Commit 4c21e2f2 authored by Hugh Dickins's avatar Hugh Dickins Committed by Linus Torvalds

[PATCH] mm: split page table lock

Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.

This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock.  (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)

In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.

Splitting the lock is not quite for free: another cacheline access.  Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS.  But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.

There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent b38c6845
......@@ -229,6 +229,7 @@ void free_pgd_slow(pgd_t *pgd)
pte = pmd_page(*pmd);
pmd_clear(pmd);
dec_page_state(nr_page_table_pages);
pte_lock_deinit(pte);
pte_free(pte);
pmd_free(pmd);
free:
......
......@@ -87,14 +87,14 @@ static inline void pgd_list_add(pgd_t *pgd)
if (pgd_list)
pgd_list->private = (unsigned long) &page->index;
pgd_list = page;
page->private = (unsigned long) &pgd_list;
set_page_private(page, (unsigned long)&pgd_list);
}
static inline void pgd_list_del(pgd_t *pgd)
{
struct page *next, **pprev, *page = virt_to_page(pgd);
next = (struct page *) page->index;
pprev = (struct page **) page->private;
pprev = (struct page **)page_private(page);
*pprev = next;
if (next)
next->private = (unsigned long) pprev;
......
......@@ -188,19 +188,19 @@ static inline void pgd_list_add(pgd_t *pgd)
struct page *page = virt_to_page(pgd);
page->index = (unsigned long)pgd_list;
if (pgd_list)
pgd_list->private = (unsigned long)&page->index;
set_page_private(pgd_list, (unsigned long)&page->index);
pgd_list = page;
page->private = (unsigned long)&pgd_list;
set_page_private(page, (unsigned long)&pgd_list);
}
static inline void pgd_list_del(pgd_t *pgd)
{
struct page *next, **pprev, *page = virt_to_page(pgd);
next = (struct page *)page->index;
pprev = (struct page **)page->private;
pprev = (struct page **)page_private(page);
*pprev = next;
if (next)
next->private = (unsigned long)pprev;
set_page_private(next, (unsigned long)pprev);
}
void pgd_ctor(void *pgd, kmem_cache_t *cache, unsigned long unused)
......
......@@ -144,6 +144,7 @@ void destroy_context_skas(struct mm_struct *mm)
if(!proc_mm || !ptrace_faultinfo){
free_page(mmu->id.stack);
pte_lock_deinit(virt_to_page(mmu->last_page_table));
pte_free_kernel((pte_t *) mmu->last_page_table);
dec_page_state(nr_page_table_pages);
#ifdef CONFIG_3_LEVEL_PGTABLES
......
......@@ -291,8 +291,8 @@ static int afs_file_releasepage(struct page *page, gfp_t gfp_flags)
cachefs_uncache_page(vnode->cache, page);
#endif
pageio = (struct cachefs_page *) page->private;
page->private = 0;
pageio = (struct cachefs_page *) page_private(page);
set_page_private(page, 0);
ClearPagePrivate(page);
if (pageio)
......
......@@ -96,7 +96,7 @@ static void
__clear_page_buffers(struct page *page)
{
ClearPagePrivate(page);
page->private = 0;
set_page_private(page, 0);
page_cache_release(page);
}
......
......@@ -86,7 +86,7 @@ struct meta_anchor {
atomic_t io_count;
struct metapage *mp[MPS_PER_PAGE];
};
#define mp_anchor(page) ((struct meta_anchor *)page->private)
#define mp_anchor(page) ((struct meta_anchor *)page_private(page))
static inline struct metapage *page_to_mp(struct page *page, uint offset)
{
......@@ -108,7 +108,7 @@ static inline int insert_metapage(struct page *page, struct metapage *mp)
if (!a)
return -ENOMEM;
memset(a, 0, sizeof(struct meta_anchor));
page->private = (unsigned long)a;
set_page_private(page, (unsigned long)a);
SetPagePrivate(page);
kmap(page);
}
......@@ -136,7 +136,7 @@ static inline void remove_metapage(struct page *page, struct metapage *mp)
a->mp[index] = NULL;
if (--a->mp_count == 0) {
kfree(a);
page->private = 0;
set_page_private(page, 0);
ClearPagePrivate(page);
kunmap(page);
}
......@@ -156,13 +156,13 @@ static inline void dec_io(struct page *page, void (*handler) (struct page *))
#else
static inline struct metapage *page_to_mp(struct page *page, uint offset)
{
return PagePrivate(page) ? (struct metapage *)page->private : NULL;
return PagePrivate(page) ? (struct metapage *)page_private(page) : NULL;
}
static inline int insert_metapage(struct page *page, struct metapage *mp)
{
if (mp) {
page->private = (unsigned long)mp;
set_page_private(page, (unsigned long)mp);
SetPagePrivate(page);
kmap(page);
}
......@@ -171,7 +171,7 @@ static inline int insert_metapage(struct page *page, struct metapage *mp)
static inline void remove_metapage(struct page *page, struct metapage *mp)
{
page->private = 0;
set_page_private(page, 0);
ClearPagePrivate(page);
kunmap(page);
}
......
