Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756831Ab0KLKip (ORCPT ); Fri, 12 Nov 2010 05:38:45 -0500 Received: from eu1sys200aog109.obsmtp.com ([207.126.144.127]:53004 "EHLO eu1sys200aog109.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753832Ab0KLKio (ORCPT ); Fri, 12 Nov 2010 05:38:44 -0500 Message-ID: <4CDD18F9.5090005@stericsson.com> Date: Fri, 12 Nov 2010 11:37:45 +0100 From: Linus Walleij User-Agent: Thunderbird 2.0.0.24 (X11/20100411) MIME-Version: 1.0 To: Thomas Gleixner Cc: =?ISO-8859-1?Q?Uwe_Kleine-K=F6nig?= , john stultz , Rabin VINCENT , Nicolas Pitre , "linux-kernel@vger.kernel.org" , Colin Cross , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH] RFC: nomadik: expand timesource to 63 bits References: <1289466356-16697-1-git-send-email-linus.walleij@stericsson.com> <20101112095739.GH18358@pengutronix.de> <4CDD120A.2050401@stericsson.com> In-Reply-To: Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1201 Lines: 28 Thomas Gleixner wrote: > On Fri, 12 Nov 2010, Linus Walleij wrote: >> Uwe Kleine-K?nig wrote: >> >>> Instead of implementing sched_clock for each architecture seperatly, >>> wouldn't it be nice to have a generic sched_clock that uses the >>> architecture's clocksource? I tried to implement that some time ago, >>> but tglx shoot it down because of locking problems. >> I was and still am a big fan of this approach, I am willing to help >> testing it if you want to dust off this patch set... > > sched_clock is not necessarily the same as the current clocksource. IIRC Uwe:s approach was that if and only if you would want to use the clocksource for sched_clock() you provide a special flag on the clocksource, and it will be attempted to be used for sched_clock(). Incidentally the dual use of a single free-running timer as both single clocksource and sched_clock() baseline seem to creep up in a lot of embedded platforms... Yours, Linus Walleij -- 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/