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_Lock => trylock_page, SetPageLocked => set_page_locked).
This also facilitates lockdeping of page lock.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index d3b8ebb..3d36270 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1747,7 +1747,7 @@
*/
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; */
}
diff --git a/fs/afs/write.c b/fs/afs/write.c
index 9a849ad..065b4e1 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -404,7 +404,7 @@
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) {
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 0aac824..e692c42 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1280,7 +1280,7 @@
if (first < 0)
lock_page(page);
- else if (TestSetPageLocked(page))
+ else if (!trylock_page(page))
break;
if (unlikely(page->mapping != mapping)) {
diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c
index 2eccbfa..81a9ad71 100644
--- a/fs/jbd/commit.c
+++ b/fs/jbd/commit.c
@@ -63,7 +63,7 @@
goto nope;
/* OK, it's a truncated page */
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto nope;
page_cache_get(page);
@@ -446,7 +446,7 @@
spin_lock(&journal->j_list_lock);
}
if (unlikely(!buffer_uptodate(bh))) {
- if (TestSetPageLocked(bh->b_page)) {
+ if (!trylock_page(bh->b_page)) {
spin_unlock(&journal->j_list_lock);
lock_page(bh->b_page);
spin_lock(&journal->j_list_lock);
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index adf0395..f2ad061 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -67,7 +67,7 @@
goto nope;
/* OK, it's a truncated page */
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto nope;
page_cache_get(page);
diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index c8f60ee..ce2208b 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -627,7 +627,7 @@
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)
diff --git a/fs/splice.c b/fs/splice.c
index b30311b..1bbc6f4 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -371,7 +371,7 @@
* for an in-flight io page
*/
if (flags & SPLICE_F_NONBLOCK) {
- if (TestSetPageLocked(page)) {
+ if (!trylock_page(page)) {
error = -EAGAIN;
break;
}
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 0b211cb..fa73179 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -675,7 +675,7 @@
} 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);
}
@@ -759,7 +759,7 @@
if (page->index != tindex)
goto fail;
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto fail;
if (PageWriteback(page))
goto fail_unlock_page;
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 25aaccd..c74d3e8 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -163,7 +163,7 @@
struct page; /* forward declaration */
-PAGEFLAG(Locked, locked) TESTSCFLAG(Locked, locked)
+TESTPAGEFLAG(Locked, locked)
PAGEFLAG(Error, error)
PAGEFLAG(Referenced, referenced) TESTCLEARFLAG(Referenced, referenced)
PAGEFLAG(Dirty, dirty) TESTSCFLAG(Dirty, dirty) __CLEARPAGEFLAG(Dirty, dirty)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 69ed3cb..5da31c1 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -250,29 +250,6 @@
return read_cache_page(mapping, index, filler, data);
}
-int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
- pgoff_t index, gfp_t gfp_mask);
-int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
- pgoff_t index, gfp_t gfp_mask);
-extern void remove_from_page_cache(struct page *page);
-extern void __remove_from_page_cache(struct page *page);
-
-/*
- * Like add_to_page_cache_locked, but used to add newly allocated pages:
- * the page is new, so we can just run SetPageLocked() against it.
- */
-static inline int add_to_page_cache(struct page *page,
- struct address_space *mapping, pgoff_t offset, gfp_t gfp_mask)
-{
- int error;
-
- SetPageLocked(page);
- error = add_to_page_cache_locked(page, mapping, offset, gfp_mask);
- if (unlikely(error))
- ClearPageLocked(page);
- return error;
-}
-
/*
* Return byte-offset into filesystem object for page.
*/
@@ -294,13 +271,28 @@
extern void __lock_page_nosync(struct page *page);
extern void 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);
}
@@ -312,7 +304,7 @@
static inline int lock_page_killable(struct page *page)
{
might_sleep();
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
return __lock_page_killable(page);
return 0;
}
@@ -324,7 +316,7 @@
static inline void lock_page_nosync(struct page *page)
{
might_sleep();
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
__lock_page_nosync(page);
}
@@ -409,4 +401,27 @@
return ret;
}
+int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
+ pgoff_t index, gfp_t gfp_mask);
+int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
+ pgoff_t index, gfp_t gfp_mask);
+extern void remove_from_page_cache(struct page *page);
+extern void __remove_from_page_cache(struct page *page);
+
+/*
+ * Like add_to_page_cache_locked, but used to add newly allocated pages:
+ * the page is new, so we can just run set_page_locked() against it.
