Re: [PATCH AUTOSEL 5.5 542/542] pipe: use exclusive waits when reading or writing

18 Feb 2020


      On Tue, Feb 18, 2020 at 10:17:30AM -0800, Linus Torvalds wrote:
...
@@ -722,9 +722,10 @@ pipe_release(struct inode *inode, struct file *file)
   if (file->f_mode & FMODE_WRITE)
   	pipe->writers--;

if (pipe->readers || pipe->writers) {
wake_up_interruptible_sync_poll(&pipe->rd_wait, EPOLLIN | EPOLLRDNORM | EPOLLERR | EPOLLHUP);


wake_up_interruptible_sync_poll(&pipe->wr_wait, EPOLLOUT | EPOLLWRNORM | EPOLLERR | EPOLLHUP);




/* Was that the last reader or writer, but not the other side? */
if (!pipe->readers != !pipe->writers) {
wake_up_interruptible_all(&pipe->rd_wait);


wake_up_interruptible_all(&pipe->wr_wait);

kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
}

@@ -1026,8 +1027,8 @@ static int wait_for_partner(struct pipe_inode_info *pipe, unsigned int *cnt)
 
 static void wake_up_partner(struct pipe_inode_info *pipe)
 {

wake_up_interruptible(&pipe->rd_wait);
wake_up_interruptible(&pipe->wr_wait);


wake_up_interruptible_all(&pipe->rd_wait);
wake_up_interruptible_all(&pipe->wr_wait);

}
You don't want to move wake_up_partner() up and call it from pipe_release()?

    