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 647CF679A6 for ; Thu, 22 Jun 2006 16:02:18 +1000 (EST) Subject: Re: windfarm got signal From: Benjamin Herrenschmidt To: Johannes Berg In-Reply-To: <1150847482.16662.13.camel@johannes> References: <1150847482.16662.13.camel@johannes> Content-Type: text/plain Date: Thu, 22 Jun 2006 16:02:03 +1000 Message-Id: <1150956123.3633.23.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linuxppc-dev list , linux-pm List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2006-06-21 at 01:51 +0200, Johannes Berg wrote: > Hey, > > after cpu hotplug I decided to write some fake suspend routines for > ppc64 that always fail to see what all the drivers would say... The > first thing I saw was during the phase where all threads are stopped, > that windfarm got a signal! > > Shortly after that, the fans were revved up fully but I guess that's > expected if the wf control loop exits. > > So now I'm trying to see *why* it got a signal there. Any ideas? Is that > expected with pm and windfarm just does the wrong thing there by taking > the signal as a reason to exit the control thread? > > [code in question is windfarm_core.c:wf_thread_func] I think it's the way the freezer works ... it sends a pseudo signal to all kernel threads who are then supposed to do something like test for PF_FREEZE or something like that. Ben.