Hi Andrew,
Sorry for the long delay. :(
On 2023/1/13 6:43, Andrew Morton wrote:
On Thu, 12 Jan 2023 11:27:20 +0800 Chao Yu <chao@xxxxxxxxxx> wrote:
proc_notify_change() has updated i_uid, i_gid and i_mode into proc
dirent, we don't need to call mark_inode_dirty() for later writeback,
remove it.
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -127,7 +127,6 @@ static int proc_notify_change(struct user_namespace *mnt_userns,
return error;
setattr_copy(&init_user_ns, inode, iattr);
- mark_inode_dirty(inode);
proc_set_user(de, inode->i_uid, inode->i_gid);
de->mode = inode->i_mode;
procfs call mark_inode_dirty() in three places.
Correct.
Does mark_inode_dirty() of a procfs file actually serve any purpose?
I don't see any particular reason that procfs inode needs to be set dirty,
as an in-memory filesystem, there is no backing device, so all attributes
should have been updated into procfs dirent directly in .setattr().
In fact, also procfs doesn't implement .dirty_inode, .write_inode or
.writepage{,s} interfaces which serves delayed inode update, pages writeback
after inode is set as dirty.
Thanks,
