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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 300E6C31E49 for ; Wed, 19 Jun 2019 09:12:33 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 059B221479 for ; Wed, 19 Jun 2019 09:12:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="XGiufIpu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 059B221479 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jTZlRzMXQKEqHQ+RrbzH7ghxTyRgdoo+u6TKvGjEJMA=; b=XGiufIpuHvo904 PEbr+x37CE0jYLe1TlP6VAGIwviN4T5DRin5eeyUbQ3mgAEORJUOT8wpkDbCDSNsrsCGYL6cmf+rq 9WuFpuDv+t0o6LnCBt1uoBjxX+QbjHQAKE50NLGsYcRDG3dbge2gTbLlcgoYteGjNV6kbKpCeOAXW lGJd6xPtA6H2CUHUQZBHhi61LCGN+D8zwx/7ZzNs53LFl7/9VSyO2k/XqGDR45Am5A17S46wkxDxa szq/DNoMh08ytqjDkWwB58YqsMxqd1aCIFaf732GeXkO7kgVEUk20yAYOBt0ehMKLFadzSeep++0h fbTkJPrRK4CyiVc08X+A==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hdWds-0005Mi-5v; Wed, 19 Jun 2019 09:12:32 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hdWdl-0005EQ-Fk; Wed, 19 Jun 2019 09:12:27 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C1292344; Wed, 19 Jun 2019 02:12:23 -0700 (PDT) Received: from fuggles.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 523053F738; Wed, 19 Jun 2019 02:12:21 -0700 (PDT) Date: Wed, 19 Jun 2019 10:12:19 +0100 From: Will Deacon To: Julien Grall Subject: Re: [PATCH RFC 11/14] arm64: Move the ASID allocator code in a separate file Message-ID: <20190619091219.GB7767@fuggles.cambridge.arm.com> References: <20190321163623.20219-1-julien.grall@arm.com> <20190321163623.20219-12-julien.grall@arm.com> <0dfe120b-066a-2ac8-13bc-3f5a29e2caa3@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.1+86 (6f28e57d73f2) () X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190619_021225_592039_8E770D6A X-CRM114-Status: GOOD ( 14.56 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: julien.thierry@arm.com, aou@eecs.berkeley.edu, james.morse@arm.com, suzuki.poulose@arm.com, Marc Zyngier , catalin.marinas@arm.com, Anup Patel , Palmer Dabbelt , linux-kernel@vger.kernel.org, rppt@linux.ibm.com, hch@infradead.org, Atish.Patra@wdc.com, Guo Ren , gary@garyguo.net, paul.walmsley@sifive.com, christoffer.dall@arm.com, linux-riscv@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 19, 2019 at 09:54:21AM +0100, Julien Grall wrote: > On 6/19/19 9:07 AM, Guo Ren wrote: > > You forgot CCing C-SKY folks :P > > I wasn't aware you could be interested :). > > > Move arm asid allocator code in a generic one is a agood idea, I've > > made a patchset for C-SKY and test is on processing, See: > > https://lore.kernel.org/linux-csky/1560930553-26502-1-git-send-email-guoren@kernel.org/ > > > > If you plan to seperate it into generic one, I could co-work with you. > > Was the ASID allocator work out of box on C-Sky? If so, I can easily move > the code in a generic place (maybe lib/asid.c). This is one place where I'd actually prefer not to go down the route of making the code generic. Context-switching and low-level TLB management is deeply architecture-specific and I worry that by trying to make this code common, we run the real risk of introducing subtle bugs on some architecture every time it is changed. Furthermore, the algorithm we use on arm64 is designed to scale to large systems using DVM and may well be too complex and/or sub-optimal for architectures with different system topologies or TLB invalidation mechanisms. It's not a lot of code, so I don't see that it's a big deal to keep it under arch/arm64. Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel