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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F1EB0C56201 for ; Thu, 29 Oct 2020 00:23:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B412B207DE for ; Thu, 29 Oct 2020 00:23:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603931039; bh=zK9DfVuZHDzMdXj+yhDB8KulDOu8wW0+2VHqzzJ4VCs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=rQD18QY3SCirt0vRNJxyPq5apPkKQP9B/dRQpBBN/r/TS/eEEjXi3gj5oNt8n6T2P F45kCeamuwdmDqyIRAwfJgL9jTsfe+drE6qIUs7lR/cTOw5VaeY3MS+8HiE4bq9Xr1 HpN6DbA+st3hmJ32YWmtX4ypRLLEG6+3hZiCoC8s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388491AbgJ2AX5 (ORCPT ); Wed, 28 Oct 2020 20:23:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:49590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388464AbgJ1WhY (ORCPT ); Wed, 28 Oct 2020 18:37:24 -0400 Received: from kernel.org (unknown [87.70.96.83]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1B5552473E; Wed, 28 Oct 2020 18:57:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603911472; bh=zK9DfVuZHDzMdXj+yhDB8KulDOu8wW0+2VHqzzJ4VCs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=0wRwxQSg4yE6tWskIfT82ofwXzSEJ/5NZugomFl0MhuujRXgT16OkYNSNiruGCQgb 4FmuFCHOOX4U7+tixFCp9eSridGpAq2f1ngfZ2ujosWNGX6mwHBQzCWsAku7+1/9jF 4Ekc11AXMUb29fsDTzF2sQtG1jcmaJnC2BBUIYCs= Date: Wed, 28 Oct 2020 20:57:41 +0200 From: Mike Rapoport To: Michael Schmitz Cc: Geert Uytterhoeven , Andrew Morton , Alexey Dobriyan , Catalin Marinas , Greg Ungerer , John Paul Adrian Glaubitz , Jonathan Corbet , Matt Turner , Meelis Roos , Mike Rapoport , Russell King , Tony Luck , Vineet Gupta , Will Deacon , alpha , Linux ARM , "open list:DOCUMENTATION" , Linux FS Devel , "linux-ia64@vger.kernel.org" , Linux Kernel Mailing List , linux-m68k , Linux MM , arcml Subject: Re: [PATCH 11/13] m68k/mm: make node data and node setup depend on CONFIG_DISCONTIGMEM Message-ID: <20201028185741.GI1428094@kernel.org> References: <20201027112955.14157-1-rppt@kernel.org> <20201027112955.14157-12-rppt@kernel.org> <20201028111631.GF1428094@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 29, 2020 at 07:14:38AM +1300, Michael Schmitz wrote: > Hi Mike, > > On 29/10/20 12:16 AM, Mike Rapoport wrote: > > Hi Geert, > > > > On Wed, Oct 28, 2020 at 10:25:49AM +0100, Geert Uytterhoeven wrote: > > > Hi Mike, > > > > > > On Tue, Oct 27, 2020 at 12:31 PM Mike Rapoport wrote: > > > > From: Mike Rapoport > > > > > > > > The pg_data_t node structures and their initialization currently depends on > > > > !CONFIG_SINGLE_MEMORY_CHUNK. Since they are required only for DISCONTIGMEM > > > > make this dependency explicit and replace usage of > > > > CONFIG_SINGLE_MEMORY_CHUNK with CONFIG_DISCONTIGMEM where appropriate. > > > > > > > > The CONFIG_SINGLE_MEMORY_CHUNK was implicitly disabled on the ColdFire MMU > > > > variant, although it always presumed a single memory bank. As there is no > > > > actual need for DISCONTIGMEM in this case, make sure that ColdFire MMU > > > > systems set CONFIG_SINGLE_MEMORY_CHUNK to 'y'. > > > > > > > > Signed-off-by: Mike Rapoport > > > Thanks for your patch! > > > > > > > --- > > > > arch/m68k/Kconfig.cpu | 6 +++--- > > > > arch/m68k/include/asm/page_mm.h | 2 +- > > > > arch/m68k/mm/init.c | 4 ++-- > > > > 3 files changed, 6 insertions(+), 6 deletions(-) > > > Is there any specific reason you didn't convert the checks for > > > CONFIG_SINGLE_MEMORY_CHUNK in arch/m68k/kernel/setup_mm.c > > In arch/m68k/kernel/setup_mm.c the CONFIG_SINGLE_MEMORY_CHUNK is needed > > for the case when a system has two banks, the kernel is loaded into the > > second bank and so the first bank cannot be used as normal memory. It > > does not matter what memory model will be used in this case. > > > That case used to be detected just fine at run time (by dint of the second > memory chunk having an address below the first; the chunk the kernel resides > in is always listed first), even without using CONFIG_SINGLE_MEMORY_CHUNK. Right, CONFIG_SINGLE_MEMORY_CHUNK in arch/m68k/kernel/setup_mm.c is used to force using a single bank of memory regardless of run time detection. > Unless you changed that behaviour (and I see nothing in your patch that > would indicate that), this is still true. > > Converting the check as Geert suggested, without also adding a test for > out-of-order memory bank addresses, would implicitly treat DISCONTIGMEM as  > SINGLE_MEMORY_CHUNK, regardless of bank ordering. I don't think that is what > we really want? It is in a way the case now when !SINGLE_MEMORY_CHUNK == DISCONTIGMEM. So forcing SIGNLE_MEMORY_CHUNK at compile time would also mean forcing FLATMEM. After these changes I think SINGLE_MEMORY_CHUNK is not needed at all. > Cheers, > >     Michael > > > > > > > and arch/m68k/include/asm/virtconvert.h? > > I remember I had build errors and troubles with include file > > dependencies if I changed it there, but I might be mistaken. I'll > > recheck again. > > > > > Gr{oetje,eeting}s, > > > > > > Geert > > > > > > -- > > > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > > > > > In personal conversations with technical people, I call myself a hacker. But > > > when I'm talking to journalists I just say "programmer" or something like that. > > > -- Linus Torvalds -- Sincerely yours, Mike.