Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753956AbYLILj4 (ORCPT ); Tue, 9 Dec 2008 06:39:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752289AbYLILjr (ORCPT ); Tue, 9 Dec 2008 06:39:47 -0500 Received: from mail.crca.org.au ([67.207.131.56]:55416 "EHLO crca.org.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752152AbYLILjq (ORCPT ); Tue, 9 Dec 2008 06:39:46 -0500 X-Bogosity: Ham, spamicity=0.000000 Subject: [PATCH] Firewire node manager causes up to ~3.25s delay in freezing tasks. From: Nigel Cunningham To: krh@redhat.com, stefanr@s5r6.in-berlin.de, linux1394-devel@lists.sourceforge.net, linux-pm , LKML Content-Type: text/plain Organization: Christian Reformed Churches of Australia Date: Tue, 09 Dec 2008 22:40:20 +1100 Message-Id: <1228822820.6681.22.camel@nigel-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2030 Lines: 48 Hi all. (Okay, having learnt that ieee1394 != bluetooth, I'll try again :>) The firewire nodemanager function "nodemgr_host_thread" contains a loop that calls try_to_freeze near the top of the loop, but then delays for up to 3.25 seconds (plus time to do work) before getting back to the top of the loop. When starting a cycle post-boot, this doesn't seem to bite, but it is causing a noticeable delay at boot time, when freezing processes prior to starting to read the image. The following patch adds invocation of try_to_freeze to the subloops that are used in the body of this function. With these additions, the time to freeze when starting to resume at boot time is virtually zero. I'm no expert on bluetooth, and so don't know that we shouldn't check the return value and jump back to the top of the loop or such like after being frozen, but I submit it for your consideration. Signed-off-by: Nigel Cunningham nodemgr.c | 2 ++ 1 file changed, 2 insertions(+) diff -ruNp 710-nodemanager-freezing.patch-old/drivers/ieee1394/nodemgr.c 710-nodemanager-freezing.patch-new/drivers/ieee1394/nodemgr.c --- 710-nodemanager-freezing.patch-old/drivers/ieee1394/nodemgr.c 2008-12-06 08:42:08.000000000 +1100 +++ 710-nodemanager-freezing.patch-new/drivers/ieee1394/nodemgr.c 2008-12-09 18:49:26.000000000 +1100 @@ -1685,6 +1685,7 @@ static int nodemgr_host_thread(void *dat g = get_hpsb_generation(host); for (i = 0; i < 4 ; i++) { msleep_interruptible(63); + try_to_freeze(); if (kthread_should_stop()) goto exit; @@ -1725,6 +1726,7 @@ static int nodemgr_host_thread(void *dat /* Sleep 3 seconds */ for (i = 3000/200; i; i--) { msleep_interruptible(200); + try_to_freeze(); if (kthread_should_stop()) goto exit; -- 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/