......@@ -181,8 +181,9 @@ set_page_region(
size_t offset,
size_t length)
{
page->private |= page_region_mask(offset, length);
if (page->private == ~0UL)
set_page_private(page,
page_private(page) | page_region_mask(offset, length));
if (page_private(page) == ~0UL)
SetPageUptodate(page);
}
......@@ -194,7 +195,7 @@ test_page_region(
{
unsigned long mask = page_region_mask(offset, length);
return (mask && (page->private & mask) == mask);
return (mask && (page_private(page) & mask) == mask);
}
/*
......
......@@ -126,8 +126,8 @@ BUFFER_FNS(Eopnotsupp, eopnotsupp)
/* If we *know* page->private refers to buffer_heads */
#define page_buffers(page) \
({ \
BUG_ON(!PagePrivate(page)); \
((struct buffer_head *)(page)->private); \
BUG_ON(!PagePrivate(page)); \
((struct buffer_head *)page_private(page)); \
})
#define page_has_buffers(page) PagePrivate(page)
......@@ -219,7 +219,7 @@ static inline void attach_page_buffers(struct page *page,
{
page_cache_get(page);
SetPagePrivate(page);
page->private = (unsigned long)head;
set_page_private(page, (unsigned long)head);
}
static inline void get_bh(struct buffer_head *bh)
......
......@@ -226,13 +226,18 @@ struct page {
* to show when page is mapped
* & limit reverse map searches.
*/
unsigned long private; /* Mapping-private opaque data:
union {
unsigned long private; /* Mapping-private opaque data:
* usually used for buffer_heads
* if PagePrivate set; used for
* swp_entry_t if PageSwapCache
* When page is free, this indicates
* order in the buddy system.
*/
#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
spinlock_t ptl;
#endif
} u;
struct address_space *mapping; /* If low bit clear, points to
* inode address_space, or NULL.
* If page mapped as anonymous
......@@ -260,6 +265,9 @@ struct page {
#endif /* WANT_PAGE_VIRTUAL */
};
#define page_private(page) ((page)->u.private)
#define set_page_private(page, v) ((page)->u.private = (v))
/*
* FIXME: take this include out, include page-flags.h in
* files which need it (119 of them)
......@@ -311,17 +319,17 @@ extern void FASTCALL(__page_cache_release(struct page *));
#ifdef CONFIG_HUGETLB_PAGE
static inline int page_count(struct page *p)
static inline int page_count(struct page *page)
{
if (PageCompound(p))
p = (struct page *)p->private;
return atomic_read(&(p)->_count) + 1;
if (PageCompound(page))
page = (struct page *)page_private(page);
return atomic_read(&page->_count) + 1;
}
static inline void get_page(struct page *page)
{
if (unlikely(PageCompound(page)))
page = (struct page *)page->private;
page = (struct page *)page_private(page);
atomic_inc(&page->_count);
}
......@@ -587,7 +595,7 @@ static inline int PageAnon(struct page *page)
static inline pgoff_t page_index(struct page *page)
{
if (unlikely(PageSwapCache(page)))
return page->private;
return page_private(page);
return page->index;
}
......@@ -779,9 +787,31 @@ static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long a
}
#endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */
#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
/*
* We tuck a spinlock to guard each pagetable page into its struct page,
* at page->private, with BUILD_BUG_ON to make sure that this will not
* overflow into the next struct page (as it might with DEBUG_SPINLOCK).
* When freeing, reset page->mapping so free_pages_check won't complain.
