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charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.243] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm100001.china.huawei.com (7.185.36.93) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: B9891120009 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: ijibck7yoeu3bdgex7qeyigubsc8hnza X-HE-Tag: 1699514940-860307 X-HE-Meta: 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 Tl6R5CJ/ VJXqjOEox3Oxj+/ezxE9+q04uDiG00TXGAZZzLMlz3NPei4iTRYy5fYF733HaXesYvL+6vptt92Gv3F7jBxP5R1yjvNK0t+mZHGmIkfm7d87kVRLJqJ3UsH/Yje0AANiUXdeeqRX0cNqwm8JTNLzrsVxKojdGfT4BKeJTh+kAVtoKIcAtHqRgEyEZrV4MP7/WPklEaTZKFkhC0+GmiGSKzMGL1A== 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 2023/11/8 21:59, Matthew Wilcox wrote: > On Wed, Nov 08, 2023 at 09:40:09AM +0800, Kefeng Wang wrote: >> >> >> On 2023/11/7 22:24, Matthew Wilcox wrote: >>> On Tue, Nov 07, 2023 at 09:52:11PM +0800, Kefeng Wang wrote: >>>> struct page *ksm_might_need_to_copy(struct page *page, >>>> - struct vm_area_struct *vma, unsigned long address) >>>> + struct vm_area_struct *vma, unsigned long addr) >>>> { >>>> struct folio *folio = page_folio(page); >>>> struct anon_vma *anon_vma = folio_anon_vma(folio); >>>> - struct page *new_page; >>>> + struct folio *new_folio; >>>> - if (PageKsm(page)) { >>>> - if (page_stable_node(page) && >>>> + if (folio_test_ksm(folio)) { >>>> + if (folio_stable_node(folio) && >>>> !(ksm_run & KSM_RUN_UNMERGE)) >>>> return page; /* no need to copy it */ >>>> } else if (!anon_vma) { >>>> return page; /* no need to copy it */ >>>> - } else if (page->index == linear_page_index(vma, address) && >>>> + } else if (page->index == linear_page_index(vma, addr) && >>> >>> Hmm. page->index is going away. What should we do here instead? >> >> Do you mean to replace page->index to folio->index, or kill index from >> struct page? > > I'm asking you what we should do. > > Tail pages already don't have a valid ->index (or ->mapping). > So presumably we can't see a tail page here today. But will we in future? I think we could replace page->index to page_to_pgoff(page). > > Just to remind you, the goal here is: > > struct page { > unsigned long memdesc; > }; > Get your point, that will be great. > so folios will be the only thing that have a ->index. I haven't looked > at this code; I know nothing about it. But you're changing it, so you > must have some understanding of it. >