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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6DCBCCD5BDD for ; Fri, 6 Sep 2024 11:26:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AB5606B0089; Fri, 6 Sep 2024 07:26:54 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A403E6B008A; Fri, 6 Sep 2024 07:26:54 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 906EF6B008C; Fri, 6 Sep 2024 07:26:54 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 727806B0089 for ; Fri, 6 Sep 2024 07:26:54 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 1D9EA16129A for ; Fri, 6 Sep 2024 11:26:54 +0000 (UTC) X-FDA: 82534086348.04.74A7481 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf18.hostedemail.com (Postfix) with ESMTP id 660F41C000F for ; Fri, 6 Sep 2024 11:26:52 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=none; spf=pass (imf18.hostedemail.com: domain of vincenzo.frascino@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=vincenzo.frascino@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1725621987; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DS6YBM/irt8zZgTxPOQUj1xcTFEsBbOY9RvSwdEbj48=; b=hNqqm4eJGO9KEqmHBOcF76MXtEn/E6cgJ1OQysM68cN/JZN4I3qbcyJLwf4sYGx5VFS/ol +Qe+RTm860k3oky7QAaDY3CBd2sYyxDkkmC7Y0xF/mBeqcDt6SXLmIj1pZVVIZiBMhnQBC bv7T4aGLNW5BAvKheFKcMqA89b2PmME= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=none; spf=pass (imf18.hostedemail.com: domain of vincenzo.frascino@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=vincenzo.frascino@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1725621987; a=rsa-sha256; cv=none; b=vschcvD3z02r7RFdEgTxfEkWE7VU+ucvuDqPW4cWXsHTCfyjbZqAvot14n3x8y5CyIHxpd nQ7atGXGqgjYaOlCX+MpIo3s19g62m8HRE4Tj0RN/68+EIOTj2tt69rPyIPzKuvCq6Bq89 6OoqS8cf5JfbsYL9mBEj7Z328nezmLc= 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 A7FD7FEC; Fri, 6 Sep 2024 04:27:18 -0700 (PDT) Received: from [10.1.196.72] (e119884-lin.cambridge.arm.com [10.1.196.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 497F23F73B; Fri, 6 Sep 2024 04:26:49 -0700 (PDT) Message-ID: Date: Fri, 6 Sep 2024 12:26:47 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/9] x86: vdso: Introduce asm/vdso/page.h To: Christophe Leroy , Arnd Bergmann , linux-kernel@vger.kernel.org, Linux-Arch , linux-mm@kvack.org Cc: Andy Lutomirski , Thomas Gleixner , "Jason A . Donenfeld" , Michael Ellerman , Nicholas Piggin , Naveen N Rao , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Theodore Ts'o , Andrew Morton , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers References: <20240903151437.1002990-1-vincenzo.frascino@arm.com> <20240903151437.1002990-4-vincenzo.frascino@arm.com> Content-Language: en-US From: Vincenzo Frascino In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Stat-Signature: 9s17zhfi76pg9m3d7j7ibd86yhxo9yfn X-Rspamd-Queue-Id: 660F41C000F X-Rspamd-Server: rspam11 X-HE-Tag: 1725622012-777293 X-HE-Meta: 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 jPs0Nenz f5nGq8THlqMkkUGGqtzcf0it8fjaUcNeI/afABed5BVqWo6QuGgdx81pf1jOtXEi7PEESYy7WC5Orc1ovPP/nPNlnaW2LDbuoWU1ab4gkw9SXsmsc4o+lPUXtYGxE/n41RBSYPM7MiNjS8p0eE9/uQMfPuAbH7fdBdrA8JQNOPVp6Y5k= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 04/09/2024 16:05, Christophe Leroy wrote: > > > Le 04/09/2024 à 16:52, Arnd Bergmann a écrit : >> On Tue, Sep 3, 2024, at 15:14, Vincenzo Frascino wrote: >> ... >>> + >>> +#ifndef __ASSEMBLY__ >>> + >>> +#include >>> + >>> +#define VDSO_PAGE_MASK    PAGE_MASK >>> +#define VDSO_PAGE_SIZE    PAGE_SIZE >>> + >>> +#endif /* !__ASSEMBLY__ */ >>> + >>> +#endif /* __ASM_VDSO_PAGE_H */ >> >> I don't get this one: the x86 asm/page_types.h still includes other >> headers outside of the vdso namespace, but you seem to only need these >> two definitions that are the same across everything. >> >> Why not put PAGE_MASK and PAGE_SIZE into a global vdso/page.h >> header? I did spend a lot of time a few months ago ensuring that >> we can have a single definition for all architectures based on >> CONFIG_PAGE_SHIFT, so all the extra copies should just go away. >> > > Just wondering, after looking at x86, powerpc and arm64, is there any difference > between: > > X86,ARM64: > #define PAGE_SIZE        (_AC(1,UL) << PAGE_SHIFT) > #define PAGE_MASK        (~(PAGE_SIZE-1)) > > POWERPC: > #define PAGE_SIZE        (ASM_CONST(1) << PAGE_SHIFT) > /* >  * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we >  * assign PAGE_MASK to a larger type it gets extended the way we want >  * (i.e. with 1s in the high bits) >  */ > #define PAGE_MASK      (~((1 << PAGE_SHIFT) - 1)) > > > Which one should be taken in vdso/page.h ? > I am not sure either on this point. That's the main reason why I proposed an indirection for the definitions. > Christophe -- Regards, Vincenzo