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(p200300cbc721a0007426f6b482a3c6ab.dip0.t-ipconnect.de. [2003:cb:c721:a000:7426:f6b4:82a3:c6ab]) by smtp.gmail.com with ESMTPSA id j14-20020a05600c190e00b0040b3525428bsm5704150wmq.2.2023.11.24.09.48.51 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 24 Nov 2023 09:48:52 -0800 (PST) Message-ID: Date: Fri, 24 Nov 2023 18:48:50 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RESEND PATCH v7 09/10] selftests/mm/cow: Generalize do_run_with_thp() helper To: Ryan Roberts , Andrew Morton , Matthew Wilcox , Yin Fengwei , Yu Zhao , Catalin Marinas , Anshuman Khandual , Yang Shi , "Huang, Ying" , Zi Yan , Luis Chamberlain , Itaru Kitayama , "Kirill A. Shutemov" , John Hubbard , David Rientjes , Vlastimil Babka , Hugh Dickins , Kefeng Wang Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20231122162950.3854897-1-ryan.roberts@arm.com> <20231122162950.3854897-10-ryan.roberts@arm.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; 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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <20231122162950.3854897-10-ryan.roberts@arm.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 667A1A000A X-Rspam-User: X-Stat-Signature: d1kkzrfqwrh97d9mtpjbb5ks9kf97o8i X-Rspamd-Server: rspam03 X-HE-Tag: 1700848138-582840 X-HE-Meta: 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 ibukqoW6 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 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 22.11.23 17:29, Ryan Roberts wrote: > do_run_with_thp() prepares (PMD-sized) THP memory into different states > before running tests. With the introduction of small-sized THP, we would > like to reuse this logic to also test those smaller THP sizes. So let's > add a size parameter which tells the function what size THP it should > operate on. > > A separate commit will utilize this change to add new tests for > small-sized THP, where available. > > Signed-off-by: Ryan Roberts > --- > tools/testing/selftests/mm/cow.c | 146 +++++++++++++++++-------------- > 1 file changed, 79 insertions(+), 67 deletions(-) > > diff --git a/tools/testing/selftests/mm/cow.c b/tools/testing/selftests/mm/cow.c > index 7324ce5363c0..d03c453cfd5c 100644 > --- a/tools/testing/selftests/mm/cow.c > +++ b/tools/testing/selftests/mm/cow.c > @@ -32,7 +32,7 @@ > > static size_t pagesize; > static int pagemap_fd; > -static size_t thpsize; > +static size_t pmdsize; > static int nr_hugetlbsizes; > static size_t hugetlbsizes[10]; > static int gup_fd; > @@ -734,14 +734,14 @@ enum thp_run { > THP_RUN_PARTIAL_SHARED, > }; > > -static void do_run_with_thp(test_fn fn, enum thp_run thp_run) > +static void do_run_with_thp(test_fn fn, enum thp_run thp_run, size_t size) Nit: can we still call it "thpsize" in this function? That makes it clearer IMHO and avoids most renaming. > { > char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED; > - size_t size, mmap_size, mremap_size; > + size_t mmap_size, mremap_size; > int ret; > > - /* For alignment purposes, we need twice the thp size. */ > - mmap_size = 2 * thpsize; > + /* For alignment purposes, we need twice the requested size. */ > + mmap_size = 2 * size; > mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, > MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); > if (mmap_mem == MAP_FAILED) { > @@ -749,36 +749,40 @@ static void do_run_with_thp(test_fn fn, enum thp_run thp_run) > return; > } > > - /* We need a THP-aligned memory area. */ > - mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); > + /* We need to naturally align the memory area. */ > + mem = (char *)(((uintptr_t)mmap_mem + size) & ~(size - 1)); > > - ret = madvise(mem, thpsize, MADV_HUGEPAGE); > + ret = madvise(mem, size, MADV_HUGEPAGE); > if (ret) { > ksft_test_result_fail("MADV_HUGEPAGE failed\n"); > goto munmap; > } > > /* > - * Try to populate a THP. Touch the first sub-page and test if we get > - * another sub-page populated automatically. > + * Try to populate a THP. Touch the first sub-page and test if > + * we get the last sub-page populated automatically. > */ > mem[0] = 0; > - if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) { > + if (!pagemap_is_populated(pagemap_fd, mem + size - pagesize)) { > ksft_test_result_skip("Did not get a THP populated\n"); > goto munmap; > } Yes! I have a patch lying around here that does that same. :) I guess there is no need to set MADV_NOHUGEPAGE on the remainder of the mmap'ed are: Assume we want a 64KiB thp. We mmap'ed 128KiB. If we get a reasonably aligned area, we might populate a 128KiB THP. But I assume the MADV_HUGEPAGE will in all configurations properly create a separate 64KiB VMA and we'll never get 128 KiB populated. So this should work reliably. > - memset(mem, 0, thpsize); > + memset(mem, 0, size); > > - size = thpsize; > switch (thp_run) { > case THP_RUN_PMD: > case THP_RUN_PMD_SWAPOUT: > + if (size != pmdsize) { > + ksft_test_result_fail("test bug: can't PMD-map size\n"); > + goto munmap; > + } Maybe rather "assert()" because that's a real BUG in the test? [...] > + pmdsize = read_pmd_pagesize(); > + if (pmdsize) > + ksft_print_msg("[INFO] detected PMD-mapped THP size: %zu KiB\n", Maybe simply: "detected PMD size". Zes, we read it via the THP interface, but that shouldn't matter much. -- Cheers, David / dhildenb