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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: F3D0380016 X-Rspamd-Server: rspam03 X-Stat-Signature: ch1wu98ztgyhusqgfqdocc11yowrgx3a X-Rspam-User: X-HE-Tag: 1766059688-955017 X-HE-Meta: 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 kVoVjqLQ /Q+Bud8Y6Sg/z2/aQknslrr9BmiMjfr1oraBZS1Kl8HmdgX9JFmTdlPyoy8i6pKxJ6yFYOh6vj3ZQvlx4W9mMsYDUYxlXlRyZ8+LaB0/lgAtDJ2d7URGVqyNaJGe/O/sYIaXM 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: >>>   +#define clear_flush_young_ptes clear_flush_young_ptes >>> +static inline int clear_flush_young_ptes(struct vm_area_struct *vma, >>> +                    unsigned long addr, pte_t *ptep, >>> +                    unsigned int nr) >>> +{ >>> +    if (likely(nr == 1)) >>> +        return __ptep_clear_flush_young(vma, addr, ptep); >> >> Bug: This is broken if core-mm tries to call this for nr=1 on a pte that is part >> of a contpte mapping. >> >> The similar fastpaths are here to prevent regressing the common small folio case. > > Thanks for catching this. I had considered this before, but I still missed it. > >> I guess here the best approach is (note no leading underscores): >> >>     if (likely(nr == 1)) >>         return ptep_clear_flush_young(vma, addr, ptep); > > However, I prefer to use pte_cont() to check it. Later, I plan to clean up the > ptep_clear_flush_young(). > >     if (nr == 1 && !pte_cont(__ptep_get(ptep)) >         return __ptep_clear_flush_young(vma, addr, ptep); Sure. That would follow the pattern in clear_young_dirty_ptes(). Please use the likely() hint as is done everywhere else: if (likely(nr == 1 && !pte_cont(__ptep_get(ptep)))) I notice that ptep_test_and_clear_young() and ptep_clear_flush_young() are both testing aginst pte_valid_cont(). These could probably be relaxed to pte_cont() since it is implicit the the pte must be valid?