Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752983AbZIWOCI (ORCPT ); Wed, 23 Sep 2009 10:02:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752992AbZIWOCG (ORCPT ); Wed, 23 Sep 2009 10:02:06 -0400 Received: from hera.kernel.org ([140.211.167.34]:44143 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752935AbZIWOCF (ORCPT ); Wed, 23 Sep 2009 10:02:05 -0400 Message-ID: <4ABA2A3A.6020308@kernel.org> Date: Wed, 23 Sep 2009 23:01:30 +0900 From: Tejun Heo User-Agent: Thunderbird 2.0.0.22 (X11/20090605) MIME-Version: 1.0 To: Christoph Lameter CC: Nick Piggin , Tony Luck , Fenghua Yu , linux-ia64 , Ingo Molnar , Rusty Russell , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/4] ia64: allocate percpu area for cpu0 like percpu areas for other cpus References: <1253605214-23210-1-git-send-email-tj@kernel.org> <1253605214-23210-3-git-send-email-tj@kernel.org> <4AB983B6.6050203@kernel.org> In-Reply-To: X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Wed, 23 Sep 2009 14:01:32 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 872 Lines: 26 Hello, Christoph Lameter wrote: > You did not answer my question. Hmmm... > The local percpu variables are accessed via a static per cpu > virtual mapping. You cannot place per cpu variables outside of that > virtual address range of PERCPU_PAGE_SIZE. > > What happens if the percpu allocator allocates more data than available in > the reserved area? I still don't understand your question. Static percpu variables are always allocated from the first chunk inside that PERCPU_PAGE_SIZE area. Dynamic allocations can go outside of that but they don't need any special handling. What problems are you seeing? -- tejun -- 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/