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To: Zi Yan , David Hildenbrand , linux-mm@kvack.org Cc: Matthew Wilcox , "Kirill A . Shutemov" , Mike Kravetz , Michal Hocko , John Hubbard , linux-kernel@vger.kernel.org References: <20210805190253.2795604-1-zi.yan@sent.com> From: Vlastimil Babka Message-ID: <0d374eed-cc52-a656-b338-1156782bdf7e@suse.cz> Date: Fri, 6 Aug 2021 18:32:15 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210805190253.2795604-1-zi.yan@sent.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/5/21 9:02 PM, Zi Yan wrote: > From: Zi Yan > > Hi all, > > This patchset add support for kernel boot time adjustable MAX_ORDER, so that > user can change the largest size of pages obtained from buddy allocator. It also > removes the restriction on MAX_ORDER based on SECTION_SIZE_BITS, so that > buddy allocator can merge PFNs across memory sections when SPARSEMEM_VMEMMAP is > set. It is on top of v5.14-rc4-mmotm-2021-08-02-18-51. > > Motivation > === > > This enables kernel to allocate 1GB pages and is necessary for my ongoing work > on adding support for 1GB PUD THP[1]. This is also the conclusion I came up with > after some discussion with David Hildenbrand on what methods should be used for > allocating gigantic pages[2], since other approaches like using CMA allocator or > alloc_contig_pages() are regarded as suboptimal. I see references [1] [2] etc but no list of links at the end, did you forgot to include?