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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: 88cmacxqaus4uyyddbu6xi5cnt985zd7 X-Rspamd-Queue-Id: 5450C40004 X-HE-Tag: 1785946899-321304 X-HE-Meta: U2FsdGVkX18tO8N+mXkamkARLooOl/umOnFKbqiNbUZyKwneLqrl5v7VczYBIQAMyqqhDlRWFGh+bM90SpOYTTDQwtOMH/QKKdevbQ80VBk599OgoYvjv9ubV7XjJWTXtz3fSVOIwJAuHDuMS2gR57e+Vo1uEVXJhxrglGNQf55PFTfpgmQ830a4I3mVVBQKkntl1ZyVe5LFjm6km0z8Khld2/qisHG7l8C1vj5w7+m3y6pK3tvoP6MBY6bLi39i7017v3CdiAYShzT7SyQfkC34pZEE2uW1v45mDl+1A81zXq8lbL4iuAS9gyhYP9tLqWEwLJdWlDi2eZQaBHKNIBJ/eRPRQHsNO3x6fxc3JvEokZsqjwo8r/lIIMa5JUFHD1XdulHFLNCcWuhmQLYj5mwuYqu3sc2GNvvPewnCozIcyq7d15KfYUFiiZftbyzgEGHJ2Dap71NrLL8nvsWZAKaU+xATquS1fj5BbXw6YIRQIW3HcZWsqntWrp91CmITpkeuy7d8nlpzj1ZfXafIg27uwAeloPNCxb/D4IOgWwI1pWEomBMjzLSmueoNp8qRzSNI8BObxtITIYUgAHrPj/Eo7egDS3pdbZ6+oxzZhI9fIIkVoXos7qN9PyEgBw0A8ggXns7fTPpKr106l/ihXD8MovY6aJ8D4Ic0IBzKBZ1uiAWNEsGjA8v71Qn28bT96k841rHRUMsrc5easIaRjdQy9vRIxCHXuV3PAa7eGcIwuXJ6dc7h0JWm0+a3+nwsgIq+rJ6MtCWaiqDlwiARCrh5Cbt+Fl/oVLnXR6wl6zSgLr+hIEBReUO+fWvjDzxjZpAMwjpH9J0j89a34TzZf4iwvxjQqYeZd4tCgQWhWACykQJxr25NyD9/BLOvLlrcMaAOfdOrr6aMAebc2BXpLVXbt3my5yatOi7YtPif8glduHeqpRFY/hPuj6ARaka8v3z33ZTUBIMDanhsOfb KpeGgIIB 36/acieWp7bCLDU3+djwoHdzj7fVS4yaxe+knO+Vg3b7L2G9kyHmQq8iLn+FY56L2r5dP0Mqvks7L4Yr10BKkYOOI/tmiJ5ROsavNDt/qE646mD3lDsxs2wiy4TYv6zCKvL1lkP2ZYo51XgUifRfR4HNyfQVtIYauOSpBABV6bLG0DC7GUswJIw7o6o+fRAaSDblm/JPJWXrW7NX0jTgVpS3AprPk9MkRRnnsLXNmz9UJmKQqBSbDmtNbZOqDpAEQRkgVqkbsfTZEFPBdneEUSjITyQbjypOD8cE5a97SwA1u7ush1fJ65qOwrJqlLTzmk0Q86E1nuiXfg9coSHncku4+RBpxEwwnAFgn36QHx3t6GTBUu7r0pFBnl+NmK76PiUJeH+jhb/neIZjUcCSKxVdMxjqTjAv6hZnqz+pn1ILCBEF/84upO3NRnjNuDHU43GGiDdfJcbNxKc2+nh9i2buGHzMWcKhGZwES Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Thanks for the quick feedback Lorenzo ! > So I think it should be something more like the attached. > > That way all the handling remains the same and the override is applied in > the right place plus smaps keeps working. LGTM, do you want me to respin a v2 with what's below ? or you'd rather send it yourself. C. > ----8<---- > From d6537260722c8741586e6295c8eea68d06087efa Mon Sep 17 00:00:00 2001 > From: "Lorenzo Stoakes (ARM)" > Date: Wed, 5 Aug 2026 11:35:13 +0100 > Subject: [PATCH] ideas > > --- > mm/huge_memory.c | 32 +++++++++++++++++++++++++++++--- > 1 file changed, 29 insertions(+), 3 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index abc65d608c23..5fa01364f089 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -111,6 +111,34 @@ static bool vma_is_special_huge(const struct vm_area_struct *vma) > return vma_test_any(vma, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT); > } > > +static bool should_obey_thp_file_tunables(const struct vm_area_struct *vma, > + bool forced_collapse) > +{ > + if (forced_collapse) > + return false; > + VM_WARN_ON_ONCE(vma_is_anonymous(vma)); > + /* Huge PFN mappings allocate no folios so the policy doesn't apply. */ > + if (vma_test(vma, VMA_PFNMAP_BIT) && vma->vm_ops->huge_fault) > + return false; > + return true; > +} > + > +static bool can_thp_collapse_file(const struct vm_area_struct *vma, > + vm_flags_t vm_flags, bool forced_collapse) > +{ > + /* Override THP tunables? */ > + if (!should_obey_thp_file_tunables(vma, forced_collapse)) > + return true; > + /* THP=always? */ > + if (hugepage_global_always()) > + return true; > + /* THP=madvise? */ > + if (!hugepage_global_enabled()) > + return false; > + /* Has VMA had madvise(..., MADV_HUGEPAGE) applied to it? */ > + return vm_flags & VM_HUGEPAGE; > +} > + > unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma, > vm_flags_t vm_flags, > enum tva_type type, > @@ -188,9 +216,7 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma, > * Enforce THP collapse requirements as necessary. Anonymous vmas > * were already handled in thp_vma_allowable_orders(). > */ > - if (!forced_collapse && > - (!hugepage_global_enabled() || (!(vm_flags & VM_HUGEPAGE) && > - !hugepage_global_always()))) > + if (!can_thp_collapse_file(vma, vm_flags, forced_collapse)) > return 0; > > /* > -- > 2.55.0 >