*/
#define __pte_lockptr(page) &((page)->u.ptl)
#define pte_lock_init(_page) do { \
spin_lock_init(__pte_lockptr(_page)); \
} while (0)
#define pte_lock_deinit(page) ((page)->mapping = NULL)
#define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));})
#else
/*
* We use mm->page_table_lock to guard all pagetable pages of the mm.
*/
#define pte_lock_init(page) do {} while (0)
#define pte_lock_deinit(page) do {} while (0)
#define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;})
#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
#define pte_offset_map_lock(mm, pmd, address, ptlp) \
({ \
spinlock_t *__ptl = &(mm)->page_table_lock; \
spinlock_t *__ptl = pte_lockptr(mm, pmd); \
pte_t *__pte = pte_offset_map(pmd, address); \
*(ptlp) = __ptl; \
spin_lock(__ptl); \
......
......@@ -334,7 +334,7 @@ static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order)
if (pages) {
unsigned int count, i;
pages->mapping = NULL;
pages->private = order;
set_page_private(pages, order);
count = 1 << order;
for (i = 0; i < count; i++)
SetPageReserved(pages + i);
......@@ -347,7 +347,7 @@ static void kimage_free_pages(struct page *page)
{
unsigned int order, count, i;
order = page->private;
order = page_private(page);
count = 1 << order;
for (i = 0; i < count; i++)
ClearPageReserved(page + i);
......
......@@ -111,3 +111,16 @@ config SPARSEMEM_STATIC
config SPARSEMEM_EXTREME
def_bool y
depends on SPARSEMEM && !SPARSEMEM_STATIC
# Heavily threaded applications may benefit from splitting the mm-wide
# page_table_lock, so that faults on different parts of the user address
# space can be handled with less contention: split it at this NR_CPUS.
# Default to 4 for wider testing, though 8 might be more appropriate.
# ARM's adjust_pte (unused if VIPT) depends on mm-wide page_table_lock.
# PA-RISC's debug spinlock_t is too large for the 32-bit struct page.
#
config SPLIT_PTLOCK_CPUS
int
default "4096" if ARM && !CPU_CACHE_VIPT
default "4096" if PARISC && DEBUG_SPINLOCK && !64BIT
default "4"
......@@ -152,7 +152,7 @@ static int sync_page(void *word)
* in the ->sync_page() methods make essential use of the
* page_mapping(), merely passing the page down to the backing
* device's unplug functions when it's non-NULL, which in turn
* ignore it for all cases but swap, where only page->private is
* ignore it for all cases but swap, where only page_private(page) is
* of interest. When page_mapping() does go NULL, the entire
* call stack gracefully ignores the page and returns.
* -- wli
......
......@@ -114,6 +114,7 @@ static void free_pte_range(struct mmu_gather *tlb, pmd_t *pmd)
{
struct page *page = pmd_page(*pmd);
pmd_clear(pmd);
pte_lock_deinit(page);
pte_free_tlb(tlb, page);
dec_page_state(nr_page_table_pages);
tlb->mm->nr_ptes--;
......@@ -294,10 +295,12 @@ int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address)
if (!new)
return -ENOMEM;
pte_lock_init(new);
spin_lock(&mm->page_table_lock);
if (pmd_present(*pmd)) /* Another has populated it */
if (pmd_present(*pmd)) { /* Another has populated it */
pte_lock_deinit(new);
pte_free(new);
else {
} else {
mm->nr_ptes++;
inc_page_state(nr_page_table_pages);
pmd_populate(mm, pmd, new);
......@@ -432,7 +435,7 @@ static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
if (!dst_pte)
return -ENOMEM;
src_pte = pte_offset_map_nested(src_pmd, addr);
src_ptl = &src_mm->page_table_lock;
src_ptl = pte_lockptr(src_mm, src_pmd);
spin_lock(src_ptl);
do {
......@@ -1194,15 +1197,16 @@ EXPORT_SYMBOL(remap_pfn_range);
* (but do_wp_page is only called after already making such a check;
* and do_anonymous_page and do_no_page can safely check later on).
