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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 D8D21C7618F for ; Mon, 15 Jul 2019 10:58:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B628A206B8 for ; Mon, 15 Jul 2019 10:58:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729880AbfGOK6v (ORCPT ); Mon, 15 Jul 2019 06:58:51 -0400 Received: from foss.arm.com ([217.140.110.172]:47206 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729591AbfGOK6v (ORCPT ); Mon, 15 Jul 2019 06:58:51 -0400 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 E6E292B; Mon, 15 Jul 2019 03:58:50 -0700 (PDT) Received: from [10.1.196.50] (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C68BF3F59C; Mon, 15 Jul 2019 03:58:49 -0700 (PDT) Subject: Re: [RFC v2 11/14] arm64: Move the ASID allocator code in a separate file To: James Morse Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, marc.zyngier@arm.com, julien.thierry@arm.com, suzuki.poulose@arm.com, catalin.marinas@arm.com, will.deacon@arm.com References: <20190620130608.17230-1-julien.grall@arm.com> <20190620130608.17230-12-julien.grall@arm.com> <3e6c6636-8522-ab4a-0183-ae0198a7a047@arm.com> From: Julien Grall Message-ID: <9e605949-4c3f-da9a-228c-25e694ced5df@arm.com> Date: Mon, 15 Jul 2019 11:58:48 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.1 MIME-Version: 1.0 In-Reply-To: <3e6c6636-8522-ab4a-0183-ae0198a7a047@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/07/2019 15:56, James Morse wrote: > Hi Julien, Hi James, Thank you for the review. > > On 20/06/2019 14:06, Julien Grall wrote: >> We will want to re-use the ASID allocator in a separate context (e.g >> allocating VMID). So move the code in a new file. >> >> The function asid_check_context has been moved in the header as a static >> inline function because we want to avoid add a branch when checking if the >> ASID is still valid. > >> diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c >> index 3df63a28856c..b745cf356fe1 100644 >> --- a/arch/arm64/mm/context.c >> +++ b/arch/arm64/mm/context.c >> @@ -23,46 +23,21 @@ > >> -#define ASID_FIRST_VERSION(info) NUM_ASIDS(info) > >> diff --git a/arch/arm64/lib/asid.c b/arch/arm64/lib/asid.c >> new file mode 100644 >> index 000000000000..7252e4fdd5e9 >> --- /dev/null >> +++ b/arch/arm64/lib/asid.c >> @@ -0,0 +1,185 @@ > >> +#define ASID_FIRST_VERSION(info) (1UL << ((info)->bits)) > > (oops!) Good catch, I will fix it in the next version. > > >> @@ -344,7 +115,7 @@ static int asids_init(void) >> if (!asid_allocator_init(&asid_info, bits, ASID_PER_CONTEXT, >> asid_flush_cpu_ctxt)) >> panic("Unable to initialize ASID allocator for %lu ASIDs\n", >> - 1UL << bits); >> + NUM_ASIDS(&asid_info)); > > Could this go in the patch that adds NUM_ASIDS()? Actually this change is potentially wrong. This relies on asid_allocator_init() to set asid_info.bits even if the function fails. So I think it would be best to keep 1UL << bits here. Cheers, -- Julien Grall