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That doesn't make sense, right? >>>> >>>> That's what I am saying: if there could be large folios in there, then >>>> let's tell the world. >>>> >>>> Getting in a scenario where the mapping claims to not support large >>>> folios, but then we have large folios in there is inconsistent, not? >>>> >>>> [...] >>>> >>>>> >>>>> For the current anonymous shmem (tmpfs is already clear, no questions= ), >>>>> I don=E2=80=99t think there will be any "will never have/does never a= llow" >>>>> cases, because it can be changed dynamically via the sysfs interfaces= . >>>> >>>> Right. It's about non-anon shmem with huge=3Doff. >>>> >>>>> >>>>> If we still want that logic, then for anonymous shmem we can treat it= as >>>>> always "might have large folios". >>> >>> OK. To resolve the confusion about 1, the logic should be changed as >>> follows. Does that make sense to you? >>> >>> if (sbinfo->huge || (sb->s_flags & SB_KERNMOUNT)) >>> =C2=A0=C2=A0=C2=A0=C2=A0mapping_set_large_folios(inode->i_mapping); >> >> I think that's better. > > Thanks for your valuable input. > > But has Willy says, maybe we can just >> unconditionally set it and have it even simpler. > > However, for tmpfs mounts, we should still respect the 'huge=3D' mount op= tion. See commit 5a90c155defa ("tmpfs: don't enable large folios if not sup= ported"). Is it possible to get sbinfo->huge during tmpfs=E2=80=99s folio allocation = time, so that even if all tmpfs has mapping_set_large_folios() but sbinfo->huge can still decide whether huge page will be allocated for a tmpfs? Best Regards, Yan, Zi