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 47CE7D2AB3C for ; Tue, 29 Oct 2024 13:48:09 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A21DF6B0089; Tue, 29 Oct 2024 09:48:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9D1D86B008A; Tue, 29 Oct 2024 09:48:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 873026B008C; Tue, 29 Oct 2024 09:48:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 67F1F6B0089 for ; Tue, 29 Oct 2024 09:48:08 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 189FB1C43B9 for ; Tue, 29 Oct 2024 13:48:08 +0000 (UTC) X-FDA: 82726767312.09.F1B5874 Received: from mail-qv1-f41.google.com (mail-qv1-f41.google.com [209.85.219.41]) by imf10.hostedemail.com (Postfix) with ESMTP id 24DE8C0018 for ; Tue, 29 Oct 2024 13:47:54 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=gourry.net header.s=google header.b=g+qIsGtr; spf=pass (imf10.hostedemail.com: domain of gourry@gourry.net designates 209.85.219.41 as permitted sender) smtp.mailfrom=gourry@gourry.net; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1730209605; a=rsa-sha256; cv=none; b=vNQ/eBMDOsi1gY39Kvt923VpbBhZXLziuE54+tC0xP4XixsXwT8u7NMNr1W3fKDGu30yp4 Y/noq2RBpOHQlzinxqb3pZAJyWlffmJGaEeVf4E4jjQXXuJ9vPTFbyQiA5XIkYGnAB1064 BhK3ZIw4oBH+MG171ds7AWwEWJIqL18= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=gourry.net header.s=google header.b=g+qIsGtr; spf=pass (imf10.hostedemail.com: domain of gourry@gourry.net designates 209.85.219.41 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=1730209605; 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=uJhl9wZ9AWL6CVmzuzH8pXHXn+O89YeyWJRs5ZMr8IU=; b=tR1u3g9o/+a8OMWuO8f0vCRoYxrSP54FQj4hGr3DVda0Dn1q37wTxgk58JnUKCHo+OgYo6 UD+Kd9sAuCZCzrDP4TsLcSgGJt3M7uGVt0AM+os9YJmpYdnMGxLLQOnhQXU6S38G/v7J1/ MSZJr1R2AqQ+3in8zJDX3nCap4o+agE= Received: by mail-qv1-f41.google.com with SMTP id 6a1803df08f44-6d18cdab29dso19722366d6.0 for ; Tue, 29 Oct 2024 06:48:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gourry.net; s=google; t=1730209685; x=1730814485; 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=uJhl9wZ9AWL6CVmzuzH8pXHXn+O89YeyWJRs5ZMr8IU=; b=g+qIsGtrQoCz2dhGXFG6llEFByoXyd/x0eYQU5yQvJ9JPND8F5LWOlr33Y6qj4zbud rdkeph4C1vifPyUN1KjfgV7cO5qCATkH6i8SyRkkfwdaF/m14DdAale/Reoba5nI+I3z Wyd2Xt/Ok0wW9HlDPI4Jfty5skPtDvs4qfjDSWX/945Y6q4jwhXJoQg/KIEk/2Xfu7Q4 aFZQikTBJj3F8Id5YTuNW8idk11KYZqmRuG2zDwtwIHuDbRNMvQrSd0kZ6euFyQ+UHtO 2hr6dibU76OhCuq6ibat5Pad+BjeXqzS6ZQS12MK2Q5QAlBRIMs2hxa//M1n8lrbOCo4 JxDg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1730209685; x=1730814485; 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=uJhl9wZ9AWL6CVmzuzH8pXHXn+O89YeyWJRs5ZMr8IU=; b=L5fchRLIP5OJZ3yLwMyxdbg2QeVR4IpUVqaMLWrai+boI3K3dYShIay7bRUm3lWf5W /CcL1mRITiZSydv5FnUcZUZeX5lvjRtUtmlwXJr3e9jOecTGwSyj5ZDRUKwuf8zAVFYR yx6PuSHFuLlUBrN+yOZYo9v0rRHgK+M+MnqLWVSr6F4Agme2kddbaj0sQyuRsR/jnQwS ApD+H4PtkwS7Ulp9GBRvbYQ4ozvBpTc/1n0DzpGisagFgOQ77cMFQ938SXIeIK3V2XDl Enp0HJyI0omR7KkOSQLQ+vn4aPkgqVMN9touFdRSZIDAbfsVYDI/RoCYjeijGDCbuBgR ZerQ== X-Forwarded-Encrypted: i=1; AJvYcCVV+JhPupr9259ZgwCvK5MLCcz8QMXSFtWIjMEQU3KMeWY47QS6x060DhBqtoqXwgbHAIvEIwSjeA==@kvack.org X-Gm-Message-State: AOJu0YxlLcaN1+WwCCTTs96CUa4S1p4pZ9veHTZW2FbtG+muXEWZThzu bf+nX+dJskz2o+2KtV8SVwKFCXUVcL/5MesPQ4654mCdwn3C5C27/nYjOEtZZIo= X-Google-Smtp-Source: AGHT+IF1lxr/AwWP0mxrxyPW5aOTDNRVI3XBrynYC+n2D6sorX3YTs7nBHGQWhcBFP84eRt0Jrjj8Q== X-Received: by 2002:a05:6214:5a06:b0:6cd:ef6f:830b with SMTP id 6a1803df08f44-6d1856c45c0mr175242366d6.21.1730209685260; Tue, 29 Oct 2024 06:48:05 -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 6a1803df08f44-6d17991c163sm41438576d6.63.2024.10.29.06.48.