Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754332Ab0FYJag (ORCPT ); Fri, 25 Jun 2010 05:30:36 -0400 Received: from mga11.intel.com ([192.55.52.93]:35988 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751662Ab0FYJaf (ORCPT ); Fri, 25 Jun 2010 05:30:35 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.53,480,1272870000"; d="scan'208";a="811542987" Subject: Re: [RFC][PATCH] irq_work From: Huang Ying To: Frederic Weisbecker Cc: Peter Zijlstra , Ingo Molnar , "H.PeterA" <"nvin hpa"@zytor.com>, "linux-kernel@vger.kernel.org" , Andi Kleen In-Reply-To: References: <1277348698-17311-1-git-send-email-ying.huang@intel.com> <1277361352.1875.838.camel@laptop> <1277431963.3947.140.camel@yhuang-dev.sh.intel.com> <1277452110.22715.2116.camel@twins> <1277457439.3947.184.camel@yhuang-dev.sh.intel.com> Content-Type: text/plain; charset="UTF-8" Date: Fri, 25 Jun 2010 17:30:32 +0800 Message-ID: <1277458232.3947.186.camel@yhuang-dev.sh.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.30.1.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1504 Lines: 46 On Fri, 2010-06-25 at 17:23 +0800, Frederic Weisbecker wrote: > 2010/6/25 Huang Ying : > > On Fri, 2010-06-25 at 15:48 +0800, Peter Zijlstra wrote: > >> On Fri, 2010-06-25 at 10:12 +0800, Huang Ying wrote: > >> > > >> > It is better to add "void *data" field in this struct to allow same > >> > function can be used for multiple struct irq_work. > >> > >> No, simply do: > >> > >> struct my_foo { > >> struct irq_work work; > >> /* my extra data */ > >> } > >> > >> void my_func(struct irq_work *work) > >> { > >> struct my_foo *foo = container_of(work, struct my_foo, work); > >> > >> /* tada! */ > >> } > > > > Yes. This works too. But Adding "void *data" field is helpful if you do > > not embed struct irq_work into another struct. > > > That's what makes most sense. If you use work->data to put foo, then > you can also do the opposite. Now the best is to pick the choice that > gives you a real type and a typechecking, and not an error-prone and > obfuscated void * > > This is the way things are made in the kernel. struct work_struct, struct list, > struct rcu_head, etc... are all embedded into a container, so that we can > use container_of. container_of has no full type checking too. Best Regards, Huang Ying -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/