From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e39.co.us.ibm.com (e39.co.us.ibm.com [32.97.110.160]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e39.co.us.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 1012BB6FA0 for ; Sat, 11 Feb 2012 06:14:26 +1100 (EST) Received: from /spool/local by e39.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 10 Feb 2012 12:14:23 -0700 Received: from d01relay04.pok.ibm.com (d01relay04.pok.ibm.com [9.56.227.236]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id 67103C90063 for ; Fri, 10 Feb 2012 14:14:20 -0500 (EST) Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q1AJEIdE304700 for ; Fri, 10 Feb 2012 14:14:18 -0500 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q1AJEE5d032734 for ; Fri, 10 Feb 2012 12:14:14 -0700 Message-ID: <4F356C7E.3070608@linux.vnet.ibm.com> Date: Fri, 10 Feb 2012 13:14:06 -0600 From: Seth Jennings MIME-Version: 1.0 To: Benjamin Herrenschmidt Subject: Re: tlb flushing on Power References: <4F2160B3.60708@linux.vnet.ibm.com> <4F216620.2010509@linux.vnet.ibm.com> <1327613953.24487.9.camel@pasglop> <4F32B354.7030306@linux.vnet.ibm.com> <1328735054.2903.29.camel@pasglop> In-Reply-To: <1328735054.2903.29.camel@pasglop> Content-Type: text/plain; charset=UTF-8 Cc: Brian King , Robert Jennings , linuxppc-dev@lists.ozlabs.org, Nitin Gupta , Dave Hansen List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 02/08/2012 03:04 PM, Benjamin Herrenschmidt wrote: > >> You can look at https://lkml.org/lkml/2012/1/9/389 in zsmalloc-main.c, >> zs_[un]map_object() functions for the currently uses of set_pte() and >> __flush_tlb_one(). >> >>> set_pte() is long gone on all archs really (or if it's still there it's >>> not meant to be used as is), use set_pte_at(). >> >> Problem with set_pte_at() for us is that we don't have an mm_struct to pass >> because the mapping is not for a userspace process but for the kernel itself. > > Then use init_mm Thanks, that's what I was looking for. >> However, I do think this is the portable function we need to be using. Just >> need to figure out what to pass in for the mm_struct param. >> >>> __flush_tlb_one() doesn't mean anything as an arch independent >>> functionality. We have a local_flush_tlb_page() that -might- do what you >>> want but why in hell is that patch not using proper existing >>> interfaces ? >> >> flush_tlb_page() is the portable function we should be using. However, >> again, it requires a vma_area_struct. I'm not sure what we should be >> passing there. > > Do you need this to be CPU local flush or global ? In the later, > flush_tlb_kernel_range() is the right API. > > If you want per-cpu, we'll have to add a new arch hook. We have interrupts disabled, due to the get_cpu_var() on the percpu variable zs_map_area in zs_map_object(), while the allocation is mapped. So a CPU local would be what we need. -- Seth