mm: Fix sparse warnings in backing-dev.h
Commit Message
Sparse reports a context imbalance, and indeed _begin() returns
with the RCU lock held and _end() releases it. Reassure sparse that
this is fine by adding appropriate annotations.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
include/linux/backing-dev.h | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
Comments
On Fri, Jun 23, 2023 at 06:07:37PM +0100, Matthew Wilcox (Oracle) wrote:
> Sparse reports a context imbalance, and indeed _begin() returns
> with the RCU lock held and _end() releases it. Reassure sparse that
> this is fine by adding appropriate annotations.
Please ignore; I failed to drive my tools correctly.
@@ -284,8 +284,9 @@ static inline struct bdi_writeback *inode_to_wb_wbc(
* can't sleep during the transaction. IRQs may or may not be disabled on
* return.
*/
-static inline struct bdi_writeback *
-unlocked_inode_to_wb_begin(struct inode *inode, struct wb_lock_cookie *cookie)
+static inline
+struct bdi_writeback *unlocked_inode_to_wb_begin(struct inode *inode,
+ struct wb_lock_cookie *cookie) __acquires(RCU)
{
rcu_read_lock();
@@ -311,7 +312,7 @@ unlocked_inode_to_wb_begin(struct inode *inode, struct wb_lock_cookie *cookie)
* @cookie: @cookie from unlocked_inode_to_wb_begin()
*/
static inline void unlocked_inode_to_wb_end(struct inode *inode,
- struct wb_lock_cookie *cookie)
+ struct wb_lock_cookie *cookie) __releases(RCU)
{
if (unlikely(cookie->locked))
xa_unlock_irqrestore(&inode->i_mapping->i_pages, cookie->flags);