lkml.org 
[lkml]   [2023]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] proc: remove mark_inode_dirty() in proc_notify_change()
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@kernel.org> 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,

\
 
 \ /
  Last update: 2023-03-27 00:01    [W:0.111 / U:0.624 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site