From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id B378D6B03D6 for ; Wed, 21 Jun 2017 06:40:24 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id u8so171244535pgo.11 for ; Wed, 21 Jun 2017 03:40:24 -0700 (PDT) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id 101si1670449ple.204.2017.06.21.03.40.23 for ; Wed, 21 Jun 2017 03:40:23 -0700 (PDT) Date: Wed, 21 Jun 2017 11:40:17 +0100 From: Catalin Marinas Subject: Re: [PATCHv2 1/3] x86/mm: Provide pmdp_establish() helper Message-ID: <20170621104016.GB10220@e104818-lin.cambridge.arm.com> References: <20170615145224.66200-1-kirill.shutemov@linux.intel.com> <20170615145224.66200-2-kirill.shutemov@linux.intel.com> <20170619152228.GE3024@e104818-lin.cambridge.arm.com> <20170619160005.wgj4nymtj2nntfll@node.shutemov.name> <20170619170911.GF3024@e104818-lin.cambridge.arm.com> <20170619215210.2crwjou3sfdcj73d@node.shutemov.name> <20170620155438.GC21383@e104818-lin.cambridge.arm.com> <20170621095303.q5fqt5a3ao5smko6@node.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170621095303.q5fqt5a3ao5smko6@node.shutemov.name> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: "Kirill A. Shutemov" , Andrew Morton , Vlastimil Babka , Vineet Gupta , Russell King , Will Deacon , Ralf Baechle , "David S. Miller" , "Aneesh Kumar K . V" , Martin Schwidefsky , Heiko Carstens , Andrea Arcangeli , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ingo Molnar , "H . Peter Anvin" , Thomas Gleixner On Wed, Jun 21, 2017 at 12:53:03PM +0300, Kirill A. Shutemov wrote: > On Tue, Jun 20, 2017 at 04:54:38PM +0100, Catalin Marinas wrote: > > For arm64, I don't see the point of a cmpxchg, so something like below > > would do (it needs proper testing though): > > Right. cmpxchg is required for x86 PAE, as it has sizeof(pmd_t) > > sizeof(long). We don't have 8-byte xchg() there. > > Thanks, for the patch. I assume, I can use your signed-off-by, right? Yes. And maybe some text (well, I just copied yours): ---------------8<-------------- arm64: Provide pmdp_establish() helper We need an atomic way to setup pmd page table entry, avoiding races with CPU setting dirty/accessed bits. This is required to implement pmdp_invalidate() that doesn't lose these bits. Signed-off-by: Catalin Marinas ---------------8<-------------- > Any chance you could help me with arm too? I'll have a look. -- Catalin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org