[patch 1/2] mm: page trylock rename

Nick Piggin
2007-11-10T05:12:34Z

Hi,

OK minus the memory barrier changes for now. Can we possibly please
get these into 2.6.24?

--
mm: rename page trylock

Converting page lock to new locking bitops requires a change of page flag
operation naming, so we might as well convert it to something nicer
(!TestSetPageLocked => trylock_page, SetPageLocked => set_page_locked).

Signed-off-by: Nick Piggin <npiggin@suse.de>

---
drivers/scsi/sg.c | 2 +-
fs/afs/write.c | 2 +-
fs/cifs/file.c | 2 +-
fs/jbd/commit.c | 2 +-
fs/jbd2/commit.c | 2 +-
fs/reiserfs/journal.c | 2 +-
fs/splice.c | 2 +-
fs/xfs/linux-2.6/xfs_aops.c | 4 ++--
include/linux/page-flags.h | 8 --------
include/linux/pagemap.h | 19 +++++++++++++++++--
mm/filemap.c | 12 ++++++------
mm/memory.c | 2 +-
mm/migrate.c | 4 ++--
mm/rmap.c | 2 +-
mm/shmem.c | 4 ++--
mm/swap.c | 2 +-
mm/swap_state.c | 6 +++---
mm/swapfile.c | 2 +-
mm/truncate.c | 4 ++--
mm/vmscan.c | 4 ++--
20 files changed, 47 insertions(+), 40 deletions(-)

Index: linux-2.6/include/linux/pagemap.h
===================================================================
--- linux-2.6.orig/include/linux/pagemap.h
+++ linux-2.6/include/linux/pagemap.h
@@ -160,13 +160,28 @@ extern void FASTCALL(__lock_page(struct
extern void FASTCALL(__lock_page_nosync(struct page *page));
extern void FASTCALL(unlock_page(struct page *page));

+static inline void set_page_locked(struct page *page)
+{
+ set_bit(PG_locked, &page->flags);
+}
+
+static inline void clear_page_locked(struct page *page)
+{
+ clear_bit(PG_locked, &page->flags);
+}
+
+static inline int trylock_page(struct page *page)
+{
+ return !test_and_set_bit(PG_locked, &page->flags);
+}
+
/*
* lock_page may only be called if we have the page's inode pinned.
*/
static inline void lock_page(struct page *page)
{
might_sleep();
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
__lock_page(page);
}

@@ -177,7 +192,7 @@ static inline void lock_page(struct page
static inline void lock_page_nosync(struct page *page)
{
might_sleep();
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
__lock_page_nosync(page);
}

Index: linux-2.6/drivers/scsi/sg.c
===================================================================
--- linux-2.6.orig/drivers/scsi/sg.c
+++ linux-2.6/drivers/scsi/sg.c
@@ -1714,7 +1714,7 @@ st_map_user_pages(struct scatterlist *sg
*/
flush_dcache_page(pages[i]);
/* ?? Is locking needed? I don't think so */
- /* if (TestSetPageLocked(pages[i]))
+ /* if (!trylock_page(pages[i]))
goto out_unlock; */
}

Index: linux-2.6/fs/cifs/file.c
===================================================================
--- linux-2.6.orig/fs/cifs/file.c
+++ linux-2.6/fs/cifs/file.c
@@ -1251,7 +1251,7 @@ retry:

if (first < 0)
lock_page(page);
- else if (TestSetPageLocked(page))
+ else if (!trylock_page(page))
break;

if (unlikely(page->mapping != mapping)) {
Index: linux-2.6/fs/jbd/commit.c
===================================================================
--- linux-2.6.orig/fs/jbd/commit.c
+++ linux-2.6/fs/jbd/commit.c
@@ -63,7 +63,7 @@ static void release_buffer_page(struct b
goto nope;