*/
static inline int pte_unmap_same(struct mm_struct *mm,
static inline int pte_unmap_same(struct mm_struct *mm, pmd_t *pmd,
pte_t *page_table, pte_t orig_pte)
{
int same = 1;
#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
if (sizeof(pte_t) > sizeof(unsigned long)) {
spin_lock(&mm->page_table_lock);
spinlock_t *ptl = pte_lockptr(mm, pmd);
spin_lock(ptl);
same = pte_same(*page_table, orig_pte);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
}
#endif
pte_unmap(page_table);
......@@ -1655,7 +1659,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
pte_t pte;
int ret = VM_FAULT_MINOR;
if (!pte_unmap_same(mm, page_table, orig_pte))
if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
goto out;
entry = pte_to_swp_entry(orig_pte);
......@@ -1773,7 +1777,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
page_cache_get(page);
entry = mk_pte(page, vma->vm_page_prot);
ptl = &mm->page_table_lock;
ptl = pte_lockptr(mm, pmd);
spin_lock(ptl);
if (!pte_none(*page_table))
goto release;
......@@ -1934,7 +1938,7 @@ static int do_file_page(struct mm_struct *mm, struct vm_area_struct *vma,
pgoff_t pgoff;
int err;
if (!pte_unmap_same(mm, page_table, orig_pte))
if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
return VM_FAULT_MINOR;
if (unlikely(!(vma->vm_flags & VM_NONLINEAR))) {
......@@ -1992,7 +1996,7 @@ static inline int handle_pte_fault(struct mm_struct *mm,
pte, pmd, write_access, entry);
}
ptl = &mm->page_table_lock;
ptl = pte_lockptr(mm, pmd);
spin_lock(ptl);
if (unlikely(!pte_same(*pte, entry)))
goto unlock;
......
......@@ -72,7 +72,7 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
struct address_space *mapping = NULL;
struct mm_struct *mm = vma->vm_mm;
pte_t *old_pte, *new_pte, pte;
spinlock_t *old_ptl;
spinlock_t *old_ptl, *new_ptl;
if (vma->vm_file) {
/*
......@@ -88,8 +88,15 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
new_vma->vm_truncate_count = 0;
}
/*
* We don't have to worry about the ordering of src and dst
* pte locks because exclusive mmap_sem prevents deadlock.
*/
old_pte = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl);
new_pte = pte_offset_map_nested(new_pmd, new_addr);
new_ptl = pte_lockptr(mm, new_pmd);
if (new_ptl != old_ptl)
spin_lock(new_ptl);
for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE,
new_pte++, new_addr += PAGE_SIZE) {
......@@ -101,6 +108,8 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
set_pte_at(mm, new_addr, new_pte, pte);
}
if (new_ptl != old_ptl)
spin_unlock(new_ptl);
pte_unmap_nested(new_pte - 1);
pte_unmap_unlock(old_pte - 1, old_ptl);
if (mapping)
......
......@@ -154,7 +154,7 @@ static void prep_compound_page(struct page *page, unsigned long order)
struct page *p = page + i;
SetPageCompound(p);
p->private = (unsigned long)page;
set_page_private(p, (unsigned long)page);
}
}
......@@ -174,7 +174,7 @@ static void destroy_compound_page(struct page *page, unsigned long order)
if (!PageCompound(p))
bad_page(__FUNCTION__, page);
if (p->private != (unsigned long)page)
if (page_private(p) != (unsigned long)page)
bad_page(__FUNCTION__, page);
ClearPageCompound(p);
}
......@@ -187,18 +187,18 @@ static void destroy_compound_page(struct page *page, unsigned long order)
* So, we don't need atomic page->flags operations here.
*/
static inline unsigned long page_order(struct page *page) {
return page->private;
return page_private(page);
}
static inline void set_page_order(struct page *page, int order) {
page->private = order;
set_page_private(page, order);
__SetPagePrivate(page);
}
static inline void rmv_page_order(struct page *page)
{
__ClearPagePrivate(page);
page->private = 0;
set_page_private(page, 0);
}
/*
......@@ -238,7 +238,7 @@ __find_combined_index(unsigned long page_idx, unsigned int order)
* (a) the buddy is free &&
* (b) the buddy is on the buddy system &&
* (c) a page and its buddy have the same order.
* for recording page's order, we use page->private and PG_private.
* for recording page's order, we use page_private(page) and PG_private.
*
*/
static inline int page_is_buddy(struct page *page, int order)
......@@ -264,7 +264,7 @@ static inline int page_is_buddy(struct page *page, int order)
* parts of the VM system.
