From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756057AbZKMKl5 (ORCPT ); Fri, 13 Nov 2009 05:41:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755778AbZKMKlv (ORCPT ); Fri, 13 Nov 2009 05:41:51 -0500 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:60332 "EHLO www.etchedpixels.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755683AbZKMKlv (ORCPT ); Fri, 13 Nov 2009 05:41:51 -0500 Date: Fri, 13 Nov 2009 10:43:38 +0000 From: Alan Cox To: Greg Steuck Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Steven Rostedt Subject: Re: RT wakeup woes in Linux 2.6.31.6 on Mac Mini Message-ID: <20091113104338.503e53d4@lxorguk.ukuu.org.uk> In-Reply-To: References: X-Mailer: Claws Mail 3.7.3 (GTK+ 2.14.7; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > trace.13653:kblockd/-65 1dN.. 132us+: blk_rq_map_sg <-scsi_init_sgtable > trace.13653:kblockd/-65 1dN.. 200us+: blk_rq_map_sg <-scsi_init_sgtable > trace.13653:kblockd/-65 1dN.. 264us+: ata_tf_to_fis <-ahci_qc_prep > trace.13653:kblockd/-65 1dN.. 289us+: blk_rq_map_sg <-scsi_init_sgtable > trace.13653:kblockd/-65 1dN.. 349us+: ata_tf_to_fis <-ahci_qc_prep Something very weird with your tracing there ata_tf_to_fis simply moves 20 bytes of memory about. It could be you are hitting some kind of caching effect with the AHCI controller I guess. Certainly looks odd of itself. > ... > trace.6039: pdflush-5162 1d.s. 0us : 5162:120:R + [001] > 6040: 0:S rxtest > trace.6039: pdflush-5162 1dN.. 61us+: idle_cpu <-irq_exit > trace.6039: pdflush-5162 1dN.. 130us!: idle_cpu <-irq_exit > trace.6039: pdflush-5162 1dN.. 273us!: idle_cpu <-irq_exit What power management do you have enabled ?