[RFC 11/12] lockdep: Call lock_acquire(release) when accessing PG_locked manually

[Byungchul Park]

The PG_locked bit can be updated through SetPageLocked() or
ClearPageLocked(), not by lock_page() and unlock_page().
SetPageLockded() and ClearPageLocked() also have to be considered to
get balanced between acquring and releasing the PG_locked lock.

Signed-off-by: Byungchul Park 
---
 fs/cifs/file.c  | 4 
 include/linux/pagemap.h | 5 -
 mm/filemap.c| 6 --
 mm/ksm.c| 1 +
 mm/migrate.c| 1 +
 mm/shmem.c  | 2 ++
 mm/swap_state.c | 2 ++
 mm/vmscan.c | 1 +
 8 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index bcf9ead..7b250c1 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3392,12 +3392,14 @@ readpages_get_pages(struct address_space *mapping, 
struct list_head *page_list,
 * PG_locked without checking it first.
 */
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
rc = add_to_page_cache_locked(page, mapping,
  page->index, gfp);
 
/* give up if we can't stick it in the cache */
if (rc) {
__ClearPageLocked(page);
+   lock_page_release(page);
return rc;
}
 
@@ -3419,8 +3421,10 @@ readpages_get_pages(struct address_space *mapping, 
struct list_head *page_list,
break;
 
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
if (add_to_page_cache_locked(page, mapping, page->index, gfp)) {
__ClearPageLocked(page);
+   lock_page_release(page);
break;
}
list_move_tail(>lru, tmplist);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 2fc4af1..f92972c 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -760,9 +760,12 @@ static inline int add_to_page_cache(struct page *page,
int error;
 
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
error = add_to_page_cache_locked(page, mapping, offset, gfp_mask);
-   if (unlikely(error))
+   if (unlikely(error)) {
__ClearPageLocked(page);
+   lock_page_release(page);
+   }
return error;
 }
 
diff --git a/mm/filemap.c b/mm/filemap.c
index 47fc5c0..7acce5e 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -690,11 +690,13 @@ int add_to_page_cache_lru(struct page *page, struct 
address_space *mapping,
int ret;
 
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
ret = __add_to_page_cache_locked(page, mapping, offset,
 gfp_mask, );
-   if (unlikely(ret))
+   if (unlikely(ret)) {
__ClearPageLocked(page);
-   else {
+   lock_page_release(page);
+   } else {
/*
 * The page might have been evicted from cache only
 * recently, in which case it should be activated like
diff --git a/mm/ksm.c b/mm/ksm.c
index ca6d2a0..c89debd 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1869,6 +1869,7 @@ struct page *ksm_might_need_to_copy(struct page *page,
SetPageDirty(new_page);
__SetPageUptodate(new_page);
__SetPageLocked(new_page);
+   lock_page_acquire(new_page, 1);
}
 
return new_page;
diff --git a/mm/migrate.c b/mm/migrate.c
index 3ad0fea..9aab7c4 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1773,6 +1773,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
 
/* Prepare a page as a migration target */
__SetPageLocked(new_page);
+   lock_page_acquire(new_page, 1);
SetPageSwapBacked(new_page);
 
/* anon mapping, we can simply copy page->mapping to the new page: */
diff --git a/mm/shmem.c b/mm/shmem.c
index 440e2a7..da35ca8 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1090,6 +1090,7 @@ static int shmem_replace_page(struct page **pagep, gfp_t 
gfp,
flush_dcache_page(newpage);
 
__SetPageLocked(newpage);
+   lock_page_acquire(newpage, 1);
SetPageUptodate(newpage);
SetPageSwapBacked(newpage);
set_page_private(newpage, swap_index);
@@ -1283,6 +1284,7 @@ repeat:
 
__SetPageSwapBacked(page);
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
if (sgp == SGP_WRITE)
__SetPageReferenced(page);
 
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 3fb7013..200edbf 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -358,6 +358,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, 
gfp_t gfp_mask,
 
/* May fail (-ENOMEM) if radix-tree node allocation failed. */
__SetPageLocked(new_page);
+   lock_page_acquire(new_page, 1);
SetPageSwapBacked(new_page);
 

[RFC 11/12] lockdep: Call lock_acquire(release) when accessing PG_locked manually

[Byungchul Park]

The PG_locked bit can be updated through SetPageLocked() or
ClearPageLocked(), not by lock_page() and unlock_page().
SetPageLockded() and ClearPageLocked() also have to be considered to
get balanced between acquring and releasing the PG_locked lock.

