Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753854Ab3ILOWr (ORCPT ); Thu, 12 Sep 2013 10:22:47 -0400 Received: from a9-99.smtp-out.amazonses.com ([54.240.9.99]:60633 "EHLO a9-99.smtp-out.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753470Ab3ILOWo (ORCPT ); Thu, 12 Sep 2013 10:22:44 -0400 Date: Thu, 12 Sep 2013 14:22:43 +0000 From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Frederic Weisbecker cc: Andrew Morton , Gilad Ben-Yossef , Thomas Gleixner , Mike Frysinger , linux-kernel@vger.kernel.org, "Paul E. McKenney" Subject: Re: [RFC] Restrict kernel spawning of threads to a specified set of cpus. In-Reply-To: <20130912141625.GA23357@somewhere> Message-ID: <00000141128d759a-44dcacb6-8f48-4f9b-8381-d14003bd6da1-000000@email.amazonses.com> References: <00000140efbcb701-c26320b3-f434-4538-bc80-8e92fed6f303-000000@email.amazonses.com> <20130911220228.GB15367@somewhere> <000001411282afa6-fe9c0543-0447-492b-991e-dc8214884b88-000000@email.amazonses.com> <20130912141625.GA23357@somewhere> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SES-Outgoing: 2013.09.12-54.240.9.99 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 790 Lines: 22 On Thu, 12 Sep 2013, Frederic Weisbecker wrote: > On Thu, Sep 12, 2013 at 02:10:56PM +0000, Christoph Lameter wrote: > > On Thu, 12 Sep 2013, Frederic Weisbecker wrote: > > > > > Why not do this from userspace instead? > > > > Because the cpumasks are hardcoded in the kernel code. > > > > Ok but you can change the affinity of a kthread from userspace, as > long as you define a cpu set that is among that kthread's cpus allowed. Ok but at that point kthread has already spawned a lot of kernel threads. The same is true for init and kmod. -- 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/