+ */
+static inline int add_to_page_cache(struct page *page,
+ struct address_space *mapping, pgoff_t offset, gfp_t gfp_mask)
+{
+ int error;
+
+ set_page_locked(page);
+ error = add_to_page_cache_locked(page, mapping, offset, gfp_mask);
+ if (unlikely(error))
+ clear_page_locked(page);
+ return error;
+}
+
#endif /* _LINUX_PAGEMAP_H */
diff --git a/mm/filemap.c b/mm/filemap.c
index d97d1ad..54e9686 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -558,14 +558,14 @@
* 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
- * the clear_bit and the read of the waitqueue (to avoid SMP races with a
- * parallel wait_on_page_locked()).
+ * test_and_set_bit() to lock the 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 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);
@@ -931,7 +931,7 @@
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;
@@ -1027,7 +1027,7 @@
if (inode->i_blkbits == PAGE_CACHE_SHIFT ||
!mapping->a_ops->is_partially_uptodate)
goto page_not_up_to_date;
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto page_not_up_to_date;
if (!mapping->a_ops->is_partially_uptodate(page,
desc, offset))
diff --git a/mm/memory.c b/mm/memory.c
index a472bcd..1002f47 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1789,7 +1789,7 @@
* 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);
}
diff --git a/mm/migrate.c b/mm/migrate.c
index 153572f..2a80136 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -605,7 +605,7 @@
* 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.*/
@@ -667,7 +667,7 @@
BUG_ON(charge);
rc = -EAGAIN;
- if (TestSetPageLocked(page)) {
+ if (!trylock_page(page)) {
if (!force)
goto move_newpage;
lock_page(page);
diff --git a/mm/rmap.c b/mm/rmap.c
index 94a5246..1ea4e6f 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -422,7 +422,7 @@
referenced += page_referenced_anon(page, mem_cont);
else if (is_locked)
referenced += page_referenced_file(page, mem_cont);
- else if (TestSetPageLocked(page))
+ else if (!trylock_page(page))
referenced++;
else {
if (page->mapping)
diff --git a/mm/shmem.c b/mm/shmem.c
index c1e5a3b..04fb4f1 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1265,7 +1265,7 @@
}
/* 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);
@@ -1329,7 +1329,7 @@
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);
diff --git a/mm/swap.c b/mm/swap.c
index 7417a2a..9e0cb31 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -444,7 +444,7 @@
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);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index b8035b0..167cf2d 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -201,7 +201,7 @@
*/
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);
}
@@ -302,9 +302,9 @@
* re-using the just freed swap entry for an existing page.
* May fail (-ENOMEM) if radix-tree node allocation failed.
*/
- SetPageLocked(new_page);
+ set_page_locked(new_page);
err = add_to_swap_cache(new_page, entry, gfp_mask & GFP_KERNEL);
- if (!err) {
+ if (likely(!err)) {
/*
* Initiate read into locked page and return.
*/
@@ -312,7 +312,7 @@
swap_readpage(NULL, new_page);
return new_page;
}
- ClearPageLocked(new_page);
+ clear_page_locked(new_page);
swap_free(entry);
} while (err != -ENOMEM);
diff --git a/mm/swapfile.c b/mm/swapfile.c
index bb7f796..1e330f2 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -403,7 +403,7 @@
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;
}
diff --git a/mm/truncate.c b/mm/truncate.c
index 894e9a7..2505050 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -187,7 +187,7 @@
if (page_index > next)
next = page_index;
next++;
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
continue;
if (PageWriteback(page)) {
unlock_page(page);
@@ -280,7 +280,7 @@
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
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 75be453..1ff1a58 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -496,7 +496,7 @@
page = lru_to_page(page_list);
list_del(&page->lru);
- if (TestSetPageLocked(page))
+ if (!trylock_page(page))
goto keep;
VM_BUG_ON(PageActive(page));
@@ -582,7 +582,7 @@
* 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;