Re: [RFC v6 1/2] epoll: Implement eventpoll_replace_file()

[Matthew Wilcox]

On Tue, May 23, 2023 at 06:58:01AM +0000, aloktiagi wrote:
> +/*
> + * This is called from eventpoll_replace() to replace a linked file in the epoll
> + * interface with a new file received from another process. This is useful in
> + * cases where a process is trying to install a new file for an existing one
> + * that is linked in the epoll interface
> + */
> +int eventpoll_replace_file(struct file *toreplace, struct file *file, int tfd)

Functions do not control where they are called from.  Just take that
clause out:

/*
 * Replace a linked file in the epoll interface with a new file received
 * from another process. This allows a process to
 * install a new file for an existing one that is linked in the epoll
 * interface
 */

But, erm, aren't those two sentences basically saying the same thing?
So simplify again:

/*
 * Replace a linked file in the epoll interface with a new file
 */

> diff --git a/include/linux/eventpoll.h b/include/linux/eventpoll.h
> index 3337745d81bd..2a6c8f52f272 100644
> --- a/include/linux/eventpoll.h
> +++ b/include/linux/eventpoll.h
> @@ -25,6 +25,14 @@ struct file *get_epoll_tfile_raw_ptr(struct file *file, int tfd, unsigned long t
>  /* Used to release the epoll bits inside the "struct file" */
>  void eventpoll_release_file(struct file *file);
>  
> +/*
> + * This is called from fs/file.c:do_replace() to replace a linked file in the
> + * epoll interface with a new file received from another process. This is useful
> + * in cases where a process is trying to install a new file for an existing one
> + * that is linked in the epoll interface
> + */
> +int eventpoll_replace_file(struct file *toreplace, struct file *file, int tfd);

No need to repeat the comment again.  Just delete it here.