Return-path: Received: from mail.w1.fi ([212.71.239.96]:54776 "EHLO li674-96.members.linode.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750868AbaGaUF0 (ORCPT ); Thu, 31 Jul 2014 16:05:26 -0400 Date: Thu, 31 Jul 2014 23:05:22 +0300 From: Jouni Malinen To: Christian Lamparter Cc: Ben Greear , "linux-wireless@vger.kernel.org" , Johannes Berg Subject: Re: Looking for non-NIC hardware-offload for wpa2 decrypt. Message-ID: <20140731200522.GA8868@w1.fi> (sfid-20140731_220529_563376_1EB03CEC) References: <5338F1B8.5040305@candelatech.com> <3302077.5sUEMiqNRr@debian64> <53D82540.5060403@candelatech.com> <2968058.2zJHmYrLUV@debian64> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <2968058.2zJHmYrLUV@debian64> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, Jul 30, 2014 at 08:59:33PM +0200, Christian Lamparter wrote: > If you have disabled rx-decrypt logic of ath10k, then why isn't _aesni_dec1 > or aes_decrypt listed in the perf top result? I think they should be. Have you > removed them from the "perf top results" or are they really absent > altogether? > > Because, from this perf result, it looks like your CPU is not burden by the > incoming RX at all?! Instead it is busy with the encryption of frames > it will be transmitting (in case of tcp, this could be tcp acks). Keep in mind that this is CCMP, i.e., AES in CCM (Counter with CBC-MAC) mode. The CCM mode uses only the block cipher encryption function, i.e., you won't be seeing aes_decrypt or _aesni_dec1 for this even on the RX path (AES encryption operations are used to generate the key stream blocks for CCM decryption). -- Jouni Malinen PGP id EFC895FA