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Tsirkin" Cc: linux-kernel@vger.kernel.org, Andrew Morton , Vlastimil Babka , Brendan Jackman , Michal Hocko , Suren Baghdasaryan , Jason Wang , Andrea Arcangeli , linux-mm@kvack.org, virtualization@lists.linux.dev, Johannes Weiner , Zi Yan , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , "Matthew Wilcox (Oracle)" , Muchun Song , Oscar Salvador , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Ying Huang , Alistair Popple , Hugh Dickins , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , linux-fsdevel@vger.kernel.org References: <9dd9deabd42801f3c344326991d1431c3d8db39d.1776808210.git.mst@redhat.com> <20260422171315-mutt-send-email-mst@kernel.org> <20260423074433-mutt-send-email-mst@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 7DF41C0013 X-Stat-Signature: jzpk7xkpphppsjs3qphcnpkciguax377 X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1776953642-621571 X-HE-Meta: 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 IvPYh2xC F7JX8zx5LQ0sb5vHdLdlEG4aPxp1VMaRuWZMMf5utycKkWlAuXLjYXlpWvshjFvsKvDAzBnkEAooahCie2zUkaMEopGQQPt73XWeiDcn+W+oQU3HhEaf73qVGsgD/WjyBRdZ7NcbYfcLC6RGqGA7hEqJiVYdQLXGuq08vzEtW18fSWPsLWdOrG3C99BXrH3Mm5V6+ZXG6b8o1ugeUJzAcHsb/K3QJ6VL5sE3ChwL+8bRsQJ1+/9rc7m18qPgGLBIPv0MLXjWGlk9qdx1wHhNUxDpogjdjkSBE1Zd0k3whBn8lvq5Ncn7zOMKN4z+7UUrSbukM2s2UVJoCjKwMEvLWZ48RYit4GrwpdOH3cjiXQx5BULGl9p2Mw5QG53JI7hOFtbaS Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/23/26 15:42, Gregory Price wrote: > On Thu, Apr 23, 2026 at 07:57:01AM -0400, Michael S. Tsirkin wrote: >> On Thu, Apr 23, 2026 at 11:46:56AM +0200, David Hildenbrand (Arm) wrote: >> >> Changes we have to add: 8 changes >> Rename 4 existing APIs adding _user: __alloc_pages, >> __folio_alloc, folio_alloc_mpol, __alloc_frozen_pages + add >> 4 wrapper macros/inlines in gfp.h that forward to the _user variants with >> USER_ADDR_NONE. Roughly 6-8 lines of boilerplate per API. >> > > This is essentially what i was proposing. > > The result would be more external surface to the buddy (at least 2 maybe > more functions, plus all the _noprof stuff and a bunch of other things). We probably wouldn't need prof stuff if all we care about is vma_alloc_folio() that will only be calling _noprof internally. > > And then all the callers have to be updated anywhere, and not make it > any harder to mess up. You either have > > old_interface(..., user_addr); > /* Churn everything using the old interface */ > > or > > __internal(..., user_addr) { } > > old_interface(...) { > __internal(..., NO_USER_ADDR); > } > > new_interface(..., user_addr) { > __internal(..., user_addr); > } > > /* > * Update some callsites to use new_interface() > * mostly a bunch of _mpol() functions but some others > */ > > but someone could still just as easily do > > old_interface(); > /* don't fall folio_zero_user() - Bug! */ > > So it's not like this makes things any harder to mess up. Right. Looking at the patch, there would already be less churn if folio_alloc_mpol() __alloc_frozen_pages_noprof() __alloc_pages() post_alloc_hook() Would have simple wrappers. hugetlb calls __alloc_frozen_pages(). That's rather nasty, given that it wants to allocate a frozen folio. alloc_hugetlb_folio() already consumes vma+addr. alloc_buddy_hugetlb_folio_with_mpol() already consumes vma+addr. Maybe we could forward the vma+addr here and call a vma_alloc_froze_folio() if we have a VMA+addr to have a clean interface. But really, that hugetlb code is rather messy. I'd vote for leaving hugetlb alone on a v1, and focusing on non-hugetlb first. -- Cheers, David