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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,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 A57F5C433B4 for ; Fri, 16 Apr 2021 05:26:04 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 0C9876100C for ; Fri, 16 Apr 2021 05:26:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C9876100C 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 boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4FM4SB5Cy8z3bvP for ; Fri, 16 Apr 2021 15:26:02 +1000 (AEST) 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=) 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 4FM4Rp426yz309s for ; Fri, 16 Apr 2021 15:25:41 +1000 (AEST) Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 4FM4Rj5BTJzB09bL; Fri, 16 Apr 2021 07:25:37 +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 IiPlMveTf2d4; Fri, 16 Apr 2021 07:25:37 +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 4FM4Rj3d6HzB09bK; Fri, 16 Apr 2021 07:25:37 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 4E55D8B81C; Fri, 16 Apr 2021 07:25:38 +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 2-smQfjtxhxm; Fri, 16 Apr 2021 07:25:38 +0200 (CEST) Received: from [192.168.4.90] (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 7F75E8B81A; Fri, 16 Apr 2021 07:25:37 +0200 (CEST) Subject: Re: [PATCH v1 4/5] mm: ptdump: Support hugepd table entries To: Daniel Axtens , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Steven Price , akpm@linux-foundation.org References: <87zgxzyvn3.fsf@dja-thinkpad.axtens.net> From: Christophe Leroy Message-ID: <0e7b9312-888c-2e53-b7fd-a887fd9fb429@csgroup.eu> Date: Fri, 16 Apr 2021 07:25:36 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.1 MIME-Version: 1.0 In-Reply-To: <87zgxzyvn3.fsf@dja-thinkpad.axtens.net> 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: linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi Daniel, Le 16/04/2021 à 01:29, Daniel Axtens a écrit : > Hi Christophe, > >> Which hugepd, page table entries can be at any level >> and can be of any size. >> >> Add support for them. >> >> Signed-off-by: Christophe Leroy >> --- >> mm/ptdump.c | 17 +++++++++++++++-- >> 1 file changed, 15 insertions(+), 2 deletions(-) >> >> diff --git a/mm/ptdump.c b/mm/ptdump.c >> index 61cd16afb1c8..6efdb8c15a7d 100644 >> --- a/mm/ptdump.c >> +++ b/mm/ptdump.c >> @@ -112,11 +112,24 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr, >> { >> struct ptdump_state *st = walk->private; >> pte_t val = ptep_get(pte); >> + unsigned long page_size = next - addr; >> + int level; >> + >> + if (page_size >= PGDIR_SIZE) >> + level = 0; >> + else if (page_size >= P4D_SIZE) >> + level = 1; >> + else if (page_size >= PUD_SIZE) >> + level = 2; >> + else if (page_size >= PMD_SIZE) >> + level = 3; >> + else >> + level = 4; >> >> if (st->effective_prot) >> - st->effective_prot(st, 4, pte_val(val)); >> + st->effective_prot(st, level, pte_val(val)); >> >> - st->note_page(st, addr, 4, pte_val(val), PAGE_SIZE); >> + st->note_page(st, addr, level, pte_val(val), page_size); > > It seems to me that passing both level and page_size is a bit redundant, > but I guess it does reduce the impact on each arch's code? Exactly, as shown above, the level can be re-calculated based on the page size, but it would be a unnecessary impact on all architectures and would duplicate the re-calculation of the level whereas in most cases we get it for free from the caller. > > Kind regards, > Daniel > >> >> return 0; >> } >> -- >> 2.25.0