pmd = pmd_alloc(mm, pud, addr); + pmd = pmd_alloc_track(mm, pud, addr, mask); if (!pmd) return -ENOMEM; } else { @@ -2264,7 +2269,7 @@ static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud, next = pmd_addr_end(addr, end); if (create || !pmd_none_or_clear_bad(pmd)) { err = apply_to_pte_range(mm, pmd, addr, next, fn, data, - create); + create, mask); if (err) break; } @@ -2274,14 +2279,15 @@ static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud, static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d, unsigned long addr, unsigned long end, - pte_fn_t fn, void *data, bool create) + pte_fn_t fn, void *data, bool create, + pgtbl_mod_mask *mask) { pud_t *pud; unsigned long next; int err = 0; if (create) { - pud = pud_alloc(mm, p4d, addr); + pud = pud_alloc_track(mm, p4d, addr, mask); if (!pud) return -ENOMEM; } else { @@ -2291,7 +2297,7 @@ static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d, next = pud_addr_end(addr, end); if (create || !pud_none_or_clear_bad(pud)) { err = apply_to_pmd_range(mm, pud, addr, next, fn, data, - create); + create, mask); if (err) break; } @@ -2301,14 +2307,15 @@ static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d, static int apply_to_p4d_range(struct mm_struct *mm, pgd_t *pgd, unsigned long addr, unsigned long end, - pte_fn_t fn, void *data, bool create) + pte_fn_t fn, void *data, bool create, + pgtbl_mod_mask *mask) { p4d_t *p4d; unsigned long next; int err = 0; if (create) { - p4d = p4d_alloc(mm, pgd, addr); + p4d = p4d_alloc_track(mm, pgd, addr, mask); if (!p4d) return -ENOMEM; } else { @@ -2318,7 +2325,7 @@ static int apply_to_p4d_range(struct mm_struct *mm, pgd_t *pgd, next = p4d_addr_end(addr, end); if (create || !p4d_none_or_clear_bad(p4d)) { err = apply_to_pud_range(mm, p4d, addr, next, fn, data, - create); + create, mask); if (err) break; } @@ -2331,8 +2338,9 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr, void *data, bool create) { pgd_t *pgd; - unsigned long next; + unsigned long start = addr, next; unsigned long end = addr + size; + pgtbl_mod_mask mask = 0; int err = 0; if (WARN_ON(addr >= end)) @@ -2343,11 +2351,14 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr, next = pgd_addr_end(addr, end); if (!create && pgd_none_or_clear_bad(pgd)) continue; - err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create); + err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create, &mask); if (err) break; } while (pgd++, addr = next, addr != end); + if (mask & ARCH_PAGE_TABLE_SYNC_MASK) + arch_sync_kernel_mappings(start, start + size); + return err; } @@ -2622,6 +2633,7 @@ static inline void wp_page_reuse(struct vm_fault *vmf) if (ptep_set_access_flags(vma, vmf->address, vmf->pte, entry, 1)) update_mmu_cache(vma, vmf->address, vmf->pte); pte_unmap_unlock(vmf->pte, vmf->ptl); + count_vm_event(PGREUSE); } /* @@ -2927,50 +2939,25 @@ 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(page)) + goto copy; + if (PageKsm(page) || page_mapcount(page) != 1 || page_count(page) != 1) { + unlock_page(page); goto copy; - if (!trylock_page(vmf->page)) { - get_page(vmf->page); - pte_unmap_unlock(vmf->pte, vmf->ptl); - lock_page(vmf->page); - vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, - vmf->address, &vmf->ptl); - if (!pte_same(*vmf->pte, vmf->orig_pte)) { - update_mmu_tlb(vma, vmf->address, vmf->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) - 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. - */ - page_move_anon_rmap(vmf->page, vma); - } - unlock_page(vmf->page); - wp_page_reuse(vmf); - return VM_FAULT_WRITE; } - unlock_page(vmf->page); + /* + * 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. + */ + wp_page_reuse(vmf); + unlock_page(page); + return VM_FAULT_WRITE; } else if (unlikely((vma->vm_flags & (VM_WRITE|VM_SHARED)) == (VM_WRITE|VM_SHARED))) { return wp_page_shared(vmf); |