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 DDBA4E6F06D for ; Fri, 1 Nov 2024 16:19:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5F61E6B0083; Fri, 1 Nov 2024 12:19:16 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 57F626B0085; Fri, 1 Nov 2024 12:19:16 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3F87B6B0088; Fri, 1 Nov 2024 12:19:16 -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 1E8586B0083 for ; Fri, 1 Nov 2024 12:19:16 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 97F6E409A1 for ; Fri, 1 Nov 2024 16:19:15 +0000 (UTC) X-FDA: 82738035282.18.1977CCB Received: from mail-qv1-f43.google.com (mail-qv1-f43.google.com [209.85.219.43]) by imf27.hostedemail.com (Postfix) with ESMTP id ADE2840012 for ; Fri, 1 Nov 2024 16:18:44 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=gourry.net header.s=google header.b=PecUhIEp; spf=pass (imf27.hostedemail.com: domain of gourry@gourry.net designates 209.85.219.43 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=1730477774; 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=/bSsmwzcmIHT5+RxiruYL3qxqOwdT7Crq4ILwrDDOp0=; b=zcgNggf6Bobm0RUvpkf9ZaHsuSwHSiKcJMJ+YEgSPqdk0iEOgHF3O2jOId8J9CYDAfY9t4 bb28kUWCbg7rsQ/MktaHzIq2eY9558pZ+wxdym0kMpQucXN0AWD5aHinfwQajihO7LSOb/ XQecHqOkucOYB3RjrNvyA8pYMiO+ZaU= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=gourry.net header.s=google header.b=PecUhIEp; spf=pass (imf27.hostedemail.com: domain of gourry@gourry.net designates 209.85.219.43 as permitted sender) smtp.mailfrom=gourry@gourry.net; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1730477774; a=rsa-sha256; cv=none; b=D6xjMfBshC+JrKkLeI5fsVkQYucOupXK3MCqb2KSvcnJeOtFHkEDrT8XPt+pT9x7DYfC1j ZOL+ISWE2WVsaiZDijkHCDomaj6vJ6SbVnarMcYFqPgjuSFJ4Higuze4GHDcDYxwLm9fHN 2B36wEcaXr2B6OVl5La9PRm183PlauE= Received: by mail-qv1-f43.google.com with SMTP id 6a1803df08f44-6cbd092f7f0so14946876d6.0 for ; Fri, 01 Nov 2024 09:19:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gourry.net; s=google; t=1730477952; x=1731082752; 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=/bSsmwzcmIHT5+RxiruYL3qxqOwdT7Crq4ILwrDDOp0=; b=PecUhIEpxU38K1GCwgwbf4oM5kJou0CVv7Jwjia8ymXuusNQpyhqAXMiZnHYN2xY4b BgCrEq4oUymj2bEZDbV4p/KWV3y5ZufEWrwTQ0V+/2BhKxGjeCP0t4ZG9P2qwhJdq8yM Cf7je/Gfw89VOs2xJzGaDwjJZNeVSCYxQfdwdqzI+oCofNbncxuvukv2bBA1CZYzR1rU EZgGxs+FbXJeKRZuv26/o7AVCmMfT6GqRzzSwekqb7Qpr+Z49iDk4Xme91MzLjrF9LCs pDHyjjL3mbkEFjkKNCBklPp9vkjxsLd3rULJytJBHCzRZwQVPQJna/ShmdAi0Xd6Tio+ s9Vg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1730477952; x=1731082752; 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=/bSsmwzcmIHT5+RxiruYL3qxqOwdT7Crq4ILwrDDOp0=; b=Ld6uL65+GuBHv/ntIhWOu+SWOtl0k1VYuHMDrQcGMURCnzysfyzx2jjsu/AwiavW9K qSksmUxxoa0Th1hTbeFWSvH5G1ilgvMriTkSUUjCd+0WT1HtCrlpEz25kjIDw67nzeOl s7jfTTZq6y742QIjX59lXlP2N1d/C+DbaB8A9VDYs535+z3U0QAoh/iZq8f9y/lyq2Qu 61lGj6QUfZRs9UBzmsa4tEvLlu9uIsc3pWWYnvsQRrfQddVVhLM3Wb84JYb2tzDelEvB a7B6OkiNQqep9tdaOI8QAr9fzIQJxjFW6xB6+fFsJ9KwHcQ8cZfLhzdpEQFMMu0xnZPQ xGAw== X-Forwarded-Encrypted: i=1; AJvYcCX8cf8RklIE/p9ejpeD0FdmzUIRiTD+OzvyIUP1L3RdZb+V7/Qc4eDqsMYsk+fihNSxPvMOc05C7A==@kvack.org