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b=cy5LbhI1Ue9TWm1lcg9AHRjJXfcURt/N46ZWJcN5NJ/IqIqVCCTVYxQGeoiEioJ3P ZT7jHv1yZUTlmtxq0HfVd2pQ9zUd39CY1elvOxoIeoICBIvNH8gnyV86RzvKyD3xHv d3L2liZrssxOdkSB8zoZCPvgoYMJ1TVivkmORl00yvg8fH35IX0D0B1h3KHbfb8/je Pg3Oe7XgFJoe7rM/IzzOZ6ldArjT8pg8a1pBAHeJPkF6dFwlGPpNzrQVzTODOCyQZ4 ecJkLQwTGAyj+8cjl72zp0YTHcOE3Qrr7WomJTdlAwF3et5KyXF4OXgdXDi61OIqo6 PB63bKhoEKKuQ== Message-ID: <85e8ded9-a9eb-4663-9c96-93af60006fb6@kernel.org> Date: Thu, 5 Feb 2026 13:11:47 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH mm-new v6 2/5] mm: khugepaged: refine scan progress number To: Vernon Yang Cc: akpm@linux-foundation.org, lorenzo.stoakes@oracle.com, ziy@nvidia.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vernon Yang References: <20260201122554.1470071-1-vernon2gm@gmail.com> <20260201122554.1470071-3-vernon2gm@gmail.com> 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; format=flowed Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: C18DD40007 X-Stat-Signature: gyzi94fm55ihr7m8cpeshpfydtc44bug X-HE-Tag: 1770293512-459062 X-HE-Meta: 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 bP/MJ+d3 CI6iD0X2ztqaPnvRAm2o33007CDh1Yo8m4EojE/yV4CQVCpMMQNCFECFjnECvKgcxToiPti63NJlQbRGwWqZBWn+lhBpzu7Qc3YBffwr500p1c9SwYpYxrNOJ1k2JzhYwRQqE1MTx9Xpxm1p65RjGXnjZ2x5nTDoPIciwU2i+rLXsFZkTmxgreEkUxvduZL3cETwtlN2G0YpmfHFBdSuXa825Az2/Ai1os9aihCvUrjYy5cyf6ydnoqwOwVBD7yBHwP7rDSBiNfw7Mo/gRpbxg+PrYsMPoN6Me0Yn8Suazas8KhBbLuAsxa0iQw== 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 2/5/26 07:08, Vernon Yang wrote: > On Thu, Feb 5, 2026 at 5:35 AM David Hildenbrand (arm) wrote: >> >> [...] >> >>> + if (cur_progress) { >>> + if (_pte >= pte + HPAGE_PMD_NR) >>> + *cur_progress = HPAGE_PMD_NR; >>> + else >>> + *cur_progress = _pte - pte + 1; >> >> *cur_progress = max(_pte - pte + 1, HPAGE_PMD_NR); > > I guess, your meaning is "min(_pte - pte + 1, HPAGE_PMD_NR)", not max(). Yes! > >> ? >> >> It's still a bit nasty, though. >> >> Can't we just add one at the beginning of the loop and let the compiler >> optimize that? ;) > > I'm also worried that the compiler can't optimize this since the body of > the loop is complex, as with Dev's opinion [1]. Why do we even have to optimize this? :) Premature ... ? :) -- Cheers, David