From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f72.google.com (mail-lf0-f72.google.com [209.85.215.72]) by kanga.kvack.org (Postfix) with ESMTP id 729A06B0038 for ; Sat, 17 Dec 2016 02:34:12 -0500 (EST) Received: by mail-lf0-f72.google.com with SMTP id o20so12935298lfg.2 for ; Fri, 16 Dec 2016 23:34:12 -0800 (PST) Received: from asavdk4.altibox.net (asavdk4.altibox.net. [109.247.116.15]) by mx.google.com with ESMTPS id u63si5804923lja.19.2016.12.16.23.34.10 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 16 Dec 2016 23:34:10 -0800 (PST) Date: Sat, 17 Dec 2016 08:34:06 +0100 From: Sam Ravnborg Subject: Re: [RFC PATCH 02/14] sparc64: add new fields to mmu context for shared context support Message-ID: <20161217073406.GA23567@ravnborg.org> References: <1481913337-9331-1-git-send-email-mike.kravetz@oracle.com> <1481913337-9331-3-git-send-email-mike.kravetz@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1481913337-9331-3-git-send-email-mike.kravetz@oracle.com> Sender: owner-linux-mm@kvack.org List-ID: To: Mike Kravetz Cc: sparclinux@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "David S . Miller" , Bob Picco , Nitin Gupta , Vijay Kumar , Julian Calaby , Adam Buchbinder , "Kirill A . Shutemov" , Michal Hocko , Andrew Morton Hi Mike. On Fri, Dec 16, 2016 at 10:35:25AM -0800, Mike Kravetz wrote: > Add new fields to the mm_context structure to support shared context. > Instead of a simple context ID, add a pointer to a structure with a > reference count. This is needed as multiple tasks will share the > context ID. What are the benefits with the shared_mmu_ctx struct? It does not save any space in mm_context_t, and the CPU only supports one extra context. So it looks like over-engineering with all the extra administration required to handle it with refcount, poitners etc. what do I miss? Sam -- 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