On Sun, 5 May 2024 at 13:02, David Laight wrote:
>
> How much is the extra pair of atomics going to hurt performance?
> IIRC a lot of work was done to (try to) make epoll lockless.
If this makes people walk away from epoll, that would be absolutely
*lovely*. Maybe they'd start using io_uring
From: Linus Torvalds
> Sent: 05 May 2024 18:56
>
> epoll can call out to vfs_poll() with a file pointer that may race with
> the last 'fput()'. That would make f_count go down to zero, and while
> the ep->mtx locking means that the resulting file pointer tear-down will
> be blocked until the poll
On 5/5/24 11:55 AM, Linus Torvalds wrote:
> epoll can call out to vfs_poll() with a file pointer that may race with
> the last 'fput()'. That would make f_count go down to zero, and while
> the ep->mtx locking means that the resulting file pointer tear-down will
> be blocked until the poll
epoll can call out to vfs_poll() with a file pointer that may race with
the last 'fput()'. That would make f_count go down to zero, and while
the ep->mtx locking means that the resulting file pointer tear-down will
be blocked until the poll returns, it means that f_count is already
dead, and any