From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Subject: Re: [PATCH 11/13] m68k/mm: make node data and node setup depend on CONFIG_DISCONTIGMEM Date: Wed, 28 Oct 2020 20:57:41 +0200 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-Transfer-Encoding: quoted-printable Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=nW7k5dFoaVl1Gg4qW9CjoQoQ9yPtdeG5/oR0sb6M5No=; b=XbrdNWGlMpNVIzAqo88imvc0j YGihg+7aKW+vf5TiTmFosPzhHZzHEGfVgk4pR0VCBPyzdFkiFThNHZ1X4nvd8BtUVyr+t+RRNDBJ1 5nsFmBGew8TAQ/vo636Nc9OzZqmqkX4epF7pfzLzDkCRYddVrS+ObRimFFztin2ItO3a7syJ4XA6b beoa4pLjxsljzTcY1wiVPhFo06HJrWpUU7wYSmyF38rJHTRX5edenv8T3gmvGsbbpGYLK9Gj1qaTy hgsu6cmMvR/AoZUPYVH+bHatHBKRD8uyvJf6KvUcTZDaHRtU56Ew9/et+NLzuSXy8ocRwS9i12oaD cS4AKovBg==; 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= Content-Disposition: inline In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane-mx.org@lists.infradead.org To: Michael Schmitz Cc: "linux-ia64@vger.kernel.org" , "open list:DOCUMENTATION" , Catalin Marinas , Linux MM , Will Deacon , Greg Ungerer , Jonathan Corbet , Meelis Roos , Russell King , Mike Rapoport , Geert Uytterhoeven , Matt Turner , arcml , Alexey Dobriyan , linux-m68k , John Paul Adrian Glaubitz , Linux ARM , Tony Luck , Vineet Gupta , Linux Kernel Mailing List , alpha , Linux 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 wrot= e: > > > > From: Mike Rapoport > > > > = > > > > The pg_data_t node structures and their initialization currently de= pends on > > > > !CONFIG_SINGLE_MEMORY_CHUNK. Since they are required only for DISCO= NTIGMEM > > > > make this dependency explicit and replace usage of > > > > CONFIG_SINGLE_MEMORY_CHUNK with CONFIG_DISCONTIGMEM where appropria= te. > > > > = > > > > The CONFIG_SINGLE_MEMORY_CHUNK was implicitly disabled on the ColdF= ire 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 resi= des > 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 a= s=A0 > SINGLE_MEMORY_CHUNK, regardless of bank ordering. I don't think that is w= hat > we really want? It is in a way the case now when !SINGLE_MEMORY_CHUNK =3D=3D 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, > = > =A0=A0=A0 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@linu= x-m68k.org > > > = > > > In personal conversations with technical people, I call myself a hack= er. But > > > when I'm talking to journalists I just say "programmer" or something = like that. > > > -- Linus Torvalds -- = Sincerely yours, Mike.