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 581E148032F; Thu, 1 Oct 2026 20:00:07 +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=1790884808; cv=none; b=NSQCBZFGd+Ld65mIiijXCaxKzXPBiYylUScKIKkEoQLMuOd41onEcNBlCPFEgWVHCh2qslr12CkbiiZ0V6MPckXaUkieA62o5yyzdsOMELPF1BqHN1EQkDfDIxAUMWHJ20IIb1ZT0hQoX+XDSQ1ncNPFIwI4ltnpalP6uusJ6PI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790884808; c=relaxed/simple; bh=zb1R7HobGn88ciUClLb5RIW1uwuBPPcv0tRxElqSa6w=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=JILJAptGhQ9r1To2y8UfJh9affei/cgEk5Qk4pvuzRQIoPpDUMQCNmGFIocron+dDQ1idUohWkOxoDPbK+ZLzHyUHIr4irO6mXnbIevh/ygISSpCRpx4qx7hYGWLHebcCrdrTb+6RVDPOu7hZOYpBX8gR2EPEO1DbFpmorDKuaE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kQZzHCFH; 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="kQZzHCFH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6121F1F000FF; Thu, 1 Oct 2026 20:00:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790884806; bh=uiy9BQNoShvervfQY5IpdBiMD4LpkWUHwQvhiosijDI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=kQZzHCFHEP+TTv4mj08h4QAEiWuMu20ydvBhcWwogSrpmEJttpYxip+BdOYU5VzM/ S+rk0fYkz6Sp9nV1+lz0q5jjMZ5UZSbxnq5ARISEsxwDHaDY36Hb+Rn7b/5moOaK0Y vjYJcrbxE7raQQr8ptYJVOovN+ZALhSFAyEjrCorWd7jiGGwMVAlaphP7I2udxcVZb JrISR+IRXQq8L3Site0mF+aVmoCdkVFwmwGVq86Q7F3yu9u6Xq6GqkMrS131dDySl/ mC6SL4B3P49PASoEHa9ZyMbX3m0ceQ+FU19PsItK+eeU0VgKTlzXtH5s86d/Uoqm2k DDckkQTEX1Lug== Message-ID: Date: Thu, 1 Oct 2026 21:59:57 +0200 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 v8 3/4] kselftest: mm: integrate huge page checks To: Yeoreum Yun Cc: Andrew Morton , Lorenzo Stoakes , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , Kevin Brodsky , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260924-fix_split-v8-0-cba7359d882a@arm.com> <20260924-fix_split-v8-3-cba7359d882a@arm.com> <16f16e77-05ab-418e-ad06-8f48fb29375a@kernel.org> <3e03425b-7962-4c69-93aa-96168fd7168e@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 On 10/1/26 15:52, Yeoreum Yun wrote: >> On 9/29/26 12:01, Yeoreum Yun wrote: >>> >>> Okay. I'll change like below in next-spin: >>> >>> -------&<------- >>> >>> @@ -411,57 +400,78 @@ static bool check_huge_type(uint64_t categories, enum check_huge_type type) >>> return false; >>> } >>> >>> -static bool __check_pmd_huge(void *addr, size_t len, int nr_hpages, >>> - uint64_t hpage_size, enum check_huge_type type) >>> +static bool __check_huge(void *addr, size_t len, int nr_hpages, >>> + uint64_t hpage_size, enum check_huge_type type) >>> { >>> { >>> - int pagemap_fd; >>> + bool ret = false; >>> + int pagemap_fd, kpageflags_fd; >>> int nr_pmd_mappings = 0; >>> + uint64_t pmd_pagesize, scan_mapping_size; >>> uint64_t categories; >>> + unsigned long pfn; >>> + bool check_pmd_mapping, allow_nonpresent; >>> char *start = addr; >>> char *end = start + len; >>> >>> + pmd_pagesize = read_pmd_pagesize(); >>> + if (!pmd_pagesize) >>> + ksft_exit_fail_msg("reading PMD pagesize failed\n"); >>> + >>> + check_pmd_mapping = hpage_size == pmd_pagesize; >>> + scan_mapping_size = (nr_hpages > 0) ? hpage_size : psize(); >>> + /* Some mTHP tests check a partially populated PMD-sized range. */ >>> + allow_nonpresent = (uint64_t)nr_hpages * hpage_size < len; >>> + >>> pagemap_fd = open(PAGEMAP_PATH, O_RDONLY); >>> if (pagemap_fd < 0) >>> ksft_exit_fail_perror("open pagemap"); >>> >>> - for (; start < end; start += hpage_size) { >>> + kpageflags_fd = open(KPAGEFLAGS_PATH, O_RDONLY); >>> + if (kpageflags_fd < 0) >>> + ksft_exit_fail_perror("open kpageflags"); >>> + >>> + for (; start < end; start += scan_mapping_size) { >>> categories = pagemap_scan_get_categories(pagemap_fd, start); >>> - if (!(categories & PAGE_IS_HUGE)) >>> + pfn = pagemap_get_pfn(pagemap_fd, start); >>> + if (pfn == -1UL) { >>> + if (!allow_nonpresent) >>> + goto out; >>> continue; >>> - if (check_huge_type(categories, type)) >>> + } >>> + if (!check_huge_type(categories, type)) >>> + goto out; >>> + } >>> + >>> + if (!check_pmd_mapping) { >>> + ret = check_large_folios(pagemap_fd, kpageflags_fd, >>> + addr, len, nr_hpages, hpage_size); >>> + goto out; >>> + } >>> + >>> + for (start = addr; start < end; start += scan_mapping_size) { >>> + categories = pagemap_scan_get_categories(pagemap_fd, start); >>> + if (categories & PAGE_IS_HUGE) >>> nr_pmd_mappings++; >>> } >>> - close(pagemap_fd); >>> >>> - return nr_hpages == nr_pmd_mappings; >>> + if (nr_pmd_mappings != nr_hpages) >>> + goto out; >>> + ret = true; >>> + >>> +out: >>> + close(pagemap_fd); >>> + close(kpageflags_fd); >>> + return ret; >>> } >>> >> >> I'd leave existing __check_huge() mostly alone, and instead have an additional >> function that checks the type. >> >> Essentially a __check_type() or sth that we run after the large folio / pmd check. > > So, You mean like this? > > -------&<------- > > -enum check_huge_type { > - CHECK_HUGE_ANON, > - CHECK_HUGE_FILE, > +enum check_type { > + CHECK_TYPE_ANON, > + CHECK_TYPE_FILE, > }; > > -static bool check_huge_type(uint64_t categories, enum check_huge_type type) > +static bool __check_type(void *addr, size_t len, uint64_t page_size, > + bool allow_nonpresent, enum check_type type) As discussed off-list, maybe we can avoid the allow_nonpresent handling! -- Cheers, David