f2fs: rework fault injection handling to avoid a warning

When CONFIG_F2FS_FAULT_INJECTION is disabled, we get a warning about an
unused label:

fs/f2fs/segment.c: In function '__submit_discard_cmd':
fs/f2fs/segment.c:1059:1: error: label 'submit' defined but not used [-Werror=unused-label]

This could be fixed by adding another #ifdef around it, but the more
reliable way of doing this seems to be to remove the other #ifdefs
where that is easily possible.

By defining time_to_inject() as a trivial stub, most of the checks for
CONFIG_F2FS_FAULT_INJECTION can go away. This also leads to nicer
formatting of the code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index fc2c98b..6908896 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -659,12 +659,11 @@ void f2fs_evict_inode(struct inode *inode)
 	if (F2FS_HAS_BLOCKS(inode))
 		err = f2fs_truncate(inode);
 
-#ifdef CONFIG_F2FS_FAULT_INJECTION
 	if (time_to_inject(sbi, FAULT_EVICT_INODE)) {
 		f2fs_show_injection_info(FAULT_EVICT_INODE);
 		err = -EIO;
 	}
-#endif
+
 	if (!err) {
 		f2fs_lock_op(sbi);
 		err = f2fs_remove_inode_page(inode);