From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qg0-f45.google.com (mail-qg0-f45.google.com [209.85.192.45]) by kanga.kvack.org (Postfix) with ESMTP id 8188B6B0253 for ; Mon, 15 Feb 2016 13:44:30 -0500 (EST) Received: by mail-qg0-f45.google.com with SMTP id y9so117619562qgd.3 for ; Mon, 15 Feb 2016 10:44:30 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id v43si2441404qge.70.2016.02.15.10.44.29 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 15 Feb 2016 10:44:29 -0800 (PST) From: Laura Abbott Subject: [PATCHv2 0/4] Improve performance for SLAB_POISON Date: Mon, 15 Feb 2016 10:44:20 -0800 Message-Id: <1455561864-4217-1-git-send-email-labbott@fedoraproject.org> Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton Cc: Laura Abbott , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com, Kees Cook Hi, This is a follow up to my previous series (http://lkml.kernel.org/g/<1453770913-32287-1-git-send-email-labbott@fedoraproject.org>) This series takes the suggestion of Christoph Lameter and only focuses on optimizing the slow path where the debug processing runs. The two main optimizations in this series are letting the consistency checks be skipped and relaxing the cmpxchg restrictions when we are not doing consistency checks. With hackbench -g 20 -l 1000 averaged over 100 runs: Before slub_debug=P mean 15.607 variance .086 stdev .294 After slub_debug=P mean 10.836 variance .155 stdev .394 This still isn't as fast as what is in grsecurity unfortunately so there's still work to be done. Profiling ___slab_alloc shows that 25-50% of time is spent in deactivate_slab. I haven't looked too closely to see if this is something that can be optimized. My plan for now is to focus on getting all of this merged (if appropriate) before digging in to another task. As always feedback is appreciated. Laura Abbott (4): slub: Drop lock at the end of free_debug_processing slub: Fix/clean free_debug_processing return paths sl[aob]: Convert SLAB_DEBUG_FREE to SLAB_CONSISTENCY_CHECKS slub: Relax CMPXCHG consistency restrictions Documentation/vm/slub.txt | 4 +- include/linux/slab.h | 2 +- mm/slab.h | 5 +- mm/slub.c | 126 ++++++++++++++++++++++++++++------------------ tools/vm/slabinfo.c | 2 +- 5 files changed, 83 insertions(+), 56 deletions(-) -- 2.5.0 -- 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