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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5653CEF172 for ; Tue, 8 Oct 2024 14:51:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3C1186B007B; Tue, 8 Oct 2024 10:51:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 34A4C6B0085; Tue, 8 Oct 2024 10:51:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1EB656B0089; Tue, 8 Oct 2024 10:51:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id F0A7F6B007B for ; Tue, 8 Oct 2024 10:51:41 -0400 (EDT) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 5B5038033D for ; Tue, 8 Oct 2024 14:51:40 +0000 (UTC) X-FDA: 82650724002.08.D9D5BE4 Received: from mail-qk1-f182.google.com (mail-qk1-f182.google.com [209.85.222.182]) by imf05.hostedemail.com (Postfix) with ESMTP id A751210000E for ; Tue, 8 Oct 2024 14:51:39 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=gourry.net header.s=google header.b="PTkVB/Wu"; spf=pass (imf05.hostedemail.com: domain of gourry@gourry.net designates 209.85.222.182 as permitted sender) smtp.mailfrom=gourry@gourry.net; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1728398964; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=o+8u49KVyhPOrweO2lc6eBFQS+Hc6vnffHct6u8Jv+w=; b=g4n66WpMpuFBy/PkMfYAhjXwkkjRf7CWYm4V0eJRpe4Cjf+svkuT2W/qb89NL6Rvrnt5YO 2+lVqDqFFV1CInA/u6LxP239ie1GaGYdl/F39xR8LLBzHw6p3lpcDAzZ4zfVeol+TuSAKz WbiLkvTnGhJgpv2D0LPEo7jtX+Xgpy4= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1728398964; a=rsa-sha256; cv=none; b=xbFX1nWHm6bdiG0JZ3tfyINII5kiLgdaLNtfrmvlQHxxsCDEeMIpPr8XvzcFZyqsXZy14M jjaG0LBid2UgzO+81/I9SH5khKhu4oPRzcfC89nW4Y2tNXpkVX+Q5XQvQtxql82IX6n3H6 ul4qfOw/mIp9GmlDWZhv2k1b8ezrEAc= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=gourry.net header.s=google header.b="PTkVB/Wu"; spf=pass (imf05.hostedemail.com: domain of gourry@gourry.net designates 209.85.222.182 as permitted sender) smtp.mailfrom=gourry@gourry.net; dmarc=none Received: by mail-qk1-f182.google.com with SMTP id af79cd13be357-7a99e8d5df1so575750485a.2 for ; Tue, 08 Oct 2024 07:51:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gourry.net; s=google; t=1728399099; x=1729003899; darn=kvack.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=o+8u49KVyhPOrweO2lc6eBFQS+Hc6vnffHct6u8Jv+w=; b=PTkVB/Wujl3ogS+sH1ppkLE7iOT5eO/rVgvmncSlfKghhXVnIFD0tDS2HDIAaBGUhz 9uE99c2r7AzjPJlYCtAnDVdyCyEBprQPiVqK8OPXdzr2lxKp//GI1DoENv9RWdkkz57r zLhkxCDgV7Vf7b3xgwbh9nDWqgnoC8I/iCIlY1IyffCEp8qP1hrypXrgv9ga84TpUFYi 3rN0+PcRPnyhyt7xILnre4+YQ4PkB7PvcXNw28RlD9YtD0KzbGkOwLmTcBorypzNLVo/ Nfo1IgT24EPALdEJxm4D+DHt0Ly1oYSAIGJlc9pMnHyr9ju9aHdwp/NEIdpC9poMuW7C q3IQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728399099; x=1729003899; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=o+8u49KVyhPOrweO2lc6eBFQS+Hc6vnffHct6u8Jv+w=; b=S1YXNGfkNLwxsdW6BbADfohuiWHWv82lIn3eiyzdQQqqs76NSbuLYvNNq9iMluBNa2 