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charset="US-ASCII"; x-default=true X-Rspamd-Queue-Id: 5545E14000A X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: 61yfzwfu5d8gjkfcsymzm1shu9wcz3yh X-HE-Tag: 1770675288-251873 X-HE-Meta: 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 czUAfNJS tEJRHXAPdem9CA+ZXi2wCTubAB9Em3+PiTf7vYpxwQ0J9a0IAQwr7hngcnwWpNk4Z7DlXDxV3BxjHr1UcXVcGN5tap4pgrLmi/ZL75eIb+USA5YBQj+4KK86xzw3CmJ6PaRHThhRQvNp1m9FsvlJF9Za7b175YGuQIkdIamjh0kBfrAgDoVlRn7bowuqR1z0UN5SUQxUkPMf0Hm/dTXCWmkac7HmLaL+N+OhWTfYkGIFFTh2ilRUGw4uNfQoz1F/MQYTYbJ/C0NCEtjcBLuWVhD4Zmg== 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: 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 v6.19, but I tested it on v6.19-rc8+. 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 (11): docs: tmpfs: remove implementation detail reference mm: introduce pgtable_has_pmd_leaves() drivers: dax: use pgtable_has_pmd_leaves() drivers: i915 selftest: 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 +- .../gpu/drm/i915/gem/selftests/huge_pages.c | 4 +++- drivers/nvdimm/pfn_devs.c | 6 ++++-- include/linux/huge_mm.h | 7 ------- include/linux/pgtable.h | 11 ++++++++-- init/main.c | 1 + mm/debug_vm_pgtable.c | 20 +++++++++---------- mm/huge_memory.c | 13 ++++++------ mm/memory.c | 10 +++++++++- mm/shmem.c | 11 +++++----- 21 files changed, 74 insertions(+), 60 deletions(-) -- 2.53.0