Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751248AbdCOCrL (ORCPT ); Tue, 14 Mar 2017 22:47:11 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:38688 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750820AbdCOCrK (ORCPT ); Tue, 14 Mar 2017 22:47:10 -0400 Date: Wed, 15 Mar 2017 10:46:56 +0800 From: Greg KH To: Andi Kleen Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, Andi Kleen , peterz@infradead.org Subject: Re: [PATCH 4/7] kref: Remove WARN_ON for NULL release functions Message-ID: <20170315024656.GA11886@kroah.com> References: <20170315021431.13107-1-andi@firstfloor.org> <20170315021431.13107-5-andi@firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170315021431.13107-5-andi@firstfloor.org> User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 778 Lines: 19 On Tue, Mar 14, 2017 at 07:14:28PM -0700, Andi Kleen wrote: > From: Andi Kleen > > 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