Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422674Ab2JaLWF (ORCPT ); Wed, 31 Oct 2012 07:22:05 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:44562 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935399Ab2JaLWB (ORCPT ); Wed, 31 Oct 2012 07:22:01 -0400 Message-ID: <509109D2.9030209@gmail.com> Date: Wed, 31 Oct 2012 19:21:54 +0800 From: Shan Wei User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:16.0) Gecko/20121026 Thunderbird/16.0.2 MIME-Version: 1.0 To: cl@linux-foundation.org, David Miller , NetDev , Kernel-Maillist Subject: [PATCH 0/9] use this_cpu_ptr instead of per_cpu_ptr(p, smp_processor_id()) Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1715 Lines: 38 this_cpu_ptr is faster than per_cpu_ptr(p, smp_processor_id()). The latter helper needs to find the offset for current cpu, and needs more assembler instructions which objdump shows in following. per_cpu_ptr(p, smp_processor_id())： 1e: 65 8b 04 25 00 00 00 00 mov %gs:0x0,%eax 26: 48 98 cltq 28: 31 f6 xor %esi,%esi 2a: 48 c7 c7 00 00 00 00 mov $0x0,%rdi 31: 48 8b 04 c5 00 00 00 00 mov 0x0(,%rax,8),%rax 39: c7 44 10 04 14 00 00 00 movl $0x14,0x4(%rax,%rdx,1) this_cpu_ptr(p) 1e: 65 48 03 14 25 00 00 00 00 add %gs:0x0,%rdx 27: 31 f6 xor %esi,%esi 29: c7 42 04 14 00 00 00 movl $0x14,0x4(%rdx) 30: 48 c7 c7 00 00 00 00 mov $0x0,%rdi $ git diff --stat a932657f51eadb8280166e82dc7034dfbff3985a.. drivers/clocksource/arm_generic.c | 2 +- include/trace/ftrace.h | 4 +--- kernel/padata.c | 2 +- kernel/rcutree.c | 2 +- kernel/trace/blktrace.c | 2 +- kernel/trace/trace.c | 2 +- net/core/flow.c | 4 +--- net/openvswitch/datapath.c | 4 ++-- net/openvswitch/vport.c | 5 ++--- net/rds/ib_recv.c | 2 +- net/xfrm/xfrm_ipcomp.c | 7 +++---- 11 files changed, 15 insertions(+), 21 deletions(-) -- 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/