From: Anthony Yznaga Date: Wed, 16 Jul 2025 01:26:09 +0000 (-0700) Subject: sparc64: remove hugetlb_free_pgd_range() X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d0813985a23c222989136d3156c2ccf91fa03e0e;p=thirdparty%2Flinux.git sparc64: remove hugetlb_free_pgd_range() Patch series "drop hugetlb_free_pgd_range()". For all architectures that support hugetlb except for sparc, hugetlb_free_pgd_range() just calls free_pgd_range(). It turns out the sparc implementation is essentially identical to free_pgd_range() and can be removed. Remove it and update free_pgtables() to treat hugetlb VMAs the same as others. This patch (of 3): The sparc implementation of hugetlb_free_pgd_range() is identical to free_pgd_range() with the exception of checking for and skipping possible leaf entries at the PUD and PMD levels. These checks are unnecessary because any huge pages have been freed and their PTEs cleared by the time page tables needed to map them are freed. While some huge page sizes do populate the page table with multiple PTEs, they are correctly cleared by huge_ptep_get_and_clear(). To verify this, libhugetlbfs tests were run for 64K, 8M, and 256M page sizes with an instrumented kernel on a qemu guest modified to support the 256M page size. The same tests were used to verify no regressions after applying this patch and were also run on x86 for both 2M and 1G page sizes. Link: https://lkml.kernel.org/r/20250716012611.10369-1-anthony.yznaga@oracle.com Link: https://lkml.kernel.org/r/20250716012611.10369-2-anthony.yznaga@oracle.com Signed-off-by: Anthony Yznaga Acked-by: Mike Rapoport (Microsoft) Acked-by: Oscar Salvador Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Andreas Larsson Cc: Anshuman Khandual Cc: Arnd Bergmann Cc: Christophe Leroy Cc: David Hildenbrand Cc: David S. Miller Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Muchun Song Cc: Oscar Salvador Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton --- diff --git a/arch/sparc/include/asm/hugetlb.h b/arch/sparc/include/asm/hugetlb.h index e7a9cdd498dca..d3bc16fbcbbd5 100644 --- a/arch/sparc/include/asm/hugetlb.h +++ b/arch/sparc/include/asm/hugetlb.h @@ -50,11 +50,6 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma, return changed; } -#define __HAVE_ARCH_HUGETLB_FREE_PGD_RANGE -void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr, - unsigned long end, unsigned long floor, - unsigned long ceiling); - #include #endif /* _ASM_SPARC64_HUGETLB_H */ diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c index 80504148d8a5b..4b9431311e059 100644 --- a/arch/sparc/mm/hugetlbpage.c +++ b/arch/sparc/mm/hugetlbpage.c @@ -295,122 +295,3 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, return entry; } - -static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd, - unsigned long addr) -{ - pgtable_t token = pmd_pgtable(*pmd); - - pmd_clear(pmd); - pte_free_tlb(tlb, token, addr); - mm_dec_nr_ptes(tlb->mm); -} - -static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud, - unsigned long addr, unsigned long end, - unsigned long floor, unsigned long ceiling) -{ - pmd_t *pmd; - unsigned long next; - unsigned long start; - - start = addr; - pmd = pmd_offset(pud, addr); - do { - next = pmd_addr_end(addr, end); - if (pmd_none(*pmd)) - continue; - if (is_hugetlb_pmd(*pmd)) - pmd_clear(pmd); - else - hugetlb_free_pte_range(tlb, pmd, addr); - } while (pmd++, addr = next, addr != end); - - start &= PUD_MASK; - if (start < floor) - return; - if (ceiling) { - ceiling &= PUD_MASK; - if (!ceiling) - return; - } - if (end - 1 > ceiling - 1) - return; - - pmd = pmd_offset(pud, start); - pud_clear(pud); - pmd_free_tlb(tlb, pmd, start); - mm_dec_nr_pmds(tlb->mm); -} - -static void hugetlb_free_pud_range(struct mmu_gather *tlb, p4d_t *p4d, - unsigned long addr, unsigned long end, - unsigned long floor, unsigned long ceiling) -{ - pud_t *pud; - unsigned long next; - unsigned long start; - - start = addr; - pud = pud_offset(p4d, addr); - do { - next = pud_addr_end(addr, end); - if (pud_none_or_clear_bad(pud)) - continue; - if (is_hugetlb_pud(*pud)) - pud_clear(pud); - else - hugetlb_free_pmd_range(tlb, pud, addr, next, floor, - ceiling); - } while (pud++, addr = next, addr != end); - - start &= PGDIR_MASK; - if (start < floor) - return; - if (ceiling) { - ceiling &= PGDIR_MASK; - if (!ceiling) - return; - } - if (end - 1 > ceiling - 1) - return; - - pud = pud_offset(p4d, start); - p4d_clear(p4d); - pud_free_tlb(tlb, pud, start); - mm_dec_nr_puds(tlb->mm); -} - -void hugetlb_free_pgd_range(struct mmu_gather *tlb, - unsigned long addr, unsigned long end, - unsigned long floor, unsigned long ceiling) -{ - pgd_t *pgd; - p4d_t *p4d; - unsigned long next; - - addr &= PMD_MASK; - if (addr < floor) { - addr += PMD_SIZE; - if (!addr) - return; - } - if (ceiling) { - ceiling &= PMD_MASK; - if (!ceiling) - return; - } - if (end - 1 > ceiling - 1) - end -= PMD_SIZE; - if (addr > end - 1) - return; - - pgd = pgd_offset(tlb->mm, addr); - p4d = p4d_offset(pgd, addr); - do { - next = p4d_addr_end(addr, end); - if (p4d_none_or_clear_bad(p4d)) - continue; - hugetlb_free_pud_range(tlb, p4d, addr, next, floor, ceiling); - } while (p4d++, addr = next, addr != end); -}