X-Gm-Message-State: AOJu0Yw/CWyc5zy7dy9GmikTogK88sPa3RV0+00dRxL1IENp9Q7/+vrG e7oebdW91csb4gT1yQHS+UQLuxsippwJKMg+W66JlKoVlPWNHUu5m9dCI5DcOa4= X-Google-Smtp-Source: AGHT+IGTAWGI1voqkTMjn2gIYEEJTU7/GErDE+jq8ITjtfWt5vaUbYn+bhb3Su6Je6dsCpv9c0kwAA== X-Received: by 2002:a0c:ec0c:0:b0:6d3:5274:f37e with SMTP id 6a1803df08f44-6d35274f42dmr81776906d6.40.1730477951529; Fri, 01 Nov 2024 09:19:11 -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 af79cd13be357-7b2f3a6fedcsm182877585a.78.2024.11.01.09.19.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 01 Nov 2024 09:19:11 -0700 (PDT) Date: Fri, 1 Nov 2024 12:19:08 -0400 From: Gregory Price To: Borislav Petkov Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org, linux-cxl@vger.kernel.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, hpa@zytor.com, rafael@kernel.org, lenb@kernel.org, david@redhat.com, osalvador@suse.de, gregkh@linuxfoundation.org, akpm@linux-foundation.org, rppt@kernel.org Subject: Re: [PATCH v5 2/3] x86: probe memory block size advisement value during mm init Message-ID: References: <20241101134706.1185-1-gourry@gourry.net> <20241101134706.1185-3-gourry@gourry.net> <20241101155147.GBZyT5E190IxnQMzaP@fat_crate.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241101155147.GBZyT5E190IxnQMzaP@fat_crate.local> X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: ADE2840012 X-Stat-Signature: ino36z7j5sibojqiwf99a4stgdbbe4mp X-Rspam-User: X-HE-Tag: 1730477924-660506 X-HE-Meta: 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 SKB7rFYo SKR5oqe491uv/Mdech7B9PuXguR6F4fNSMOoJKPwkJK8i4o3wQT+MIre+Wu/TZlw1fMjOTG7X1cnVqRQOoOsKXeuOhvHNmoUf2qA28xok+VTzVKgbPsE8fsDpMsvBdSm1DQZeA34iv0b9V3CGuE8m0g1/kzZhTz4EkgUP8ETP4HdGyrBOfta3tPc2A66nsfFSzKSHCUUQxeOoNstAZacL0TpvaFzvtOG76Om796PnZ+PQDzaxVYxuAQsDMVUlRpYqQ7+uCSZd55QjFQn0hZ9M5PmVZNyNdA/4XILUZfyW9GzGU5ddCJW7WyrBs+3f6w0mfZGxckDxvfDZgn0Tq5ZiRd5XXOOaqubKoc79ICPCky/v4vVysm51cULCHjNrZIBX0vvrXaLPl1M1/ZI0AnqPHZZyBw== 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 Fri, Nov 01, 2024 at 04:51:47PM +0100, Borislav Petkov wrote: > On Fri, Nov 01, 2024 at 09:47:04AM -0400, 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 > > Acked-by: David Hildenbrand > > --- > > arch/x86/mm/init_64.c | 15 ++++++++++----- > > 1 file changed, 10 insertions(+), 5 deletions(-) > > > > diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c > > index ff253648706f..f1a495e998ce 100644 > > --- a/arch/x86/mm/init_64.c > > +++ b/arch/x86/mm/init_64.c > > @@ -1452,16 +1452,21 @@ 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_advised_max_size(); > > + if (!bz) { > > bz = MAX_BLOCK_SIZE; > > - goto done; > > + if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) > > s/boot_cpu_has/cpu_feature_enabled/ > > while at it. > I don't personally understand the implications of this switch off hand, probably warrants a separate patch submission if you think it's important given the original logic is boot_cpu_has and I don't want to increase scope change here. ~Gregory > -- > Regards/Gruss, > Boris. > > https://people.kernel.org/tglx/notes-about-netiquette