Re: [PATCH 0/2] /proc/stat: Reduce irqs counting performance overhead

From: Alexey Dobriyan
Date: Mon Jan 07 2019 - 18:49:09 EST

On Mon, Jan 07, 2019 at 05:41:28PM -0500, Daniel Colascione wrote:
> There should be a general-purpose way for /proc file readers to tell
> the kernel which bits of information interest them on a particular read
> syscall sequence or particular open(2) or something.

This opens a pandora box full of ioctls. /proc supports ioctls on files
which aren't /proc/$PID and /proc/sys/* though.

So people made a mess with allegedly easy text files and now they
continue to make even more mess adding ioctls on top.