r0QHwn+n/2SD2SjSP1CUfI3Ib9knHFtdfWErVaCrLtlvd2GkJHBDfu87FGGg6un43FBf rT+RpUfGp95dr0qwj8OurzAqhSQrOoVTS+9ddG01D2wJY2YpwMdxjckVKQuSWpjEMelT 49MOHnI8rMJwlo51rv+/Z2883M2D16aBpsV2BSLZmdePLWtc4LWfSz8feme0CcCCwfCY N3xcayCjCwZtOFJR15GPz6pSc8QXPtk1Lg21QEk31WvmRL4KQr8gZgNwCb55dXeze+Cj zJyA== X-Forwarded-Encrypted: i=1; AJvYcCX80SlBRzcy/J0tD3ljJZAh+pU+jyata8Fgebd3tB25VwHohWdxZrHeEc6RqtZ7OV/b9g5QfDbODg==@kvack.org X-Gm-Message-State: AOJu0Ywmgt/CQpmparN+7ZZjoNXD0nf96UrWVEE1wRgK4CrfB/Z3cdqg 2h4xSe0VuSfIy028eFSg6VgvaW/S+SD6BZBI8oC/KZLpFhM0VE86q4EJJ/Nt5WE= X-Google-Smtp-Source: AGHT+IFq4ejAZimMFPt1747gCyE+Qz23dQBrY1mL0z6fT+fBj1wX7llJiqwXX1zCd9TNFYGsXrL5tg== X-Received: by 2002:a05:620a:29c4:b0:7ac:e30e:f6f with SMTP id af79cd13be357-7ae6f48699fmr2414673785a.43.1728399098773; Tue, 08 Oct 2024 07:51:38 -0700 (PDT) Received: from PC2K9PVX.TheFacebook.com (pool-173-79-56-208.washdc.fios.verizon.net. [173.79.56.208]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7ae75635ca8sm360029085a.60.2024.10.08.07.51.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Oct 2024 07:51:38 -0700 (PDT) Date: Tue, 8 Oct 2024 10:51:29 -0400 From: Gregory Price To: David Hildenbrand Cc: linux-cxl@vger.kernel.org, x86@kernel.org, linux-mm@kvack.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, osalvador@suse.de, gregkh@linuxfoundation.org, rafael@kernel.org, akpm@linux-foundation.org, dan.j.williams@intel.com, Jonathan.Cameron@huawei.com, alison.schofield@intel.com, rrichter@amd.com, terry.bowman@amd.com, lenb@kernel.org, dave.jiang@intel.com, ira.weiny@intel.com Subject: Re: [PATCH 1/3] memory: extern memory_block_size_bytes and set_memory_block_size_order Message-ID: References: <20241008044355.4325-1-gourry@gourry.net> <20241008044355.4325-2-gourry@gourry.net> <039e8c87-c5da-4469-b10e-e57dd5662cff@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <039e8c87-c5da-4469-b10e-e57dd5662cff@redhat.com> X-Stat-Signature: 6hioxazrwq1z3mr4w6is8yx3qqsrkqxx X-Rspamd-Queue-Id: A751210000E X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1728399099-855113 X-HE-Meta: U2FsdGVkX18qo0gqZvG8Ez823S9BWIshZjogW+J0OIQAPmnqywd2S0Pszwh+df2+MFhmsc5OF3RJ7CjicgiOUauGoT7yvdIYLW4vrsoH7VQ35L3+FNcsT/SYDudlbVAJ2DzbGkKL1VtybXhzbPJ9LsQG1pOX0V4R4ig9AZ0JwJzRhDbUXmcZZI32pgft77Pf9bvlIc8OZz5k/GEvcuYW8uoTGouJeKr7jkQ7ngNxItxm6w/Ve9blALJ1thU2tJk8ie0zb1rD6w8AWWVEeIO7T7I2O8CYJO4vtqEAcXvBNNTa8VIrM8Aoi3ZA6MwRANBqJiM6urC8odMH3AKfFJriFgXCApSbiiTpW7Ih9+/1+X9Dvr8uyD+i0osKYtcYV/8//00S933Dhc8qF0coHgzZsO2TJv53tqUm4/cCP6mqOMti4LsLSbG3vPyD7QOiR+9Dl2oKnfvV0m3+TiTZzt6N1mBSDt5s7+Hy3/mjVBz5/HNSJ0kr4D6qQSBj1tSsOWFRx5IF75k9XX1YPwal0VEq3etN35zr2sEQv8+eNoCiFhziLI1XJVqxk+IBqFRiDxlrQ6UAzZ5GgqjmQkFj+42ox+0CtxtMIxeafsgV9fTAag93SyMNsWH1uKNke9Kw2sQ6xKAw9JS2x3ghKBqaJoPzzGzt4ypr+BvkWxV1u1N/2zwTPk7ljORJOmZmeM/4TqMR97q+Bfl6IPf2TFZ73KUjG5K3WT2u53NBHQi0QMgIVlSe0IQr7OJ+1R+6ewXSLWpEV5QBjdM752FJZJ1PKCY4AnswTDsdxMtxPTct3jQ41SCmAb5wiWlISQFc0P5R0KRd3SeLMeViVMRcDERLP/EjDKcbwq5PnL6WXSYXmV6X6r7+Dx9c6yeVQ/EvEP8ukTI2s+aUv0CO57fL6ojxxv1jQSUahfONN4RJuRunJsdlodIoP0M8uXIbLhTZ8LWEgPO6vhyHp0ViH2ZO7ZBznW7 YeAqtUrM Tfszf70dwCQjMatVJps5y41wv7h/ZiBffmCRwdIsieiCB5K3LYIBiGmdN6iZpg+QZSzmLlQf0MCd+FbbWBZZRbKCXUU4035H9ehZOZYwFLpSnR4l4pDslRgnOkSmEYTCYGnJrDoS+3I5fCxn2khyk3u5N0hncgp+DAbPas0KlA86qPu3eEbU/F6OpCGJkHo3rokSXujApND7AHcxxsYL/SmQOn04dOFsCiDLUFOHotFdzQAL/KFrt+PYyZsbPxJt9LwxqZQEaDi/7Bttymn/YOo41702t7nzCQYK40NKEgW1T5o4fHkhJpoBvbwkByWfnDCkm4cLgXodMkeCh0G2T6Hh1qid19Le0rKXGXfv9IoKHZZD7DoTW8SU3P6bb3JEmr80adCUowLz18xM= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Oct 08, 2024 at 04:03:37PM +0200, David Hildenbrand wrote: > On 08.10.24 06:43, Gregory Price wrote: > > On CXL systems, block alignment may be as small as 256MB, which may > > require a resize of the block size during initialization. This is done > > in the ACPI driver, so the resize function need to be made available. > > > > Presently, only x86 provides the functionality to resize memory > > block sizes. Wire up a weak stub for set_memory_block_size_order, > > similar to memory_block_size_bytes, that simply returns -ENODEV. > > > > Since set_memory_block_size_order is now extern, we also need to > > drop the __init macro. > > > > Signed-off-by: Gregory Price > > --- > > arch/x86/mm/init_64.c | 2 +- > > drivers/base/memory.c | 6 ++++++ > > include/linux/memory.h | 4 ++-- > > 3 files changed, 9 insertions(+), 3 deletions(-) > > > > diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c > > index ff253648706f..6086f99449fa 100644 > > --- a/arch/x86/mm/init_64.c > > +++ b/arch/x86/mm/init_64.c > > @@ -1424,7 +1424,7 @@ void mark_rodata_ro(void) > > /* Adjustable memory block size */ > > static unsigned long set_memory_block_size; > > -int __init set_memory_block_size_order(unsigned int order) > > +int set_memory_block_size_order(unsigned int order) > > { > > unsigned long size = 1UL << order; > > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > > index 67858eeb92ed..f9045642f69e 100644 > > --- a/drivers/base/memory.c > > +++ b/drivers/base/memory.c > > @@ -110,6 +110,12 @@ static void memory_block_release(struct device *dev) > > kfree(mem); > > } > > +int __weak set_memory_block_size_order(unsigned int order) > > +{ > > + return -ENODEV; > > +} > > +EXPORT_SYMBOL_GPL(set_memory_block_size_order); > > I can understand what you are trying to achieve, but letting arbitrary > modules mess with this sounds like a bad idea. > I suppose the alternative is trying to scan the CEDT from inside each machine, rather than the ACPI driver? Seems less maintainable. I don't entirely disagree with your comment. I hummed and hawwed over externing this - hence the warning in the x86 machine. Open to better answers. > -- > Cheers, > > David / dhildenb >