Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261595AbUJXUDp (ORCPT ); Sun, 24 Oct 2004 16:03:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261594AbUJXUDp (ORCPT ); Sun, 24 Oct 2004 16:03:45 -0400 Received: from peabody.ximian.com ([130.57.169.10]:5596 "EHLO peabody.ximian.com") by vger.kernel.org with ESMTP id S261600AbUJXUBv (ORCPT ); Sun, 24 Oct 2004 16:01:51 -0400 Subject: Re: How is user space notified of CPU speed changes? From: Robert Love To: Lee Revell Cc: Alan Cox , Linux Kernel Mailing List In-Reply-To: <1098508238.13176.17.camel@krustophenia.net> References: <1098399709.4131.23.camel@krustophenia.net> <1098444170.19459.7.camel@localhost.localdomain> <1098508238.13176.17.camel@krustophenia.net> Content-Type: text/plain Date: Sun, 24 Oct 2004 16:02:12 -0400 Message-Id: <1098648132.5843.5.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.0.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 874 Lines: 24 On Sat, 2004-10-23 at 01:10 -0400, Lee Revell wrote: > OK, thanks. Still no answer to my original question though. > > JACK makes extensive use of microsecond-level timers. These must be > calibrated at startup, and recalibrated when the CPU speed changes. How > does JACK register with the kernel to be notified when the CPU speed > changes? Ignoring all of these meta-issues like whether or not JACK actually should be checking the CPU speed: Yes, I think that doing a kevent tied to the processor object when the speed changes is an absolutely ideal use of the kernel event layer. HAL would use it, too. Robert Love - 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/