From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DC6C93ACF0E for ; Mon, 9 Mar 2026 13:45:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773063952; cv=none; b=udYxkDsPNg1NHL/04Zn9rjxVlTUYVGdek4nYyalNwYM9UCN5mMdIwOwuWpazZlBO8MQ5VAX39U08SWWRZlzRJENevtydqNGCi5guoNDiMR1yGlg18+/JTnFaPtLXNrFjX2wmrNjzH2JDGBBy7BrzAgheAjx2v/rjsIZg4a5yDHA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773063952; c=relaxed/simple; bh=uJhVNt32IndBelFxb/TnWkfy5J8A3tuWwwNGBogcLSc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=JQta0jIXeCccLYcAyxheMxE3ZURyzd9SVXcknUdwlgpjoi3wjYMBUXfCV2hKFgySSXlLkQLODZy6RfHKA4oxJoWsD/23euN/g+s0k8cPMCEO6k7HjQzh0M5f/ri5m5m5N7QoK743ApbcBKbAmYdDL8IIAV/8Te6QNAVbUQnhg2w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=f+uB5+io; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="f+uB5+io" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E7D6CC2BC9E; Mon, 9 Mar 2026 13:45:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773063951; bh=uJhVNt32IndBelFxb/TnWkfy5J8A3tuWwwNGBogcLSc=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=f+uB5+ioxZ2uQUIYl3Oc1O86bfYtlfqKUyT18pDwStUjEAZx1x9m3kVkZb9pFnqAl LNlCZhd42Jjm8zM5AysYSUHz26XAiQoa5iSRYTSVeHP5pgOj9cw2Qof5jk1ydrhut6 YboNQL8470tawD40gNEm0uOAMY1fOqC+gY1Ly2sczhYaxyQe6bFaWO0DUN0FKQz9GY SFXF2fbINuhEwy14PERotM0MUtofd8SNsLoYNXaZj+t6DfbWNkylkjEBd8wXJdZ0lr opLi9yTow4uaBOeYOniL3XcGKcGH0QZiEDh5JnmEDMdTvCVxOtDcQaAwBrJ0jm4Xq4 YFtuw+/FHjj3g== Message-ID: <1b61cbcc-d062-4475-8763-e415e821fd14@kernel.org> Date: Mon, 9 Mar 2026 14:45:41 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 3/4] mm: huge_memory: refactor enabled_store() with change_enabled() To: Breno Leitao , Andrew Morton , Lorenzo Stoakes , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Mike Rapoport Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, usamaarif642@gmail.com, kas@kernel.org, kernel-team@meta.com, "Lorenzo Stoakes (Oracle)" References: <20260309-thp_logs-v4-0-926b9840083e@debian.org> <20260309-thp_logs-v4-3-926b9840083e@debian.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: <20260309-thp_logs-v4-3-926b9840083e@debian.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/9/26 12:07, Breno Leitao wrote: > Refactor enabled_store() to use a new change_enabled() helper. > Introduce a separate enum global_enabled_mode and > global_enabled_mode_strings[], mirroring the anon_enabled_mode > pattern from the previous commit. > > A separate enum is necessary because the global THP setting does > not support "inherit", only "always", "madvise", and "never". > Reusing anon_enabled_mode would leave a NULL gap in the string > array, causing sysfs_match_string() to stop early and fail to > match entries after the gap. > > The helper uses the same loop pattern as change_anon_orders(), > iterating over an array of flag bit positions and using > test_and_set_bit()/test_and_clear_bit() to track whether the state > actually changed. > > Signed-off-by: Breno Leitao > Reviewed-by: Lorenzo Stoakes (Oracle) > --- > mm/huge_memory.c | 63 ++++++++++++++++++++++++++++++++++++++++++-------------- > 1 file changed, 48 insertions(+), 15 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 2d5b05a416dab..be42a28da31d8 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -330,30 +330,63 @@ static const char * const anon_enabled_mode_strings[] = { > [ANON_ENABLED_NEVER] = "never", > }; > > +enum global_enabled_mode { > + GLOBAL_ENABLED_ALWAYS = 0, > + GLOBAL_ENABLED_MADVISE = 1, > + GLOBAL_ENABLED_NEVER = 2, > +}; > + > +static const char * const global_enabled_mode_strings[] = { > + [GLOBAL_ENABLED_ALWAYS] = "always", > + [GLOBAL_ENABLED_MADVISE] = "madvise", > + [GLOBAL_ENABLED_NEVER] = "never", > +}; > + > +static bool change_enabled(enum global_enabled_mode mode) I'd similarly call this something like "set_global_enabled_mode" -- Cheers, David