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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: <20251020170615.1000819-1-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: <20251020170615.1000819-1-gourry@gourry.net> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: s-dRs10A0fZO1HqaGmd-l9ojCvlkJpUixAdQftDce0w_1760981047 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: 84xp6tcrdwwymq33jfm9jkg1yamndpob X-Rspamd-Queue-Id: 1F8821C000B X-Rspamd-Server: rspam06 X-Rspam-User: X-HE-Tag: 1760981049-40568 X-HE-Meta: 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 YsJt7frr 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 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 19:06, 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 target contiguous > allocation request as valid targets for allocation. > > Compaction `isolate_migrate_pages_block()` already expects requests > with hugepages to originate from alloc_contig, and hugetlb code also > does a migratable check when isolating in `folio_isolate_hugetlb()`. > > We add the migration check here to avoid calling compaction on a > region if we know migration is not possible at all. > > Suggested-by: David Hildenbrand > Signed-off-by: Gregory Price > --- > mm/page_alloc.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 600d9e981c23..e0760eafe032 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -7048,8 +7048,14 @@ 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)) { > + struct folio *folio = page_folio(page); > + > + /* Don't consider moving same size/larger pages */ > + if (!folio_test_hugetlb_migratable(folio) || > + (1 << folio_order(folio) >= nr_pages)) We have folio_nr_pages(). Do we really need the folio_hugetlb_migratable() check? > + return false; This code is completely racy. folio_nr_pages() should be fine AFAIKT (no VM_WARN_ON() etc), not sure about folio_test_hugetlb_migratable(). If it becomes a problem we could do a snapshot_page() to take a snapshot we can query. -- Cheers David / dhildenb