* At each level, we keep a list of pages, which are heads of continuous
* free pages of length of (1 << order) and marked with PG_Private.Page's
* order is recorded in page->private field.
* order is recorded in page_private(page) field.
* So when we are allocating or freeing one, we can derive the state of the
* other. That is, if we allocate a small block, and both were
* free, the remainder of the region must be split into blocks.
......@@ -463,7 +463,7 @@ static void prep_new_page(struct page *page, int order)
page->flags &= ~(1 << PG_uptodate | 1 << PG_error |
1 << PG_referenced | 1 << PG_arch_1 |
1 << PG_checked | 1 << PG_mappedtodisk);
page->private = 0;
set_page_private(page, 0);
set_page_refs(page, order);
kernel_map_pages(page, 1 << order, 1);
}
......
......@@ -91,7 +91,8 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
unlock_page(page);
goto out;
}
bio = get_swap_bio(GFP_NOIO, page->private, page, end_swap_bio_write);
bio = get_swap_bio(GFP_NOIO, page_private(page), page,
end_swap_bio_write);
if (bio == NULL) {
set_page_dirty(page);
unlock_page(page);
......@@ -115,7 +116,8 @@ int swap_readpage(struct file *file, struct page *page)
BUG_ON(!PageLocked(page));
ClearPageUptodate(page);
bio = get_swap_bio(GFP_KERNEL, page->private, page, end_swap_bio_read);
bio = get_swap_bio(GFP_KERNEL, page_private(page), page,
end_swap_bio_read);
if (bio == NULL) {
unlock_page(page);
ret = -ENOMEM;
......
......@@ -274,7 +274,7 @@ pte_t *page_check_address(struct page *page, struct mm_struct *mm,
return NULL;
}
ptl = &mm->page_table_lock;
ptl = pte_lockptr(mm, pmd);
spin_lock(ptl);
if (pte_present(*pte) && page_to_pfn(page) == pte_pfn(*pte)) {
*ptlp = ptl;
......@@ -550,7 +550,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma)
update_hiwater_rss(mm);
if (PageAnon(page)) {
swp_entry_t entry = { .val = page->private };
swp_entry_t entry = { .val = page_private(page) };
/*
* Store the swap location in the pte.
* See handle_pte_fault() ...
......
......@@ -71,9 +71,6 @@
/* Pretend that each entry is of this size in directory's i_size */
#define BOGO_DIRENT_SIZE 20
/* Keep swapped page count in private field of indirect struct page */
#define nr_swapped private
/* Flag allocation requirements to shmem_getpage and shmem_swp_alloc */
enum sgp_type {
SGP_QUICK, /* don't try more than file page cache lookup */
......@@ -324,8 +321,10 @@ static void shmem_swp_set(struct shmem_inode_info *info, swp_entry_t *entry, uns
entry->val = value;
info->swapped += incdec;
if ((unsigned long)(entry - info->i_direct) >= SHMEM_NR_DIRECT)
kmap_atomic_to_page(entry)->nr_swapped += incdec;
if ((unsigned long)(entry - info->i_direct) >= SHMEM_NR_DIRECT) {
struct page *page = kmap_atomic_to_page(entry);
set_page_private(page, page_private(page) + incdec);
}
}
/*
......@@ -368,9 +367,8 @@ static swp_entry_t *shmem_swp_alloc(struct shmem_inode_info *info, unsigned long
spin_unlock(&info->lock);
page = shmem_dir_alloc(mapping_gfp_mask(inode->i_mapping) | __GFP_ZERO);
if (page) {
page->nr_swapped = 0;
}
if (page)
set_page_private(page, 0);
spin_lock(&info->lock);
if (!page) {
......@@ -561,7 +559,7 @@ static void shmem_truncate(struct inode *inode)
diroff = 0;
}
subdir = dir[diroff];
if (subdir && subdir->nr_swapped) {
if (subdir && page_private(subdir)) {
size = limit - idx;
if (size > ENTRIES_PER_PAGE)
size = ENTRIES_PER_PAGE;
......@@ -572,10 +570,10 @@ static void shmem_truncate(struct inode *inode)
nr_swaps_freed += freed;
if (offset)
spin_lock(&info->lock);
subdir->nr_swapped -= freed;
set_page_private(subdir, page_private(subdir) - freed);
if (offset)
spin_unlock(&info->lock);
BUG_ON(subdir->nr_swapped > offset);
BUG_ON(page_private(subdir) > offset);
}
if (offset)
offset = 0;
......@@ -743,7 +741,7 @@ static int shmem_unuse_inode(struct shmem_inode_info *info, swp_entry_t entry, s
dir = shmem_dir_map(subdir);
}
subdir = *dir;
if (subdir && subdir->nr_swapped) {
if (subdir && page_private(subdir)) {
ptr = shmem_swp_map(subdir);
size = limit - idx;
if (size > ENTRIES_PER_PAGE)
......
