From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7393EC4167B for ; Fri, 25 Nov 2022 09:03:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229718AbiKYJDY (ORCPT ); Fri, 25 Nov 2022 04:03:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50240 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229576AbiKYJDV (ORCPT ); Fri, 25 Nov 2022 04:03:21 -0500 Received: from formenos.hmeau.com (helcar.hmeau.com [216.24.177.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8548F31F98; Fri, 25 Nov 2022 01:03:18 -0800 (PST) Received: from loth.rohan.me.apana.org.au ([192.168.167.2]) by formenos.hmeau.com with smtp (Exim 4.94.2 #2 (Debian)) id 1oyUbu-000hD4-Kt; Fri, 25 Nov 2022 17:03:03 +0800 Received: by loth.rohan.me.apana.org.au (sSMTP sendmail emulation); Fri, 25 Nov 2022 17:03:02 +0800 Date: Fri, 25 Nov 2022 17:03:02 +0800 From: Herbert Xu To: Ard Biesheuvel Cc: "Jason A. Donenfeld" , Robert Elliott , davem@davemloft.net, tim.c.chen@linux.intel.com, ap420073@gmail.com, David.Laight@aculab.com, ebiggers@kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 10/24] crypto: x86/poly - limit FPU preemption Message-ID: References: <20221103042740.6556-1-elliott@hpe.com> <20221116041342.3841-1-elliott@hpe.com> <20221116041342.3841-11-elliott@hpe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 25, 2022 at 09:59:17AM +0100, Ard Biesheuvel wrote: > > On arm64, this is implemented in an assembler macro 'cond_yield' so we > don't need to preserve/restore the SIMD state state at all if the > yield is not going to result in a call to schedule(). For example, the > SHA3 code keeps 400 bytes of state in registers, which we don't want > to save and reload unless needed. (5f6cb2e617681 'crypto: > arm64/sha512-ce - simplify NEON yield') Yes this would be optimally done from the assembly code which would make a difference if they benefited from larger block sizes. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt