From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from elvis.franken.de (elvis.franken.de [193.175.24.41]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 0DDEEB66C; Sat, 30 Dec 2023 15:39:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alpha.franken.de Received: from uucp by elvis.franken.de with local-rmail (Exim 3.36 #1) id 1rJacF-0004OV-00; Sat, 30 Dec 2023 15:47:07 +0100 Received: by alpha.franken.de (Postfix, from userid 1000) id 8EE31C028A; Sat, 30 Dec 2023 15:40:51 +0100 (CET) Date: Sat, 30 Dec 2023 15:40:51 +0100 From: Thomas Bogendoerfer To: Jiaxun Yang Cc: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] MIPS: Enable SPARSEMEM option unconditionally on 64BIT Message-ID: References: <20231028-mm-v1-0-45377cd158cf@flygoat.com> <20231028-mm-v1-1-45377cd158cf@flygoat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231028-mm-v1-1-45377cd158cf@flygoat.com> On Sat, Oct 28, 2023 at 02:52:16PM +0100, Jiaxun Yang wrote: > SPARSEMEM have been tested on Cavium and Loongson64 for a while > and we are confident that they are working properly on 64bit > systems. > > Since it's almost certain for 64bit MIPS system to have a hole > in memory space, SPARSEMEM will be more efficent for them. > > Also promote platforms marked with SPARSEMEM_ENABLE before > to SPARSEMEM_DEFAULT, as they tend to have huge holes in > address space. > > Signed-off-by: Jiaxun Yang > --- > arch/mips/Kconfig | 13 ++++++++----- > arch/mips/loongson2ef/Kconfig | 4 ++-- > 2 files changed, 10 insertions(+), 7 deletions(-) > > diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig > index 76db82542519..d12e8f3c1d08 100644 > --- a/arch/mips/Kconfig > +++ b/arch/mips/Kconfig > @@ -460,7 +460,7 @@ config MACH_LOONGSON2EF > > config MACH_LOONGSON64 > bool "Loongson 64-bit family of machines" > - select ARCH_SPARSEMEM_ENABLE > + select ARCH_SPARSEMEM_DEFAULT > select ARCH_MIGHT_HAVE_PC_PARPORT > select ARCH_MIGHT_HAVE_PC_SERIO > select GENERIC_ISA_DMA_SUPPORT_BROKEN > @@ -656,7 +656,7 @@ config SGI_IP22 > config SGI_IP27 > bool "SGI IP27 (Origin200/2000)" > select ARCH_HAS_PHYS_TO_DMA > - select ARCH_SPARSEMEM_ENABLE > + select ARCH_SPARSEMEM_DEFAULT > select FW_ARC > select FW_ARC64 > select ARC_CMDLINE_ONLY > @@ -923,7 +923,7 @@ config CAVIUM_OCTEON_SOC > select ZONE_DMA32 > select GPIOLIB > select USE_OF > - select ARCH_SPARSEMEM_ENABLE > + select ARCH_SPARSEMEM_DEFAULT > select SYS_SUPPORTS_SMP > select NR_CPUS_DEFAULT_64 > select MIPS_NR_CPU_NR_MAP_1024 > @@ -2573,10 +2573,13 @@ config CPU_SUPPORTS_MSA > > config ARCH_FLATMEM_ENABLE > def_bool y > - depends on !NUMA && !CPU_LOONGSON2EF > > config ARCH_SPARSEMEM_ENABLE > - bool > + def_bool y > + depends on 64BIT > + > +config ARCH_SELECT_MEMORY_MODEL > + def_bool ARCH_SPARSEMEM_ENABLE maybe I'm blind, but I don't see ARCH_SPARSEMEM_DEFAULT declared in Kconfig for MIPS. So what I'm missing ? Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]