Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262212AbVDLWWa (ORCPT ); Tue, 12 Apr 2005 18:22:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262531AbVDLWTJ (ORCPT ); Tue, 12 Apr 2005 18:19:09 -0400 Received: from gateway-1237.mvista.com ([12.44.186.158]:2293 "EHLO av.mvista.com") by vger.kernel.org with ESMTP id S262212AbVDLWQL (ORCPT ); Tue, 12 Apr 2005 18:16:11 -0400 Subject: Re: FUSYN and RT From: Daniel Walker Reply-To: dwalker@mvista.com To: Esben Nielsen Cc: linux-kernel@vger.kernel.org, inaky.perez-gonzalez@intel.com, mingo@elte.hu In-Reply-To: References: Content-Type: text/plain Organization: MontaVista Message-Id: <1113344159.6394.25.camel@dhcp153.mvista.com> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.2 (1.2.2-4) Date: 12 Apr 2005 15:15:59 -0700 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1266 Lines: 29 On Tue, 2005-04-12 at 13:29, Esben Nielsen wrote: > You basicly need 3 priorities: > 1) Actual: task->prio > 2) Base prio with no RT locks taken: task->static_prio > 3) Base prio with no Fusyn locks taken: task->?? > > So no, you will not need the same API, at all :-) Fusyn manipulates > task->static_prio and only task->prio when no RT lock is taken. When the > first RT-lock is taken/released it manipulates task->prio only. A release > of a Fusyn will manipulate task->static_prio as well as task->prio. mutex_setprio() , I don't know if you could call that an API but that's what I was talking about.. They should both use that. I think it would be better if the RT mutex (and fusyn) didn't depend on a field in the task_struct to retain the old priority. That would make it easier .. This goes back to the assumption that the locking isn't intermingled once you get into the kernel . The RT mutex can safely save the owner priority with out a Fusyn jumping in and changing it and the other way around.. Daniel - 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/