From: "Huang, Ying" Subject: Re: [PATCH -mm crypto] AES: x86_64 asm implementation optimization Date: Wed, 16 Apr 2008 16:19:09 +0800 Message-ID: <1208333949.4322.5.camel@caritas-dev.intel.com> References: <1207723262.18313.37.camel@caritas-dev.intel.com> <20080416073108.GA13494@Chamillionaire.breakpoint.cc> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Herbert Xu , "Adam J. Richter" , Alexander Kjeldaas , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, mingo@elte.hu, tglx@linutronix.de To: Sebastian Siewior Return-path: Received: from mga02.intel.com ([134.134.136.20]:55929 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753353AbYDPIPA (ORCPT ); Wed, 16 Apr 2008 04:15:00 -0400 In-Reply-To: <20080416073108.GA13494@Chamillionaire.breakpoint.cc> Sender: linux-crypto-owner@vger.kernel.org List-ID: On Wed, 2008-04-16 at 09:31 +0200, Sebastian Siewior wrote: > * Huang, Ying | 2008-04-09 14:41:02 [+0800]: > > >This patch increases the performance of AES x86-64 implementation. The > >average increment is more than 6.3% and the max increment is > >more than 10.2% on Intel CORE 2 CPU. The performance increment is > >gained via the following methods: > > > >- Two additional temporary registers are used to hold the subset of > > the state, so that the dependency between instructions is reduced. > > > >- The expanded key is loaded via 2 64bit load instead of 4 32-bit load. > > > > From your description I would assume that the performance can only > increase. However, on my > |model name : AMD Athlon(tm) 64 Processor 3200+ > the opposite is the case [1], [2]. I dunno why and I didn't mixup > patched & unpached :). I checked this patch on En. I have no AMD machine. So I have not tested the patch on it. Maybe there are some pipeline or load/store unit difference between Intel and AMD CPUs. Tomorrow I can split the patch into a set of small patches, with one patch for one small step. Can you help me to test these patches to find out the reason for degradation on AMD CPU. > |model name : Intel(R) Core(TM)2 CPU T7200 @ 2.00GHz > and the performance really increases [3], [4]. > > [1] http://download.breakpoint.cc/aes_patch/patched.txt > [2] http://download.breakpoint.cc/aes_patch/unpatched.txt > [3] http://download.breakpoint.cc/aes_patch/perf_patched.txt > [4] http://download.breakpoint.cc/aes_patch/perf_originall.txt > > >--- > > arch/x86/crypto/aes-x86_64-asm_64.S | 101 ++++++++++++++++++++---------------- > > include/crypto/aes.h | 1 > > 2 files changed, 58 insertions(+), 44 deletions(-) > > > >--- a/include/crypto/aes.h > >+++ b/include/crypto/aes.h > >@@ -19,6 +19,7 @@ > > > > struct crypto_aes_ctx { > > u32 key_length; > >+ u32 _pad1; > > Why is this pad required? Do you want special alignment of the keys? Because the key is loaded in 64bit in this patch, I want to align the key with 64bit address. > > u32 key_enc[AES_MAX_KEYLENGTH_U32]; > > u32 key_dec[AES_MAX_KEYLENGTH_U32]; > > }; > > Best Regards, Huang Ying