/* OK, it's a truncated page */
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto nope;

page_cache_get(page);
Index: linux-2.6/fs/jbd2/commit.c
===================================================================
--- linux-2.6.orig/fs/jbd2/commit.c
+++ linux-2.6/fs/jbd2/commit.c
@@ -63,7 +63,7 @@ static void release_buffer_page(struct b
goto nope;

/* OK, it's a truncated page */
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto nope;

page_cache_get(page);
Index: linux-2.6/fs/xfs/linux-2.6/xfs_aops.c
===================================================================
--- linux-2.6.orig/fs/xfs/linux-2.6/xfs_aops.c
+++ linux-2.6/fs/xfs/linux-2.6/xfs_aops.c
@@ -659,7 +659,7 @@ xfs_probe_cluster(
} else
pg_offset = PAGE_CACHE_SIZE;

- if (page->index == tindex && !TestSetPageLocked(page)) {
+ if (page->index == tindex && trylock_page(page)) {
pg_len = xfs_probe_page(page, pg_offset, mapped);
unlock_page(page);
}
@@ -743,7 +743,7 @@ xfs_convert_page(

if (page->index != tindex)
goto fail;
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto fail;
if (PageWriteback(page))
goto fail_unlock_page;
Index: linux-2.6/include/linux/page-flags.h
===================================================================
--- linux-2.6.orig/include/linux/page-flags.h
+++ linux-2.6/include/linux/page-flags.h
@@ -113,14 +113,6 @@
*/
#define PageLocked(page) \
test_bit(PG_locked, &(page)->flags)
-#define SetPageLocked(page) \
- set_bit(PG_locked, &(page)->flags)
-#define TestSetPageLocked(page) \
- test_and_set_bit(PG_locked, &(page)->flags)
-#define ClearPageLocked(page) \
- clear_bit(PG_locked, &(page)->flags)
-#define TestClearPageLocked(page) \
- test_and_clear_bit(PG_locked, &(page)->flags)

#define PageError(page) test_bit(PG_error, &(page)->flags)
#define SetPageError(page) set_bit(PG_error, &(page)->flags)
Index: linux-2.6/mm/memory.c
===================================================================
--- linux-2.6.orig/mm/memory.c
+++ linux-2.6/mm/memory.c
@@ -1559,7 +1559,7 @@ static int do_wp_page(struct mm_struct *
* not dirty accountable.
*/
if (PageAnon(old_page)) {
- if (!TestSetPageLocked(old_page)) {
+ if (trylock_page(old_page)) {
reuse = can_share_swap_page(old_page);
unlock_page(old_page);
}
Index: linux-2.6/mm/migrate.c
===================================================================
--- linux-2.6.orig/mm/migrate.c
+++ linux-2.6/mm/migrate.c
@@ -569,7 +569,7 @@ static int move_to_new_page(struct page
* establishing additional references. We are the only one
* holding a reference to the new page at this point.
*/
- if (TestSetPageLocked(newpage))
+ if (!trylock_page(newpage))
BUG();

/* Prepare mapping for the new page.*/
@@ -622,7 +622,7 @@ static int unmap_and_move(new_page_t get
goto move_newpage;

rc = -EAGAIN;
- if (TestSetPageLocked(page)) {
+ if (!trylock_page(page)) {
if (!force)
goto move_newpage;
lock_page(page);
Index: linux-2.6/mm/rmap.c
===================================================================
--- linux-2.6.orig/mm/rmap.c
+++ linux-2.6/mm/rmap.c
@@ -401,7 +401,7 @@ int page_referenced(struct page *page, i
referenced += page_referenced_anon(page);
else if (is_locked)
referenced += page_referenced_file(page);
- else if (TestSetPageLocked(page))
+ else if (!trylock_page(page))
referenced++;
else {
if (page->mapping)
Index: linux-2.6/mm/shmem.c
===================================================================
--- linux-2.6.orig/mm/shmem.c
+++ linux-2.6/mm/shmem.c
@@ -1182,7 +1182,7 @@ repeat:
}