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Oct 2024 06:48:04 -0700 (PDT) Date: Tue, 29 Oct 2024 09:48:09 -0400 From: Gregory Price To: David Hildenbrand Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org, linux-cxl@kvack.org, Jonathan.Cameron@huawei.com, dan.j.williams@intel.com, rrichter@amd.com, Terry.Bowman@amd.com, dave.jiang@intel.com, ira.weiny@intel.com, alison.schofield@intel.com, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, rafael@kernel.org, lenb@kernel.org, osalvador@suse.de, gregkh@linuxfoundation.org, akpm@linux-foundation.org, rppt@kernel.org Subject: Re: [PATCH v3 2/3] x86: probe memory block size advisement value during mm init Message-ID: References: <20241022213450.15041-1-gourry@gourry.net> <20241022213450.15041-3-gourry@gourry.net> <07102ea5-ee43-4c11-ab3c-a35cfce9003b@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <07102ea5-ee43-4c11-ab3c-a35cfce9003b@redhat.com> X-Stat-Signature: wtfw1riuxpgk49zuzhdqmm48kjxwa331 X-Rspamd-Queue-Id: 24DE8C0018 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1730209674-268170 X-HE-Meta: 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 ay+T0ZR6 XTc5E1n82XnILf+cISAlg/MhXwE3xZ2QdeU1jo5wiZ313oZNLQ9DalZPREc3359Wb1TW9DlLF3Is5bomChkAVeqXMDJR6sWmljyqGD0DuP24RGTfyInvAwYAibZ1f7VXZwzRs1lAcQT4OqOhuA91RUPauDMQ1heQ4YrJfEOPjx6m7X69Oaf6qh3hHAzjyvhslMTgR8pmH+tNtIHT3fKL0Uvwe+l+N6um7lGmPi/QanX8+YDCEEbgtRtiJuPxLTaWCkJaX1ZJCzyPezwVZC2BOaEjcezfikbOnAoLAyPYLCRcFToWBr6YYDa6KKHJ2m+GES3XbxwtQnA/vVrZuRtVf2PIDrufAU9bj/KD6AXTgz7hD8TkqHvBKrA2Bgg== 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 29, 2024 at 01:40:38PM +0100, David Hildenbrand wrote: > On 22.10.24 23:34, Gregory Price wrote: > > Systems with hotplug may provide an advisement value on what the > > memblock size should be. Probe this value when the rest of the > > configuration values are considered. > > > > The new heuristic is as follows > > > > 1) set_memory_block_size_order value if already set (cmdline param) > > 2) minimum block size if memory is less than large block limit > > 3) if no hotplug advice: Max block size if system is bare-metal, > > otherwise use end of memory alignment. > > 4) if hotplug advice: lesser of advice and end of memory alignment. > > > > Suggested-by: David Hildenbrand > > Signed-off-by: Gregory Price > > --- > > arch/x86/mm/init_64.c | 14 +++++++++----- > > 1 file changed, 9 insertions(+), 5 deletions(-) > > > > diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c > > index ff253648706f..93d669f467f7 100644 > > --- a/arch/x86/mm/init_64.c > > +++ b/arch/x86/mm/init_64.c > > @@ -1452,13 +1452,17 @@ static unsigned long probe_memory_block_size(void) > > } > > /* > > - * Use max block size to minimize overhead on bare metal, where > > - * alignment for memory hotplug isn't a concern. > > + * When hotplug alignment is not a concern, maximize blocksize > > + * to minimize overhead. Otherwise, align to the lesser of advice > > + * alignment and end of memory alignment. > > */ > > - if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) { > > + bz = memory_block_probe_max_size(); > > + if (!bz) { > > bz = MAX_BLOCK_SIZE; > > - goto done; > > - } > > + if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) > > + goto done; > > + } else > > + bz = max(min(bz, MAX_BLOCK_SIZE), MIN_MEMORY_BLOCK_SIZE); > > /* Find the largest allowed block size that aligns to memory end */ > > for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) { ^^^^^^^^^^^^^^^^^^^^^^^^ > > > Acked-by: David Hildenbrand Will pick this up but wanted to point out the silly bug above. This version completely ignores the advise lol. Changing to below diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 93d669f467f7..01876629f21f 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1465,7 +1465,7 @@ static unsigned long probe_memory_block_size(void) bz = max(min(bz, MAX_BLOCK_SIZE), MIN_MEMORY_BLOCK_SIZE); /* Find the largest allowed block size that aligns to memory end */ - for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) { + for (; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) { if (IS_ALIGNED(boot_mem_end, bz)) break; } > > -- > Cheers, > > David / dhildenb >