From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ie0-f180.google.com (mail-ie0-f180.google.com [209.85.223.180]) by kanga.kvack.org (Postfix) with ESMTP id 15B986B0038 for ; Wed, 17 Dec 2014 10:36:17 -0500 (EST) Received: by mail-ie0-f180.google.com with SMTP id rp18so14681852iec.25 for ; Wed, 17 Dec 2014 07:36:16 -0800 (PST) Received: from resqmta-po-09v.sys.comcast.net (resqmta-po-09v.sys.comcast.net. [2001:558:fe16:19:96:114:154:168]) by mx.google.com with ESMTPS id ht1si11249615igb.26.2014.12.17.07.36.15 for (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Wed, 17 Dec 2014 07:36:15 -0800 (PST) Date: Wed, 17 Dec 2014 09:36:13 -0600 (CST) From: Christoph Lameter 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: owner-linux-mm@kvack.org List-ID: To: Joonsoo Kim Cc: Joonsoo Kim , akpm@linuxfoundation.org, Steven Rostedt , LKML , Thomas Gleixner , Linux Memory Management List , Pekka Enberg , Jesper Dangaard Brouer On Wed, 17 Dec 2014, Joonsoo Kim wrote: > Ping... and I found another way to remove preempt_disable/enable > without complex changes. > > What we want to ensure is getting tid and kmem_cache_cpu > on the same cpu. We can achieve that goal with below condition loop. > > I ran Jesper's benchmark and saw 3~5% win in a fast-path loop over > kmem_cache_alloc+free in CONFIG_PREEMPT. > > 14.5 ns -> 13.8 ns > > See following patch. Good idea. How does this affect the !CONFIG_PREEMPT case? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org