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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: 0FB8C40014 X-Stat-Signature: 41ygmqwucs8i7e7ix59tz1cg6z8cfg4k X-HE-Tag: 1719825277-393102 X-HE-Meta: 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 gWoQdy+C u0G4uIfBhorfH3Snk5BGWnTEgKJs/CnAYAz5n2TV68SzfESCvElpZWeAq/Y3rqXWnl2roGWzIsRuDZkD4InSAjBGA4quWZ9Oldo33+FLsugFQk5pLkvQSBJI7RmbSyfDQbIt2z9hEGSZOWY+jhvZDcWmO9v3m6A25tMNX2cLwOWWXhguN8lJTpUUtNYkmOFQwSXPmVQcI0P15521/npjFrPdnO2E0XEkVYdOp 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 01/07/2024 09:57, David Hildenbrand wrote: > On 01.07.24 10:50, Ryan Roberts wrote: >> On 01/07/2024 09:48, David Hildenbrand wrote: >>> On 01.07.24 10:40, Ryan Roberts wrote: >>>> On 01/07/2024 09:33, Baolin Wang wrote: >>>>> >>>>> >>>>> On 2024/7/1 15:55, Ryan Roberts wrote: >>>>>> On 28/06/2024 11:49, Bang Li wrote: >>>>>>> After the commit 7fb1b252afb5 ("mm: shmem: add mTHP support for >>>>>>> anonymous shmem"), we can configure different policies through >>>>>>> the multi-size THP sysfs interface for anonymous shmem. But >>>>>>> currently "THPeligible" indicates only whether the mapping is >>>>>>> eligible for allocating THP-pages as well as the THP is PMD >>>>>>> mappable or not for anonymous shmem, we need to support semantics >>>>>>> for mTHP with anonymous shmem similar to those for mTHP with >>>>>>> anonymous memory. >>>>>>> >>>>>>> Signed-off-by: Bang Li >>>>>>> --- >>>>>>>     fs/proc/task_mmu.c      | 10 +++++++--- >>>>>>>     include/linux/huge_mm.h | 11 +++++++++++ >>>>>>>     mm/shmem.c              |  9 +-------- >>>>>>>     3 files changed, 19 insertions(+), 11 deletions(-) >>>>>>> >>>>>>> diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c >>>>>>> index 93fb2c61b154..09b5db356886 100644 >>>>>>> --- a/fs/proc/task_mmu.c >>>>>>> +++ b/fs/proc/task_mmu.c >>>>>>> @@ -870,6 +870,7 @@ static int show_smap(struct seq_file *m, void *v) >>>>>>>     { >>>>>>>         struct vm_area_struct *vma = v; >>>>>>>         struct mem_size_stats mss = {}; >>>>>>> +    bool thp_eligible; >>>>>>>           smap_gather_stats(vma, &mss, 0); >>>>>>>     @@ -882,9 +883,12 @@ static int show_smap(struct seq_file *m, void *v) >>>>>>>           __show_smap(m, &mss, false); >>>>>>>     -    seq_printf(m, "THPeligible:    %8u\n", >>>>>>> -           !!thp_vma_allowable_orders(vma, vma->vm_flags, >>>>>>> -               TVA_SMAPS | TVA_ENFORCE_SYSFS, THP_ORDERS_ALL)); >>>>>>> +    thp_eligible = !!thp_vma_allowable_orders(vma, vma->vm_flags, >>>>>>> +                        TVA_SMAPS | TVA_ENFORCE_SYSFS, THP_ORDERS_ALL); >>>>>>> +    if (vma_is_anon_shmem(vma)) >>>>>>> +        thp_eligible = >>>>>>> !!shmem_allowable_huge_orders(file_inode(vma->vm_file), >>>>>>> +                            vma, vma->vm_pgoff, thp_eligible); >>>>>> >>>>>> Afraid I haven't been following the shmem mTHP support work as much as I >>>>>> would >>>>>> have liked, but is there a reason why we need a separate function for shmem? >>>>> >>>>> Since shmem_allowable_huge_orders() only uses shmem specific logic to >>>>> determine >>>>> if huge orders are allowable, there is no need to complicate the >>>>> thp_vma_allowable_orders() function by adding more shmem related logic, making >>>>> it more bloated. In my view, providing a dedicated helper >>>>> shmem_allowable_huge_orders(), specifically for shmem, simplifies the logic. >>>> >>>> My point was really that a single interface (thp_vma_allowable_orders) >>>> should be >>>> used to get this information. I have no strong opinon on how the implementation >>>> of that interface looks. What you suggest below seems perfectly reasonable >>>> to me. >>> >>> Right. thp_vma_allowable_orders() might require some care as discussed in other >>> context (cleanly separate dax and shmem handling/orders). But that would be >>> follow-up cleanups. >> >> Are you planning to do that, or do you want me to send a patch? > > I'm planning on looking into some details, especially the interaction with large > folios in the pagecache. I'll let you know once I have a better idea what > actually should be done :) OK great - I'll scrub it from my todo list... really getting things done today :)