f2fs: move f2fs to use reader-unfair rwsems
f2fs rw_semaphores work better if writers can starve readers,
especially for the checkpoint thread, because writers are strictly
more important than reader threads. This prevents significant priority
inversion between low-priority readers that blocked while trying to
acquire the read lock and a second acquisition of the write lock that
might be blocking high priority work.
Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/verity.c b/fs/f2fs/verity.c
index fe5acdc..3d79320 100644
--- a/fs/f2fs/verity.c
+++ b/fs/f2fs/verity.c
@@ -208,7 +208,7 @@ static int f2fs_end_enable_verity(struct file *filp, const void *desc,
* from re-instantiating cached pages we are truncating (since unlike
* normal file accesses, garbage collection isn't limited by i_size).
*/
- down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+ f2fs_down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
truncate_inode_pages(inode->i_mapping, inode->i_size);
err2 = f2fs_truncate(inode);
if (err2) {
@@ -216,7 +216,7 @@ static int f2fs_end_enable_verity(struct file *filp, const void *desc,
err2);
set_sbi_flag(sbi, SBI_NEED_FSCK);
}
- up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+ f2fs_up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
clear_inode_flag(inode, FI_VERITY_IN_PROGRESS);
return err ?: err2;
}
