From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750951AbVHULZK (ORCPT ); Sun, 21 Aug 2005 07:25:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750957AbVHULZK (ORCPT ); Sun, 21 Aug 2005 07:25:10 -0400 Received: from smtp207.mail.sc5.yahoo.com ([216.136.129.97]:17821 "HELO smtp207.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S1750951AbVHULZI (ORCPT ); Sun, 21 Aug 2005 07:25:08 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=Bw8sUcS63ns6OQ8GfhsfRxweDX+7brpDDS1QxiaVGtduz6Gt6BBlfvTt0LRzSlrO4cyWyWBX7ZO6PyULNm2YnSaQ4ONrYWMzIwBI95rMJO4tr/dHD9PG88C7NzgUDuu3s9uxrxHdtovUVPaWvpxTsipUG6VhyhsiJIXIKIEDukk= ; Message-ID: <4308649D.7060008@yahoo.com.au> Date: Sun, 21 Aug 2005 21:25:17 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Debian/1.7.8-1 X-Accept-Language: en MIME-Version: 1.0 To: Andrew Morton CC: tony.luck@intel.com, linux-kernel@vger.kernel.org, jasonuhl@sgi.com Subject: Re: CONFIG_PRINTK_TIME woes References: <20050821021322.3986dd4a.akpm@osdl.org> <20050821021616.6bbf2a14.akpm@osdl.org> <430848F5.3040308@yahoo.com.au> <20050821023249.0e143030.akpm@osdl.org> In-Reply-To: <20050821023249.0e143030.akpm@osdl.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: > > yup. > > >>Why not use something like do_gettimeofday? (or I'm sure one >>of our time keepers can suggest the right thing to use). > > > do_gettimeofday() takes locks, so a) we can't do printk from inside it and Dang, yeah maybe this is the showstopper. > b) if you do a printk-from-interupt and the interrupted code was running > do_gettimeofday(), deadlock. > What about just using jiffies, then? Really, sched_clock() is very broken for this (I know you're not arguing against that). It can go backwards when called twice from the same CPU, and the number returned by one CPU need have no correlation with that returned by another. However, I understand you probably just want something quick and dirty for 2.6.13 and would be happy just if it isn't more broken than before ;) -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com