/* We have to do this with page locked to prevent races */
- if (TestSetPageLocked(swappage)) {
+ if (!trylock_page(swappage)) {
shmem_swp_unmap(entry);
spin_unlock(&info->lock);
wait_on_page_locked(swappage);
@@ -1241,7 +1241,7 @@ repeat:
shmem_swp_unmap(entry);
filepage = find_get_page(mapping, idx);
if (filepage &&
- (!PageUptodate(filepage) || TestSetPageLocked(filepage))) {
+ (!PageUptodate(filepage) || !trylock_page(filepage))) {
spin_unlock(&info->lock);
wait_on_page_locked(filepage);
page_cache_release(filepage);
Index: linux-2.6/mm/swap.c
===================================================================
--- linux-2.6.orig/mm/swap.c
+++ linux-2.6/mm/swap.c
@@ -455,7 +455,7 @@ void pagevec_strip(struct pagevec *pvec)
for (i = 0; i < pagevec_count(pvec); i++) {
struct page *page = pvec->pages[i];

- if (PagePrivate(page) && !TestSetPageLocked(page)) {
+ if (PagePrivate(page) && trylock_page(page)) {
if (PagePrivate(page))
try_to_release_page(page, 0);
unlock_page(page);
Index: linux-2.6/mm/swap_state.c
===================================================================
--- linux-2.6.orig/mm/swap_state.c
+++ linux-2.6/mm/swap_state.c
@@ -104,13 +104,13 @@ static int add_to_swap_cache(struct page
INC_CACHE_INFO(noent_race);
return -ENOENT;
}
- SetPageLocked(page);
+ set_page_locked(page);
error = __add_to_swap_cache(page, entry, GFP_KERNEL);
/*
* Anon pages are already on the LRU, we don't run lru_cache_add here.
*/
if (error) {
- ClearPageLocked(page);
+ clear_page_locked(page);
swap_free(entry);
if (error == -EEXIST)
INC_CACHE_INFO(exist_race);
@@ -255,7 +255,7 @@ int move_from_swap_cache(struct page *pa
*/
static inline void free_swap_cache(struct page *page)
{
- if (PageSwapCache(page) && !TestSetPageLocked(page)) {
+ if (PageSwapCache(page) && trylock_page(page)) {
remove_exclusive_swap_page(page);
unlock_page(page);
}
Index: linux-2.6/mm/swapfile.c
===================================================================
--- linux-2.6.orig/mm/swapfile.c
+++ linux-2.6/mm/swapfile.c
@@ -401,7 +401,7 @@ void free_swap_and_cache(swp_entry_t ent
if (p) {
if (swap_entry_free(p, swp_offset(entry)) == 1) {
page = find_get_page(&swapper_space, entry.val);
- if (page && unlikely(TestSetPageLocked(page))) {
+ if (page && unlikely(!trylock_page(page))) {
page_cache_release(page);
page = NULL;
}
Index: linux-2.6/mm/truncate.c
===================================================================
--- linux-2.6.orig/mm/truncate.c
+++ linux-2.6/mm/truncate.c
@@ -189,7 +189,7 @@ void truncate_inode_pages_range(struct a
if (page_index > next)
next = page_index;
next++;
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
continue;
if (PageWriteback(page)) {
unlock_page(page);
@@ -282,7 +282,7 @@ unsigned long __invalidate_mapping_pages
pgoff_t index;
int lock_failed;

- lock_failed = TestSetPageLocked(page);
+ lock_failed = !trylock_page(page);

/*
* We really shouldn't be looking at the ->index of an
Index: linux-2.6/mm/vmscan.c
===================================================================
--- linux-2.6.orig/mm/vmscan.c
+++ linux-2.6/mm/vmscan.c
@@ -461,7 +461,7 @@ static unsigned long shrink_page_list(st
page = lru_to_page(page_list);
list_del(&page->lru);

- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto keep;

