Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754832AbZI3WFp (ORCPT ); Wed, 30 Sep 2009 18:05:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754099AbZI3WFn (ORCPT ); Wed, 30 Sep 2009 18:05:43 -0400 Received: from mga02.intel.com ([134.134.136.20]:60117 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754361AbZI3WFm convert rfc822-to-8bit (ORCPT ); Wed, 30 Sep 2009 18:05:42 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.44,482,1249282800"; d="scan'208";a="555530520" From: "Luck, Tony" To: Christoph Lameter CC: Tejun Heo , Nick Piggin , "Yu, Fenghua" , linux-ia64 , Ingo Molnar , Rusty Russell , "linux-kernel@vger.kernel.org" Date: Wed, 30 Sep 2009 15:05:43 -0700 Subject: RE: [PATCHSET percpu#for-next] percpu: convert ia64 to dynamic percpu and drop the old one, take#2 Thread-Topic: [PATCHSET percpu#for-next] percpu: convert ia64 to dynamic percpu and drop the old one, take#2 Thread-Index: AcpCD+et5X0AeNm2RLa4hdwXyo2iqwACTD8w Message-ID: <57C9024A16AD2D4C97DC78E552063EA3E2F03FDC@orsmsx505.amr.corp.intel.com> References: <1253682382-24740-1-git-send-email-tj@kernel.org> <4AC153EA.2050007@suse.de> <57C9024A16AD2D4C97DC78E552063EA3E2F03E58@orsmsx505.amr.corp.intel.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 758 Lines: 18 > Tony: Could we use a global register for the per cpu address? That would > make IA64 work similar to sparc. Would that be a useful trade of resources for convenience? We've already hard-wired r13 for "current". Grabbing another one would require fixing (since user code will have clobbered it). Possibly re-working any existing code that already uses whatever register you choose. How would that compare with using [r13]? We might have a krN free ... but kregs are a lot slower than real registers. -Tony -- 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/