Re: [PATCH 4/7] kref: Remove WARN_ON for NULL release functions

From: Greg KH
Date: Tue Mar 14 2017 - 22:47:21 EST


On Tue, Mar 14, 2017 at 07:14:28PM -0700, Andi Kleen wrote:
> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>
> The kref functions check for NULL release functions.
> This WARN_ON seems rather pointless. We will eventually release and
> then just crash nicely. It is also somewhat expensive because
> these functions are inlined in a lot of places.
> Removing the WARN_ONs saves around 2.3k in this kernel
> (likely more in others with more drivers)
>
> text data bss dec hex filename
> 9083992 5367600 11116544 25568136 1862388 vmlinux-before-load-avg
> 9070166 5367600 11116544 25554310 185ed86 vmlinux-load-avg

WARN_ON() is heavy, didn't realize that.

No objection from me.

Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>