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charset="US-ASCII"; x-default=true X-Rspamd-Queue-Id: 8AC18180003 X-Stat-Signature: y7w8pqgcihiyca4z36dabu6af6osrge1 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1775680398-536074 X-HE-Meta: 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 DMM2wQb8 H0OvFPq2c6jdNiDM= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Today, if an architecture implements has_transparent_hugepage() and the CPU lacks support for PMD-sized pages, the THP code disables all THP, including mTHP. In addition, the kernel lacks a well defined API to check for PMD-sized page support. It currently relies on has_transparent_hugepage() and thp_disabled_by_hw(), but they are not well defined and are tied to THP support. This series addresses both issues by introducing a new well defined API to query PMD-sized page support: pgtable_has_pmd_leaves(). Using this new helper, we ensure that mTHP remains enabled even when the architecture or CPU doesn't support PMD-sized pages. Thanks to David Hildenbrand for suggesting this improvement and for providing guidance (all bugs and misconceptions are mine). This applies to Linus tree bfe62a454542 ("Merge tag 'soc-fixes-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc"). v3 -- - Rebased on top of latest Linus tree - Removed i915 patch as driver dropped has_transparent_hugepage() usage - Moved init_arch_has_pmd_leaves() call in start_kernel() to avoid conflict with early_param handlers clearing CPU feature flags - Fixed build error with CONFIG_MMU=n (kernel test robot) - Fixed huge_anon_orders_inherit default setting when !pgtable_pmd_leaves() (Baolin) - Small commit changelog improvements v2 -- - Added support for always enabling mTHPs for shmem (Baolin) - Improved commits changelog & added reviewed-by v1 -- - Call init_arch_has_pmd_leaves() from start_kernel() - Keep pgtable_has_pmd_leaves() calls tied to CONFIG_TRANSPARENT_HUGEPAGE (David) - Clear PUD_ORDER when clearing PMD_ORDER (David) - Small changelog improvements (David) - Rebased on top of latest mm-new Luiz Capitulino (10): docs: tmpfs: remove implementation detail reference mm: introduce pgtable_has_pmd_leaves() drivers: dax: use pgtable_has_pmd_leaves() drivers: nvdimm: use pgtable_has_pmd_leaves() mm: debug_vm_pgtable: use pgtable_has_pmd_leaves() mm: shmem: drop has_transparent_hugepage() usage treewide: rename has_transparent_hugepage() to arch_has_pmd_leaves() mm: replace thp_disabled_by_hw() with pgtable_has_pmd_leaves() mm: thp: always enable mTHP support mm: thp: x86: cleanup PSE feature bit usage Documentation/filesystems/tmpfs.rst | 5 ++--- arch/mips/include/asm/pgtable.h | 4 ++-- arch/mips/mm/tlb-r4k.c | 4 ++-- arch/powerpc/include/asm/book3s/64/hash-4k.h | 2 +- arch/powerpc/include/asm/book3s/64/hash-64k.h | 2 +- arch/powerpc/include/asm/book3s/64/pgtable.h | 10 +++++----- arch/powerpc/include/asm/book3s/64/radix.h | 2 +- arch/powerpc/mm/book3s64/hash_pgtable.c | 4 ++-- arch/s390/include/asm/pgtable.h | 4 ++-- arch/x86/include/asm/pgtable.h | 6 ------ arch/x86/include/asm/pgtable_32.h | 6 ++++++ drivers/dax/dax-private.h | 2 +- drivers/nvdimm/pfn_devs.c | 6 ++++-- include/linux/huge_mm.h | 7 ------- include/linux/pgtable.h | 19 ++++++++++++++++-- init/main.c | 1 + mm/debug_vm_pgtable.c | 20 +++++++++---------- mm/huge_memory.c | 15 +++++++------- mm/memory.c | 10 +++++++++- mm/shmem.c | 11 +++++----- 20 files changed, 80 insertions(+), 60 deletions(-) -- 2.53.0