Signed-off-by: Byungchul Park 
---
 fs/cifs/file.c  | 4 
 include/linux/pagemap.h | 5 -
 mm/filemap.c| 6 --
 mm/ksm.c| 1 +
 mm/migrate.c| 1 +
 mm/shmem.c  | 2 ++
 mm/swap_state.c | 2 ++
 mm/vmscan.c | 1 +
 8 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index bcf9ead..7b250c1 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3392,12 +3392,14 @@ readpages_get_pages(struct address_space *mapping, 
struct list_head *page_list,
 * PG_locked without checking it first.
 */
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
rc = add_to_page_cache_locked(page, mapping,
  page->index, gfp);
 
/* give up if we can't stick it in the cache */
if (rc) {
__ClearPageLocked(page);
+   lock_page_release(page);
return rc;
}
 
@@ -3419,8 +3421,10 @@ readpages_get_pages(struct address_space *mapping, 
struct list_head *page_list,
break;
 
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
if (add_to_page_cache_locked(page, mapping, page->index, gfp)) {
__ClearPageLocked(page);
+   lock_page_release(page);
break;
}
list_move_tail(>lru, tmplist);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 2fc4af1..f92972c 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -760,9 +760,12 @@ static inline int add_to_page_cache(struct page *page,
int error;
 
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
error = add_to_page_cache_locked(page, mapping, offset, gfp_mask);
-   if (unlikely(error))
+   if (unlikely(error)) {
__ClearPageLocked(page);
+   lock_page_release(page);
+   }
return error;
 }
 
diff --git a/mm/filemap.c b/mm/filemap.c
index 47fc5c0..7acce5e 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -690,11 +690,13 @@ int add_to_page_cache_lru(struct page *page, struct 
address_space *mapping,
int ret;
 
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
ret = __add_to_page_cache_locked(page, mapping, offset,
 gfp_mask, );
-   if (unlikely(ret))
+   if (unlikely(ret)) {
__ClearPageLocked(page);
-   else {
+   lock_page_release(page);
+   } else {
/*
 * The page might have been evicted from cache only
 * recently, in which case it should be activated like
diff --git a/mm/ksm.c b/mm/ksm.c
index ca6d2a0..c89debd 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1869,6 +1869,7 @@ struct page *ksm_might_need_to_copy(struct page *page,
SetPageDirty(new_page);
__SetPageUptodate(new_page);
__SetPageLocked(new_page);
+   lock_page_acquire(new_page, 1);
}
 
return new_page;
diff --git a/mm/migrate.c b/mm/migrate.c
index 3ad0fea..9aab7c4 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1773,6 +1773,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
 
/* Prepare a page as a migration target */
__SetPageLocked(new_page);
+   lock_page_acquire(new_page, 1);
SetPageSwapBacked(new_page);
 
/* anon mapping, we can simply copy page->mapping to the new page: */
diff --git a/mm/shmem.c b/mm/shmem.c
index 440e2a7..da35ca8 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1090,6 +1090,7 @@ static int shmem_replace_page(struct page **pagep, gfp_t 
gfp,
flush_dcache_page(newpage);
 
__SetPageLocked(newpage);
+   lock_page_acquire(newpage, 1);
SetPageUptodate(newpage);
SetPageSwapBacked(newpage);
set_page_private(newpage, swap_index);
@@ -1283,6 +1284,7 @@ repeat:
 
__SetPageSwapBacked(page);
__SetPageLocked(page);
+   lock_page_acquire(page, 1);
if (sgp == SGP_WRITE)
__SetPageReferenced(page);
 
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 3fb7013..200edbf 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -358,6 +358,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, 
gfp_t gfp_mask,
 
/* May fail (-ENOMEM) if radix-tree node allocation failed. */
__SetPageLocked(new_page);
+   lock_page_acquire(new_page, 1);
SetPageSwapBacked(new_page);
err =