From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761786AbcIWTXj (ORCPT ); Fri, 23 Sep 2016 15:23:39 -0400 Received: from mail-yw0-f193.google.com ([209.85.161.193]:35185 "EHLO mail-yw0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752259AbcIWTXg (ORCPT ); Fri, 23 Sep 2016 15:23:36 -0400 Date: Fri, 23 Sep 2016 15:23:34 -0400 From: Tejun Heo To: zijun_hu Cc: Andrew Morton , zijun_hu@htc.com, linux-mm@kvack.org, "linux-kernel@vger.kernel.org" , cl@linux.com Subject: Re: [PATCH 1/1] mm/percpu.c: simplify grouping cpu logic in pcpu_build_alloc_info() Message-ID: <20160923192334.GD31387@htj.duckdns.org> References: <5dcf5870-67ad-97e4-518b-645d60b0a520@zoho.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5dcf5870-67ad-97e4-518b-645d60b0a520@zoho.com> User-Agent: Mutt/1.7.0 (2016-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 24, 2016 at 02:15:09AM +0800, zijun_hu wrote: > From: zijun_hu > > simplify grouping cpu logic in pcpu_build_alloc_info() to improve > readability and performance, it discards the goto statement too > > for every possible cpu, decide whether it can share group id of any > lower index CPU, use the group id if so, otherwise a new group id > is allocated to it > > Signed-off-by: zijun_hu I'm not gonna change that code unless there are clear upsides. It's a complicated code path which is run once during boot. It's not worth optimizing, the author doesn't explain how the change has been tested or verified and doesn't respond to people pointing out that these drive-by patches aren't helpful. I won't engage with his patches until he changes his approach and think that it's advisable for others to do so too. Nacked-by: Tejun Heo Thanks. -- tejun