diff options
| author | David Hildenbrand <david@redhat.com> | 2025-08-15 16:54:55 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-09-14 02:55:05 +0300 |
| commit | 8cdc4d27019356b0304308eb799484c899b62a87 (patch) | |
| tree | 414259af7af5c19763f6f7fd98ee5cb5d6130a87 /include/linux | |
| parent | 1f1c061089dcd274befa0c76fb9f6e253a8368c0 (diff) | |
| download | linux-8cdc4d27019356b0304308eb799484c899b62a87.tar.xz | |
mm/huge_memory: respect MADV_COLLAPSE with PR_THP_DISABLE_EXCEPT_ADVISED
Let's allow for making MADV_COLLAPSE succeed on areas that neither have
VM_HUGEPAGE nor VM_NOHUGEPAGE when we have THP disabled unless explicitly
advised (PR_THP_DISABLE_EXCEPT_ADVISED).
MADV_COLLAPSE is a clear advice that we want to collapse.
Note that we still respect the VM_NOHUGEPAGE flag, just like
MADV_COLLAPSE always does. So consequently, MADV_COLLAPSE is now only
refused on VM_NOHUGEPAGE with PR_THP_DISABLE_EXCEPT_ADVISED,
including for shmem.
Link: https://lkml.kernel.org/r/20250815135549.130506-4-usamaarif642@gmail.com
Co-developed-by: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yafang <laoar.shao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/huge_mm.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 92ea0b9771fa..1ac0d06fb3c1 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -329,7 +329,7 @@ struct thpsize { * through madvise or prctl. */ static inline bool vma_thp_disabled(struct vm_area_struct *vma, - vm_flags_t vm_flags) + vm_flags_t vm_flags, bool forced_collapse) { /* Are THPs disabled for this VMA? */ if (vm_flags & VM_NOHUGEPAGE) @@ -343,6 +343,12 @@ static inline bool vma_thp_disabled(struct vm_area_struct *vma, */ if (vm_flags & VM_HUGEPAGE) return false; + /* + * Forcing a collapse (e.g., madv_collapse), is a clear advice to + * use THPs. + */ + if (forced_collapse) + return false; return mm_flags_test(MMF_DISABLE_THP_EXCEPT_ADVISED, vma->vm_mm); } |