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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: 8E4E912000F X-Stat-Signature: sbd8gnm3jyfuwiytridozph8wtzr3jz8 X-HE-Tag: 1720105529-108702 X-HE-Meta: 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 7XxWuRZY 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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: Hey Ryan, On 2024/7/4 21:58, Ryan Roberts wrote: >>> Then for tmpfs, which doesn't support non-PMD-sizes yet, we just always use the >>> PMD-size control for decisions. >>> >>> I'm also really struggling with the concept of shmem_is_huge() existing along >>> side shmem_allowable_huge_orders(). Surely this needs to all be refactored into >>> shmem_allowable_huge_orders()? >> I understood. But now they serve different purposes: shmem_is_huge() will be >> used to check the huge orders for the top level, for*tmpfs* and anon shmem; >> whereas shmem_allowable_huge_orders() will only be used to check the per-size >> huge orders for anon shmem (excluding tmpfs now). However, as I plan to add mTHP >> support for tmpfs, I think we can perform some cleanups. >> >>>> +    /* Allow mTHP that will be fully within i_size. */ >>>> +    order = highest_order(within_size_orders); >>>> +    while (within_size_orders) { >>>> +        index = round_up(index + 1, order); >>>> +        i_size = round_up(i_size_read(inode), PAGE_SIZE); >>>> +        if (i_size >> PAGE_SHIFT >= index) { >>>> +            mask |= within_size_orders; >>>> +            break; >>>> +        } >>>> + >>>> +        order = next_order(&within_size_orders, order); >>>> +    } >>>> + >>>> +    if (vm_flags & VM_HUGEPAGE) >>>> +        mask |= READ_ONCE(huge_shmem_orders_madvise); >>>> + >>>> +    if (global_huge) >>> Perhaps I've misunderstood global_huge, but I think its just the return value >>> from shmem_is_huge()? But you're also using shmem_huge directly in this >> Yes. >> >>> function. I find it all rather confusing. >> I think I have explained why need these logics as above. Since mTHP support for >> shmem has just started (tmpfs is still in progress). I will make it more clear >> in the following patches. > OK as long as you have a plan for the clean up, that's good enough for me. Can I continue to push the following patch [1]? When other types of shmem mTHP are supported, we will perform cleanups uniformly. [1] https://lore.kernel.org/linux-mm/20240702023401.41553-1-libang.li@antgroup.com/ Thanks, Bang