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=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 421A8C4363A for ; Wed, 21 Oct 2020 10:34:40 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0B4B422249 for ; Wed, 21 Oct 2020 10:34:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0B4B422249 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=csgroup.eu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4CGRgv6RdzzDqMW for ; Wed, 21 Oct 2020 21:34:35 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=csgroup.eu (client-ip=93.17.236.30; helo=pegase1.c-s.fr; envelope-from=christophe.leroy@csgroup.eu; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=csgroup.eu Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4CGRf30nHGzDqMW for ; Wed, 21 Oct 2020 21:32:52 +1100 (AEDT) Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 4CGRdp4V1FzB09bF; Wed, 21 Oct 2020 12:32:46 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id jnZ2Vh4Sltdf; Wed, 21 Oct 2020 12:32:46 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 4CGRdp39xqzB09bB; Wed, 21 Oct 2020 12:32:46 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 7E52C8B7F6; Wed, 21 Oct 2020 12:32:47 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id 8NBdCwGsqdJN; Wed, 21 Oct 2020 12:32:47 +0200 (CEST) Received: from [172.25.230.100] (po15451.idsi0.si.c-s.fr [172.25.230.100]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 5762E8B7EA; Wed, 21 Oct 2020 12:32:47 +0200 (CEST) Subject: Re: [PATCH v2] powerpc/mm: Add mask of always present MMU features From: Christophe Leroy To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman References: <06bf0e094463533e7aec6900bddd435171e9f44f.1602517171.git.christophe.leroy@csgroup.eu> Message-ID: <4bc99005-f3c0-045b-e0d5-f8b6f2b2e90d@csgroup.eu> Date: Wed, 21 Oct 2020 12:32:39 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 MIME-Version: 1.0 In-Reply-To: <06bf0e094463533e7aec6900bddd435171e9f44f.1602517171.git.christophe.leroy@csgroup.eu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Le 12/10/2020 à 17:39, Christophe Leroy a écrit : > On the same principle as commit 773edeadf672 ("powerpc/mm: Add mask > of possible MMU features"), add mask for MMU features that are > always there in order to optimise out dead branches. > > Signed-off-by: Christophe Leroy > --- > v2: Features must be anded with MMU_FTRS_POSSIBLE instead of ~0, otherwise > MMU_FTRS_ALWAYS is ~0 when no #ifdef matches. This is still not enough. For BOOK3S/32, MMU_FTRS_POSSIBLE is still too much. We need a #ifdef CONFIG_PPC_BOOK3S_32 with 0. Christophe > --- > arch/powerpc/include/asm/mmu.h | 25 +++++++++++++++++++++++++ > 1 file changed, 25 insertions(+) > > diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h > index 255a1837e9f7..64e7e7f7cda9 100644 > --- a/arch/powerpc/include/asm/mmu.h > +++ b/arch/powerpc/include/asm/mmu.h > @@ -201,8 +201,30 @@ enum { > 0, > }; > > +enum { > + MMU_FTRS_ALWAYS = > +#ifdef CONFIG_PPC_8xx > + MMU_FTR_TYPE_8xx & > +#endif > +#ifdef CONFIG_40x > + MMU_FTR_TYPE_40x & > +#endif > +#ifdef CONFIG_PPC_47x > + MMU_FTR_TYPE_47x & > +#elif defined(CONFIG_44x) > + MMU_FTR_TYPE_44x & > +#endif > +#if defined(CONFIG_E200) || defined(CONFIG_E500) > + MMU_FTR_TYPE_FSL_E & > +#endif > + MMU_FTRS_POSSIBLE, > +}; > + > static inline bool early_mmu_has_feature(unsigned long feature) > { > + if (MMU_FTRS_ALWAYS & feature) > + return true; > + > return !!(MMU_FTRS_POSSIBLE & cur_cpu_spec->mmu_features & feature); > } > > @@ -231,6 +253,9 @@ static __always_inline bool mmu_has_feature(unsigned long feature) > } > #endif > > + if (MMU_FTRS_ALWAYS & feature) > + return true; > + > if (!(MMU_FTRS_POSSIBLE & feature)) > return false; > >