Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751379AbaLQToZ (ORCPT ); Wed, 17 Dec 2014 14:44:25 -0500 Received: from resqmta-po-09v.sys.comcast.net ([96.114.154.168]:41334 "EHLO resqmta-po-09v.sys.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750885AbaLQToY (ORCPT ); Wed, 17 Dec 2014 14:44:24 -0500 Date: Wed, 17 Dec 2014 13:44:21 -0600 (CST) From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Joonsoo Kim cc: Joonsoo Kim , akpm@linuxfoundation.org, Steven Rostedt , LKML , Thomas Gleixner , Linux Memory Management List , Pekka Enberg , Jesper Dangaard Brouer Subject: Re: [PATCH 0/7] slub: Fastpath optimization (especially for RT) V1 In-Reply-To: Message-ID: References: <20141210163017.092096069@linux.com> <20141215075933.GD4898@js1304-P5Q-DELUXE> Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 17 Dec 2014, Christoph Lameter wrote: > On Wed, 17 Dec 2014, Joonsoo Kim wrote: > > > + do { > > + tid = this_cpu_read(s->cpu_slab->tid); > > + c = this_cpu_ptr(s->cpu_slab); > > + } while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid)); Here is another one without debugging: 0xffffffff811d23bb <+59>: mov %gs:0x8(%r9),%rdx tid(rdx) = this_cpu_read() 0xffffffff811d23c0 <+64>: mov %r9,%r8 0xffffffff811d23c3 <+67>: add %gs:0x7ee37d9d(%rip),%r8 c (r8) = 0xffffffff811d23cb <+75>: cmp 0x8(%r8),%rdx c->tid == tid 0xffffffff811d23cf <+79>: jne 0xffffffff811d23bb Actually that looks ok. -- 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/