VM_BUG_ON(PageActive(page));
@@ -547,7 +547,7 @@ static unsigned long shrink_page_list(st
* A synchronous write - probably a ramdisk. Go
* ahead and try to reclaim the page.
*/
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto keep;
if (PageDirty(page) || PageWriteback(page))
goto keep_locked;
Index: linux-2.6/mm/filemap.c
===================================================================
--- linux-2.6.orig/mm/filemap.c
+++ linux-2.6/mm/filemap.c
@@ -433,7 +433,7 @@ int filemap_write_and_wait_range(struct
* @gfp_mask: page allocation mode
*
* This function is used to add newly allocated pagecache pages;
- * the page is new, so we can just run SetPageLocked() against it.
+ * the page is new, so we can just run set_page_locked() against it.
* The other page state flags were set by rmqueue().
*
* This function does not add the page to the LRU. The caller must do that.
@@ -448,7 +448,7 @@ int add_to_page_cache(struct page *page,
error = radix_tree_insert(&mapping->page_tree, offset, page);
if (!error) {
page_cache_get(page);
- SetPageLocked(page);
+ set_page_locked(page);
page->mapping = mapping;
page->index = offset;
mapping->nrpages++;
@@ -530,14 +530,14 @@ EXPORT_SYMBOL(wait_on_page_bit);
* But that's OK - sleepers in wait_on_page_writeback() just go back to sleep.
*
* The first mb is necessary to safely close the critical section opened by the
- * TestSetPageLocked(), the second mb is necessary to enforce ordering between
+ * trylock_page(), the second mb is necessary to enforce ordering between
* the clear_bit and the read of the waitqueue (to avoid SMP races with a
* parallel wait_on_page_locked()).
*/
void fastcall unlock_page(struct page *page)
{
smp_mb__before_clear_bit();
- if (!TestClearPageLocked(page))
+ if (!test_and_clear_bit(PG_locked, &page->flags))
BUG();
smp_mb__after_clear_bit();
wake_up_page(page, PG_locked);
@@ -629,7 +629,7 @@ repeat:
page = radix_tree_lookup(&mapping->page_tree, offset);
if (page) {
page_cache_get(page);
- if (TestSetPageLocked(page)) {
+ if (!trylock_page(page)) {
read_unlock_irq(&mapping->tree_lock);
__lock_page(page);

@@ -801,7 +801,7 @@ grab_cache_page_nowait(struct address_sp
struct page *page = find_get_page(mapping, index);

if (page) {
- if (!TestSetPageLocked(page))
+ if (trylock_page(page))
return page;
page_cache_release(page);
return NULL;
Index: linux-2.6/fs/splice.c
===================================================================
--- linux-2.6.orig/fs/splice.c
+++ linux-2.6/fs/splice.c
@@ -364,7 +364,7 @@ __generic_file_splice_read(struct file *
* for an in-flight io page
*/
if (flags & SPLICE_F_NONBLOCK) {
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
break;
} else
lock_page(page);
Index: linux-2.6/fs/afs/write.c
===================================================================
--- linux-2.6.orig/fs/afs/write.c
+++ linux-2.6/fs/afs/write.c
@@ -404,7 +404,7 @@ static int afs_write_back_from_locked_pa
page = pages[loop];
if (page->index > wb->last)
break;
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
break;
if (!PageDirty(page) ||
page_private(page) != (unsigned long) wb) {
Index: linux-2.6/fs/reiserfs/journal.c
===================================================================
--- linux-2.6.orig/fs/reiserfs/journal.c
+++ linux-2.6/fs/reiserfs/journal.c
@@ -629,7 +629,7 @@ static int journal_list_still_alive(stru
static void release_buffer_page(struct buffer_head *bh)
{
struct page *page = bh->b_page;
- if (!page->mapping && !TestSetPageLocked(page)) {
+ if (!page->mapping && trylock_page(page)) {
page_cache_get(page);
put_bh(bh);
if (!page->mapping)