......@@ -39,7 +39,7 @@ int page_cluster;
void put_page(struct page *page)
{
if (unlikely(PageCompound(page))) {
page = (struct page *)page->private;
page = (struct page *)page_private(page);
if (put_page_testzero(page)) {
void (*dtor)(struct page *page);
......
......@@ -83,7 +83,7 @@ static int __add_to_swap_cache(struct page *page, swp_entry_t entry,
page_cache_get(page);
SetPageLocked(page);
SetPageSwapCache(page);
page->private = entry.val;
set_page_private(page, entry.val);
total_swapcache_pages++;
pagecache_acct(1);
}
......@@ -126,8 +126,8 @@ void __delete_from_swap_cache(struct page *page)
BUG_ON(PageWriteback(page));
BUG_ON(PagePrivate(page));
radix_tree_delete(&swapper_space.page_tree, page->private);
page->private = 0;
radix_tree_delete(&swapper_space.page_tree, page_private(page));
set_page_private(page, 0);
ClearPageSwapCache(page);
total_swapcache_pages--;
pagecache_acct(-1);
......@@ -197,7 +197,7 @@ void delete_from_swap_cache(struct page *page)
{
swp_entry_t entry;
entry.val = page->private;
entry.val = page_private(page);
write_lock_irq(&swapper_space.tree_lock);
__delete_from_swap_cache(page);
......
......@@ -61,7 +61,7 @@ void swap_unplug_io_fn(struct backing_dev_info *unused_bdi, struct page *page)
swp_entry_t entry;
down_read(&swap_unplug_sem);
entry.val = page->private;
entry.val = page_private(page);
if (PageSwapCache(page)) {
struct block_device *bdev = swap_info[swp_type(entry)].bdev;
struct backing_dev_info *bdi;
......@@ -69,8 +69,8 @@ void swap_unplug_io_fn(struct backing_dev_info *unused_bdi, struct page *page)
/*
* If the page is removed from swapcache from under us (with a
* racy try_to_unuse/swapoff) we need an additional reference
* count to avoid reading garbage from page->private above. If
* the WARN_ON triggers during a swapoff it maybe the race
* count to avoid reading garbage from page_private(page) above.
* If the WARN_ON triggers during a swapoff it maybe the race
* condition and it's harmless. However if it triggers without
* swapoff it signals a problem.
*/
......@@ -294,7 +294,7 @@ static inline int page_swapcount(struct page *page)
struct swap_info_struct *p;
swp_entry_t entry;
entry.val = page->private;
entry.val = page_private(page);
p = swap_info_get(entry);
if (p) {
/* Subtract the 1 for the swap cache itself */
......@@ -339,7 +339,7 @@ int remove_exclusive_swap_page(struct page *page)
if (page_count(page) != 2) /* 2: us + cache */
return 0;
entry.val = page->private;
entry.val = page_private(page);
p = swap_info_get(entry);
if (!p)
return 0;
......@@ -1042,7 +1042,7 @@ int page_queue_congested(struct page *page)
BUG_ON(!PageLocked(page)); /* It pins the swap_info_struct */
if (PageSwapCache(page)) {
swp_entry_t entry = { .val = page->private };
swp_entry_t entry = { .val = page_private(page) };
struct swap_info_struct *sis;
sis = get_swap_info_struct(swp_type(entry));
......
......@@ -521,7 +521,7 @@ static int shrink_list(struct list_head *page_list, struct scan_control *sc)
#ifdef CONFIG_SWAP
if (PageSwapCache(page)) {
swp_entry_t swap = { .val = page->private };
swp_entry_t swap = { .val = page_private(page) };
__delete_from_swap_cache(page);
write_unlock_irq(&mapping->tree_lock);
swap_free(swap);
......
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