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To: Gregory Price , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com, akpm@linux-foundation.org, vbabka@suse.cz, surenb@google.com, mhocko@suse.com, jackmanb@google.com, hannes@cmpxchg.org, ziy@nvidia.com References: <20251020210816.1089910-1-gourry@gourry.net> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZoEEwEIAEQCGwMCF4ACGQEFCwkIBwICIgIG FQoJCAsCBBYCAwECHgcWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaJzangUJJlgIpAAKCRBN 3hD3AP+DWhAxD/9wcL0A+2rtaAmutaKTfxhTP0b4AAp1r/eLxjrbfbCCmh4pqzBhmSX/4z11 opn2KqcOsueRF1t2ENLOWzQu3Roiny2HOU7DajqB4dm1BVMaXQya5ae2ghzlJN9SIoopTWlR 0Af3hPj5E2PYvQhlcqeoehKlBo9rROJv/rjmr2x0yOM8qeTroH/ZzNlCtJ56AsE6Tvl+r7cW 3x7/Jq5WvWeudKrhFh7/yQ7eRvHCjd9bBrZTlgAfiHmX9AnCCPRPpNGNedV9Yty2Jnxhfmbv Pw37LA/jef8zlCDyUh2KCU1xVEOWqg15o1RtTyGV1nXV2O/mfuQJud5vIgzBvHhypc3p6VZJ lEf8YmT+Ol5P7SfCs5/uGdWUYQEMqOlg6w9R4Pe8d+mk8KGvfE9/zTwGg0nRgKqlQXrWRERv cuEwQbridlPAoQHrFWtwpgYMXx2TaZ3sihcIPo9uU5eBs0rf4mOERY75SK+Ekayv2ucTfjxr Kf014py2aoRJHuvy85ee/zIyLmve5hngZTTe3Wg3TInT9UTFzTPhItam6dZ1xqdTGHZYGU0O otRHcwLGt470grdiob6PfVTXoHlBvkWRadMhSuG4RORCDpq89vu5QralFNIf3EysNohoFy2A LYg2/D53xbU/aa4DDzBb5b1Rkg/udO1gZocVQWrDh6I2K3+cCs7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20251020210816.1089910-1-gourry@gourry.net> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: ZvKpfzBxgpYZBApmc3zTTi9OzUWSvGFE6_K2bXu8EmE_1761039051 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 4536F40010 X-Stat-Signature: 4mw9u3xfr89hb6bfdw1c66pitu5dikt3 X-HE-Tag: 1761039054-928577 X-HE-Meta: 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 4n5DYExj S9VMFhbSyTvuwgvA4HtWnqMEuuulKG8/Y2rozBb6zcMpLKPGUC+Et0rZWf9DWpxMeIyo6bkLXXqL76EShCEVgzYffDd6KVbjJTb6MgZgNfc1a/nKxBIUnp9aK+u/EFHO1PYUNpoDJV76J4916pNRR/JvVnHHZkJxbhzteoqfRTTrEN9ejSO+NEF6DCDzl5Z3/ZpA8OR+3iv9+R3qzLKNVfY5AB81Ra7O76g26tqQlj/mKbO9OMhmHakq60+eZMZ4KI60VebvX5RYznTA4iq7TOWOYTx5ABLnHMXJfPy5B9nNZCKjpBnXDu4hNAF29P9I7PnczqiqYtG+pz+dYTp948Y/G6PpJRU9cLoYDnZUNTKWTPI7hgaXA8PROF5dZuEdFbTrb3saMrYaT4EnLC/ZsJ/IsLbxE5VGeuTEbi9QIwcrhZQxxm+CrDgEYsuZ6lPjnElcB2sjwfLlALzEKoOezXAtoDHgn9/ycv50o3ip+lt4HBKk= 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 20.10.25 23:08, Gregory Price wrote: > We presently skip regions with hugepages entirely when trying to do > contiguous page allocation. Instead, if hugepage migration is enabled, > consider regions with hugepages smaller than the requested allocation. > > Compaction `isolate_migrate_pages_block()` already expects requests Please, let's not talk about "compaction" here, it's just confusing to talk about compaction for something that is not compaction but uses some primitives (because not properly separated yet) Just say "isolate_migrate_pages_block() already expects ..." > with hugepages to originate from alloc_contig, and hugetlb code also > does a migratable check when isolating in `folio_isolate_hugetlb()`. > > Suggested-by: David Hildenbrand > Signed-off-by: Gregory Price > --- > mm/page_alloc.c | 15 +++++++++++++-- > 1 file changed, 13 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 600d9e981c23..da2e65bf63e3 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -7048,8 +7048,19 @@ static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn, > if (PageReserved(page)) > return false; > > - if (PageHuge(page)) > - return false; > + if (PageHuge(page)) { > + unsigned int order; > + > + if (!IS_ENABLED(CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION)) > + return false; > + > + /* Don't consider moving same size/larger pages */ > + page = compound_head(page); > + order = compound_order(page); > + if ((order >= MAX_PAGE_ORDER) || > + (nr_pages < (1 << order))) > + return false; This is roughly what we do in pageblock_skip_persistent(), just with a hardcoded pageblock size. I'm not sure about the MAX_PAGE_ORDER check, though. If an arch supports two hugetlb sizes that exceed MAX_PAGE_ORDER, it would not work as expected. Doesn't arm64 support that with cont-PMD vs. PUD hugetlb folios? MAX_FOLIO_ORDER would be better. -- Cheers David / dhildenb