From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 3F7BD67C6B for ; Thu, 23 Nov 2006 22:01:06 +1100 (EST) Subject: Re: NTP time sync From: Benjamin Herrenschmidt To: Andi Kleen In-Reply-To: <20061123105400.GA75714@muc.de> References: <20061122203633.611acaa8@inspiron> <20061123105400.GA75714@muc.de> Content-Type: text/plain Date: Thu, 23 Nov 2006 22:00:05 +1100 Message-Id: <1164279605.5653.51.camel@localhost.localdomain> Mime-Version: 1.0 Cc: akpm@osdl.org, Alessandro Zummo , lethal@linux-sh.org, Linux Kernel Mailing List , ralf@linux-mips.org, David Brownell , linuxppc-dev@ozlabs.org, paulus@samba.org, rmk@arm.linux.org.uk, davem@davemloft.net, kkojima@rr.iij4u.or.jp List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2006-11-23 at 11:54 +0100, Andi Kleen wrote: > > [1] http://lkml.org/lkml/2006/3/28/358 > > What was the answer to Matt's last question in there? > If the existing user land does it already then > probably. If not then a good migration strategy would > be needed. Couldn't we have a transition period by making the kernel not rely on interrupts ? if the NTP irq code just triggers a work queue, then all of a sudden, all of the RTC drivers can be used and the latency is small. That might well be a good enough solution and is very simple. Ben