From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756697AbdLOPA1 (ORCPT ); Fri, 15 Dec 2017 10:00:27 -0500 Received: from mga06.intel.com ([134.134.136.31]:14169 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752660AbdLOPAX (ORCPT ); Fri, 15 Dec 2017 10:00:23 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.45,405,1508828400"; d="scan'208";a="13803830" Date: Fri, 15 Dec 2017 17:00:20 +0200 From: Jarkko Sakkinen To: "Christopherson, Sean J" Cc: "linux-kernel@vger.kernel.org" , "intel-sgx-kernel-dev@lists.01.org" , "platform-driver-x86@vger.kernel.org" Subject: Re: [intel-sgx-kernel-dev] [PATCH v5 06/11] intel_sgx: driver for Intel Software Guard Extensions Message-ID: <20171215150020.e3vq5fh2rtydzhkt@linux.intel.com> References: <20171113194528.28557-1-jarkko.sakkinen@linux.intel.com> <20171113194528.28557-7-jarkko.sakkinen@linux.intel.com> <1510682106.3313.24.camel@intel.com> <20171114202835.64rl35asldh3jgui@linux.intel.com> <1510770027.11044.37.camel@intel.com> <37306EFA9975BE469F115FDE982C075BC6B3B5E6@ORSMSX108.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <37306EFA9975BE469F115FDE982C075BC6B3B5E6@ORSMSX108.amr.corp.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 13, 2017 at 11:18:29PM +0000, Christopherson, Sean J wrote: > Resurrecting this thread now that I have a system with launch control > and have been able to measure the performance impact... > > Regenerating the EINIT token every time adds somewhere in the vicinity > of ~5% overhead to creating an enclave, versus generating a token once > and reusing it in each EINIT call. This isn't a huge issue since real > world usage models likely won't be re-launching enclaves at a high rate, > but it is measurable. We can cache tokens in future in the kernel space, can't we? /Jarkko