From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933221Ab1EYIoS (ORCPT ); Wed, 25 May 2011 04:44:18 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:59419 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932931Ab1EYIoQ (ORCPT ); Wed, 25 May 2011 04:44:16 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=qpkLGriVxceJSWf1jpurHPBwD6HzmteQVuIzXoo95Fxh2rJBO+GkfomDzvlL+vQXcE AW6dhYqxZtBOgrTcqQmcTndrbGnIoVBuUX8gCf6t2tHfpinrn84wtbxrFJ+sXAQOoXnf RkHt7qok0BYoP7Sci+wKsqRPDTxtbEXtSiMck= Date: Wed, 25 May 2011 10:44:11 +0200 From: Tejun Heo To: Linus Torvalds Cc: oleg@redhat.com, vda.linux@googlemail.com, jan.kratochvil@redhat.com, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, indan@nul.nu, bdonlan@gmail.com, pedro@codesourcery.com Subject: Re: [PATCH 07/19] ptrace: use bit_waitqueue for TRAPPING instead of wait_chldexit Message-ID: <20110525084411.GB10146@htj.dyndns.org> References: <1306262259-7285-1-git-send-email-tj@kernel.org> <1306262259-7285-8-git-send-email-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Linus. On Tue, May 24, 2011 at 12:03:16PM -0700, Linus Torvalds wrote: > #define JOBCTL_TRAPPING_BIT xxx > #define JOBCTL_TRAPPING (1u << JOBCTL_TRAPPING_BIT) > > but never ever do that stupid ilog2() thing. Every time I see it I go > "ok, that's just total crap". > > Don't do it. Sure, but can you at least explain why you dislike it so much? This is the only place bit position is needed and having two variants with _BIT can be confusing (I did that more than once with workqueue code). ilog2() could be, I don't know, unfamiliar, but what's so crappy about it? Thanks. -- tejun