From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [RFC PATCH v2 1/4] cpuidle: (powerpc) Add cpu_idle_wait() to allow switching of idle routines Date: Tue, 29 Nov 2011 18:01:55 +1100 Message-ID: <1322550115.23348.72.camel@pasglop> References: <20111117112815.9191.2322.stgit@localhost6.localdomain6> <20111117112830.9191.1951.stgit@localhost6.localdomain6> <1322434096.23348.6.camel@pasglop> <4ED36A37.3030409@linux.vnet.ibm.com> <1322512522.23348.43.camel@pasglop> <4ED47EC2.2090802@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4ED47EC2.2090802@linux.vnet.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Deepthi Dharwar Cc: linuxppc-dev@ozlabs.org, linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org List-Id: linux-pm@vger.kernel.org On Tue, 2011-11-29 at 12:12 +0530, Deepthi Dharwar wrote: > > Yes, this could be problematic as there is small window for the > race condition to occur . Otherwise we need to manually schedule > it by running a kernel thread but this would definitely have a > overhead and would be an overkill. Depends what this "window" is. IE. What are you trying to protect yourself against ? What's the risk ? If it's just module unload, then stop_machine is probably your friend :-) Cheers, Ben.