From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 652C21DFFD for ; Fri, 31 Jul 2026 09:17:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785489453; cv=none; b=IJ85VS8TINo8wqbraCo0Iq8fgt0doE3TvLfFu13JYBbsna+8ng0tUjpgfGik/hPxApAQ08QTcpkZQN0QMKuCEV9BEuSFNcvKbeBoASuwHD68GYM+omoLYbKJ4vbh5msVssHFyh6/zoohNrRtYissdrpu5dijPwd3Wqkb5LTbmxA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785489453; c=relaxed/simple; bh=ETsAF6YHjL8uUDxCDN+lcKhsiPyhc8pwr29n5cxxUS4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UpIkxEvsbeX6vC+vjSSSQVL2zAIDJ6cThCr9jIoiZiH3NikiS0wwo0li44THsBVghG8CWmdXQkI6qgd1fKdzlCV4baTfbWn72dXf6G6T9qqBCTqXmFbp8pLoeFwwrpnH2+KG52TjfucRpTkWnFk3nPNnzpiE1Q7jrbvtiMX9jDw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HPz9HUnd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HPz9HUnd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 633691F000E9; Fri, 31 Jul 2026 09:17:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785489452; bh=SmXHxm/S8gWAcFTPx9bcFZXCiUJzwFzL8tV4kp0WIxU=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=HPz9HUnd+RzfuNqF4BxNb0nf8/PabOFpkZi9AJIOfsuvqKyxT30y6mUyqxgyCYHFM uqc0pOT5Y9b7sAYZWt6oUoR0VVwHAfSk2nlCmbHIWTrIOqMx+cT6ne8RCsWfuZRS9F GnJ1gkId/DRMKHTI4gNwt2umOzD5HUuF7gNcuNS/Zc5fSrAW4jF19EU6Ni/SDixRor m2nRC6k2xKe9tFMXKxPpAW+9yhKKc0JD0lOPfL/dbLASYEHYavC/1dQJWHYbu6KfHp c9rt5F70+bY+sm0lRsq9YaKj1Vo8CjKIRAOLJ/gNs0gnn1NVpYA6vO3QCIFqA00+3z jhVgVxUKa+b4g== Message-ID: <33b55954-71e7-4e8d-868a-0440c1b28ae8@kernel.org> Date: Fri, 31 Jul 2026 11:17:24 +0200 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/2] mm/ksm: fix advisor_min_pages_to_scan description To: Jinjiang Tu , akpm@linux-foundation.org, xu.xin16@zte.com.cn, chengming.zhou@linux.dev, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, corbet@lwn.net, skhan@linuxfoundation.org, shr@devkernel.io, linux-mm@kvack.org, linux-doc@vger.kernel.org Cc: wangkefeng.wang@huawei.com, sunnanyong@huawei.com References: <20260731083526.3953421-1-tujinjiang@huawei.com> <20260731083526.3953421-3-tujinjiang@huawei.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: <20260731083526.3953421-3-tujinjiang@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/31/26 10:35, Jinjiang Tu wrote: > Both Documentation/admin-guide/mm/ksm.rst and the comment next to the > variable definition in mm/ksm.c describe advisor_min_pages_to_scan as a > lower limit of the pages_to_scan parameter, but that is not how the > scan-time advisor actually uses it. commit 4e5fa4f5eff6 ("mm/ksm: add ksm > advisor") only uses it to initialize ksm_thread_pages_to_scan when the > scan-time advisor is enabled. This will mislead the users. > > The semantics of advisor_min_pages_to_scan was updated in the v2 patchset > [1], but the documention wasn't updated. s/documention/documentation/ > > Update the documentation and comment to match the semantics of > advisor_min_pages_to_scan. > > Link: https://lore.kernel.org/linux-mm/20231028000945.2428830-2-shr@devkernel.io/ [1] > Fixes: 0710f38ad26a ("mm/ksm: document ksm advisor and its sysfs knobs") > Fixes: 66790e9a735b ("mm/ksm: add sysfs knobs for advisor") Drop these. > Signed-off-by: Jinjiang Tu > --- > Documentation/admin-guide/mm/ksm.rst | 4 ++-- > mm/ksm.c | 2 +- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst > index c9f533b10f6f..c329ca747b8c 100644 > --- a/Documentation/admin-guide/mm/ksm.rst > +++ b/Documentation/admin-guide/mm/ksm.rst > @@ -183,8 +183,8 @@ advisor_target_scan_time > pages. The default value is 200 seconds. > > advisor_min_pages_to_scan > - specifies the lower limit of the ``pages_to_scan`` parameter of the > - scan time advisor. The default is 500. > + specifies the initial value of the ``pages_to_scan`` parameter of > + the scan time advisor. The default is 500. Makes sense. > > advisor_max_pages_to_scan > specifies the upper limit of the ``pages_to_scan`` parameter of the > diff --git a/mm/ksm.c b/mm/ksm.c > index 7d5b76478f0b..1e3a9c657a64 100644 > --- a/mm/ksm.c > +++ b/mm/ksm.c > @@ -342,7 +342,7 @@ static enum ksm_advisor_type ksm_advisor; > * Only called through the sysfs control interface: > */ > > -/* At least scan this many pages per batch. */ > +/* Initial number of pages to scan per batch when the scan-time advisor is enabled. */ > static unsigned long ksm_advisor_min_pages_to_scan = 500; "when the scan-time advisor is enabled" is clear from the variable name. So I'd shorten it to "Initial number of pages to scan per batch" -- Cheers, David