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 X-Spam-Level: X-Spam-Status: No, score=-11.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DCA15C4361B for ; Fri, 11 Dec 2020 19:25:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 89D4D2405B for ; Fri, 11 Dec 2020 19:25:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2395333AbgLKRom (ORCPT ); Fri, 11 Dec 2020 12:44:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:57874 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2395330AbgLKRoj (ORCPT ); Fri, 11 Dec 2020 12:44:39 -0500 Date: Fri, 11 Dec 2020 09:43:57 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1607708639; bh=7nRRic/cUXS9Hr120HkaEBHl46oBlU5a4nWuOWcPCFM=; h=From:To:Cc:Subject:References:In-Reply-To:From; b=MEsY9jZz2eeaM+mnf1yXNs0NqEbEnR/tGlBxqTngG/GgPHKPMN2KGA1wIt0eILUXH LJWYJhD4xe8YcXtKtrL+/zHYaAFgHr9pE9ccJtQjBaotXOQKVhoCbN2n8tQQ8uSIhj xiecXbJf+DaemV3DdBQR74EYj7fRiyBQ3Pq0lqv59XZG3tjiwVPTd1m8MfPhiS971z xC9YAFxmFHFe6g2TmrYLNq38X2wZKnpm0XORAeI6OJDXKZpHbVu7RsYE7RoNwwUfct aJXCmwDhgqIEr40Hliycj8/QkthUgjnBY9GicG65BsHMwzJaKLU9GqgKm+Wrg/5ibd 75JgQIgXoVnOA== From: Eric Biggers To: Tony W Wang-oc Cc: herbert@gondor.apana.org.au, davem@davemloft.net, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, TimGuo-oc@zhaoxin.com, CooperYan@zhaoxin.com, QiyuanWang@zhaoxin.com, HerryYang@zhaoxin.com, CobeChen@zhaoxin.com, SilviaZhao@zhaoxin.com Subject: Re: [PATCH] crypto: x86/crc32c-intel - Don't match some Zhaoxin CPUs Message-ID: References: <1607686144-2604-1-git-send-email-TonyWWang-oc@zhaoxin.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1607686144-2604-1-git-send-email-TonyWWang-oc@zhaoxin.com> Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Fri, Dec 11, 2020 at 07:29:04PM +0800, Tony W Wang-oc wrote: > The driver crc32c-intel match CPUs supporting X86_FEATURE_XMM4_2. > On platforms with Zhaoxin CPUs supporting this X86 feature, When > crc32c-intel and crc32c-generic are both registered, system will > use crc32c-intel because its .cra_priority is greater than > crc32c-generic. This case expect to use crc32c-generic driver for > some Zhaoxin CPUs to get performance gain, So remove these Zhaoxin > CPUs support from crc32c-intel. > > Signed-off-by: Tony W Wang-oc Does this mean that the performance of the crc32c instruction on those CPUs is actually slower than a regular C implementation? That's very weird. - Eric