f2fs: show simple call stack in fault injection message

Previously kernel message can show that in which function we do the
injection, but unfortunately, most of the caller are the same, for
tracking more information of injection path, it needs to show upper
caller's name. This patch supports that ability.

Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 54aa30e..295a223 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -549,8 +549,10 @@ int f2fs_add_regular_entry(struct inode *dir, const struct qstr *new_name,
 
 start:
 #ifdef CONFIG_F2FS_FAULT_INJECTION
-	if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH))
+	if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH)) {
+		f2fs_show_injection_info(FAULT_DIR_DEPTH);
 		return -ENOSPC;
+	}
 #endif
 	if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
 		return -ENOSPC;