From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id 830B4B7136 for ; Mon, 15 Jun 2009 12:44:53 +1000 (EST) Received: from sj-iport-1.cisco.com (sj-iport-1.cisco.com [171.71.176.70]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "sj-iport-1.cisco.com", Issuer "Cisco SSCA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id DBF6BDDD1B for ; Mon, 15 Jun 2009 12:44:52 +1000 (EST) From: Roland Dreier To: Avi Kivity Subject: Re: [PATCH 1/2] lib: Provide generic atomic64_t implementation References: <18995.20685.227683.561827@cargo.ozlabs.ibm.com> <4A34E4A5.3040306@redhat.com> <18996.60235.178618.531664@cargo.ozlabs.ibm.com> <4A34F564.2010500@redhat.com> Date: Sun, 14 Jun 2009 19:44:45 -0700 In-Reply-To: <4A34F564.2010500@redhat.com> (Avi Kivity's message of "Sun, 14 Jun 2009 16:04:36 +0300") Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Paul Mackerras , akpm@linux-foundation.org, Linus Torvalds List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > The new Nehalems provide 8 logical threads in a single socket. All > those threads share a cache, and they have cmpxchg8b anyway, so this > won't matter. FWIW, Nehalem EX actually goes to 8 cores/16 threads per socket. But worrying about 32-bit performance on Nehalem is a little silly -- this simplest solution is simply to run a 64-bit kernel. - R. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754289AbZFOCow (ORCPT ); Sun, 14 Jun 2009 22:44:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751562AbZFOCoo (ORCPT ); Sun, 14 Jun 2009 22:44:44 -0400 Received: from sj-iport-1.cisco.com ([171.71.176.70]:26928 "EHLO sj-iport-1.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751474AbZFOCoo (ORCPT ); Sun, 14 Jun 2009 22:44:44 -0400 X-IronPort-AV: E=Sophos;i="4.42,220,1243814400"; d="scan'208";a="199844917" From: Roland Dreier To: Avi Kivity Cc: Paul Mackerras , Linus Torvalds , benh@kernel.crashing.org, akpm@linux-foundation.org, linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] lib: Provide generic atomic64_t implementation References: <18995.20685.227683.561827@cargo.ozlabs.ibm.com> <4A34E4A5.3040306@redhat.com> <18996.60235.178618.531664@cargo.ozlabs.ibm.com> <4A34F564.2010500@redhat.com> X-Message-Flag: Warning: May contain useful information Date: Sun, 14 Jun 2009 19:44:45 -0700 In-Reply-To: <4A34F564.2010500@redhat.com> (Avi Kivity's message of "Sun, 14 Jun 2009 16:04:36 +0300") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.0.91 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-OriginalArrivalTime: 15 Jun 2009 02:44:46.0427 (UTC) FILETIME=[3E950AB0:01C9ED63] Authentication-Results: sj-dkim-3; header.From=rdreier@cisco.com; dkim=pass ( sig from cisco.com/sjdkim3002 verified; ); Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > The new Nehalems provide 8 logical threads in a single socket. All > those threads share a cache, and they have cmpxchg8b anyway, so this > won't matter. FWIW, Nehalem EX actually goes to 8 cores/16 threads per socket. But worrying about 32-bit performance on Nehalem is a little silly -- this simplest solution is simply to run a 64-bit kernel. - R.