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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: E39B6120006 X-Rspam-User: X-Stat-Signature: wnxoi6phiqpx9gup7ankdwefzrnqpk7r X-HE-Tag: 1768210651-694689 X-HE-Meta: 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 P65qd/CE 3DTRVEDFoeAjcYx1fPH2BSgoFWtzmEFq5yFsKlIiNbtalLpmQP1nrdRnCuTN9ArIBgjUgKsmlz2wuGtf4Er5V7/rUMMhD8v2b3yHQQgsU+lw6qmT1YMSzJnUxDu/gTOr9GyiA9YvAFG54npbgDAY0O5jBSdcNESg+FdCzMiVZTUMROYCYeEx3BkhDp10oRb9kWbdyY+6Ioz5hKKJWI+6Bj5oQI1HeDf+UJuRm 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 09/01/2026 02:30, SeongJae Park wrote: > On Wed, 7 Jan 2026 16:48:39 +0000 Kevin Brodsky wrote: > >> FORCE_READ(*addr) ensures that the compiler will emit a load from >> addr. Several tests need to trigger such a load for every page in >> the range [addr, addr + len), ensuring that every page is faulted >> in, if it wasn't already. >> >> Introduce a new helper force_read_pages_in_range() that does exactly >> that and replace existing loops with a call to it. > Seems like a good cleanup to me. Thanks for having a look at this series! >> Some of those >> loops have a different step size, but reading from every page is >> appropriate in all cases. > So the test program's behavior is slightly be changed. I believe that > shouldn't be problem, but I'm not that familiar with the test code, so not very > sure. I'd like to listen voices from people more familiar with those. > > Meanwhile, I'm curious what do you think about making the helper function > receives the step size together, and let the callers just pass their current > step size. That's what I initially considered, but considering this discussion on v1 [1] this doesn't seem to be justified. In hugetlb-madvise, reading every page instead of every hugepage is unnecessary but still correct and the overhead should be negligible. In split_huge_page_test, I don't think there's any justification for reading every byte - the intention is to fault in pages, like all the other cases this patch touches. - Kevin [1] https://lore.kernel.org/all/a3ca6293-8f85-4489-a48e-eb8d0d3792c5@kernel.org/