f2fs: avoid readahead race condition
If two readahead threads having same offset enter in readpages, every read
IOs are split and issued to the disk which giving lower bandwidth.
This patch tries to avoid redundant readahead calls.
Fixes one build error reported by Randy.
Fix build error when F2FS_FS_COMPRESSION is not set/enabled.
This label is needed in either case.
../fs/f2fs/data.c: In function ‘f2fs_mpage_readpages’:
../fs/f2fs/data.c:2327:5: error: label ‘next_page’ used but not defined
goto next_page;
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 4f1f1a3..c98a918 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -794,6 +794,7 @@ struct f2fs_inode_info {
struct list_head inmem_pages; /* inmemory pages managed by f2fs */
struct task_struct *inmem_task; /* store inmemory task */
struct mutex inmem_lock; /* lock for inmemory pages */
+ pgoff_t ra_offset; /* ongoing readahead offset */
struct extent_tree *extent_tree; /* cached extent_tree entry */
/* avoid racing between foreground op and gc */