From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id 3C1AB6B03DC for ; Wed, 21 Jun 2017 07:27:10 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id b13so172540028pgn.4 for ; Wed, 21 Jun 2017 04:27:10 -0700 (PDT) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id g5si10386456plm.221.2017.06.21.04.27.09 for ; Wed, 21 Jun 2017 04:27:09 -0700 (PDT) Date: Wed, 21 Jun 2017 12:27:02 +0100 From: Catalin Marinas Subject: Re: [PATCHv2 1/3] x86/mm: Provide pmdp_establish() helper Message-ID: <20170621112702.GC10220@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 Thu, Jun 15, 2017 at 05:52:22PM +0300, Kirill A. Shutemov wrote: > > > > > > > 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 loose these bits. [...] > Any chance you could help me with arm too? On arm (ARMv7 with LPAE) we don't have hardware updates of the access/dirty bits, so a generic implementation would suffice. I didn't find one in your patches, so here's an untested version: static inline pmd_t pmdp_establish(struct mm_struct *mm, unsigned long address, pmd_t *pmdp, pmd_t pmd) { pmd_t old_pmd = *pmdp; set_pmd_at(mm, address, pmdp, pmd); return old_pmd; } -- 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