From patchwork Thu Mar 14 15:39:19 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Kosina X-Patchwork-Id: 227718 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id AD21F2C00B2 for ; Fri, 15 Mar 2013 02:39:24 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755698Ab3CNPjX (ORCPT ); Thu, 14 Mar 2013 11:39:23 -0400 Received: from cantor2.suse.de ([195.135.220.15]:47523 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751089Ab3CNPjW (ORCPT ); Thu, 14 Mar 2013 11:39:22 -0400 Received: from relay1.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 37820A51F7; Thu, 14 Mar 2013 16:39:21 +0100 (CET) Date: Thu, 14 Mar 2013 16:39:19 +0100 (CET) From: Jiri Kosina To: Alan Stern Cc: Peter Hurley , Thomas Meyer , Shawn Starr , Kernel development list , USB list , linux-acpi@vger.kernel.org, "Rafael J. Wysocki" , Bjorn Helgaas , linux-pci@vger.kernel.org Subject: Re: [3.9-rc1] irq 16: nobody cared (was [3.9-rc1] very poor interrupt responses) In-Reply-To: Message-ID: References: User-Agent: Alpine 2.00 (LNX 1167 2008-08-23) MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, 14 Mar 2013, Alan Stern wrote: > > > Can you try to do a git bisect for this? Is the sluggish system > > > response clear enough that you can tell reliably when it is present and > > > when it isn't? > > > > That was my first thought, but unfortunately I am afraid there will be > > point at which I will easily make a bisection mistake, as the > > responsiveness of the system varies over time, so it's not really a > > 100% objective measure. > > All right. > > There have been only three significant changes to uhci-hcd since last > summer, and two of them appear to be completely unrelated to this > issue. The three commits are > > 3171fcabb169 USB: uhci: beautify source code > 13996ca7afd5 USB: uhci: check buffer length to avoid memory > overflow > 0f815a0a700b USB: UHCI: fix IRQ race during initialization > > Reverting the first two almost certainly will not have any effect, but > you may as well try it anyway. The third commit may be relevant. I have reverted all three commits, and the "nobody cared" is still there. > If you revert all three and still see the problem then it must be > caused by changes outside of the USB stack. Differences in interrupt > routing could be a result of changes to PCI or ACPI. Have you compared > the current /proc/interrupts with versions from earlier kernels without > this problem? The diff of stripped-down (without CPU statistics) /proc/interrupts from some oldish working 3.1 and the current tree: IRQ16 is routed differently (usb4 vs usb6), so that might be relevant. > Is occurrence of the "nobody cared" connected with any particular > device? Somebody reported a similar problem not long ago (although IIRC > it was for OHCI rather than UHCI) which appeared to be related to > activity on the built-in webcam. Will check this. No external devices are plugged in, I think the only internal one it has is bluetooth chip. I'll try turning it off. --- /tmp/interrupts-old.txt 2013-03-14 16:30:46.938710286 +0100 +++ /tmp/interrupts-new.txt 2013-03-14 16:30:18.954571413 +0100 @@ -3,27 +3,28 @@ 8:IO-APIC-edge rtc0 9:IO-APIC-fasteoi acpi 12:IO-APIC-edge i8042 - 16:IO-APIC-fasteoi uhci_hcd:usb6 - 17:IO-APIC-fasteoi uhci_hcd:usb7 - 18:IO-APIC-fasteoi ata_generic, uhci_hcd:usb8 - 19:IO-APIC-fasteoi ehci_hcd:usb2 - 20:IO-APIC-fasteoi uhci_hcd:usb3 - 21:IO-APIC-fasteoi uhci_hcd:usb4 - 22:IO-APIC-fasteoi uhci_hcd:usb5 - 23:IO-APIC-fasteoi ehci_hcd:usb1 + 16:IO-APIC-fasteoi uhci_hcd:usb4 + 17:IO-APIC-fasteoi uhci_hcd:usb5 + 18:IO-APIC-fasteoi ata_generic, uhci_hcd:usb6 + 19:IO-APIC-fasteoi ehci_hcd:usb8 + 20:IO-APIC-fasteoi uhci_hcd:usb1 + 21:IO-APIC-fasteoi uhci_hcd:usb2 + 22:IO-APIC-fasteoi uhci_hcd:usb3 + 23:IO-APIC-fasteoi ehci_hcd:usb7, i801_smbus 40:PCI-MSI-edge PCIe PME 41:PCI-MSI-edge PCIe PME 42:PCI-MSI-edge PCIe PME 43:PCI-MSI-edge ahci 44:PCI-MSI-edge i915 45:PCI-MSI-edge eth0 - 46:PCI-MSI-edge iwlagn + 46:PCI-MSI-edge iwlwifi 47:PCI-MSI-edge snd_hda_intel NMI:Non-maskable interrupts LOC:Local timer interrupts SPU:Spurious interrupts PMI:Performance monitoring interrupts IWI:IRQ work interrupts +RTR:APIC ICR read retries RES:Rescheduling interrupts CAL:Function call interrupts TLB:TLB shootdowns