Andrew, Please replace the patches in your mglru-maple branch with this set. It should be a drop in replacement for my patch range with the fixes into these patches. Adding the preallocation to work around the fs-reclaim LOCKDEP issue caused enough changes to the patches to warrant a respin. The last patch on the branch is still needed to fix vmscan after mglru is applied. ee4b1fc24f30 "mm/vmscan: Use VMA_ITERATOR in get_next_vma()" Here is the pretty cover letter you requested last time. ------------------------------------ The maple tree is an RCU-safe range based B-tree designed to use modern processor cache efficiently. There are a number of places in the kernel that a non-overlapping range-based tree would be beneficial, especially one with a simple interface. The first user that is covered in this patch set is the vm_area_struct, where three data structures are replaced by the maple tree: the augmented rbtree, the vma cache, and the linked list of VMAs in the mm_struct. The long term goal is to reduce or remove the mmap_sem contention. The tree has a branching factor of 10 for non-leaf nodes and 16 for leaf nodes. With the increased branching factor, it is significantly shorter than the rbtree so it has fewer cache misses. The removal of the linked list between subsequent entries also reduces the cache misses and the need to pull in the previous and next VMA during many tree alterations. This patch set is based on v5.18-rc2 git: https://github.com/oracle/linux-uek/tree/howlett/maple/20220426 v8 changes: - Added preallocations before any potential edits to the tree when holding the i_mmap_lock to avoid fs-reclaim issues on extreme memory pressure. - Fixed issue in mempolicy mas_for_each() loop. - Moved static definitions inside ifdef for DEBUG_MAPLE - Fixed compile warnings reported by build bots - Moved mas_dfs_preorder() to testing code - Changed __vma_adjust() to record the highest vma in case 6 instead of finding it twice. - Fixed locking issue in exit_mmap() - Fixed up from/s-o-b ordering v7: https://lore.kernel.org/linux-mm/20220404143501.2016403-8-Liam.Howlett@xxxxxxxxxx/ v6: https://lore.kernel.org/linux-mm/20220215143728.3810954-1-Liam.Howlett@xxxxxxxxxx/ v5: https://lore.kernel.org/linux-mm/20220202024137.2516438-1-Liam.Howlett@xxxxxxxxxx/ v4: https://lore.kernel.org/linux-mm/20211201142918.921493-1-Liam.Howlett@xxxxxxxxxx/ v3: https://lore.kernel.org/linux-mm/20211005012959.1110504-1-Liam.Howlett@xxxxxxxxxx/ v2: https://lore.kernel.org/linux-mm/20210817154651.1570984-1-Liam.Howlett@xxxxxxxxxx/ v1: https://lore.kernel.org/linux-mm/20210428153542.2814175-1-Liam.Howlett@xxxxxxxxxx/ Liam R. Howlett (45): radix tree test suite: add pr_err define radix tree test suite: add kmem_cache_set_non_kernel() radix tree test suite: add allocation counts and size to kmem_cache radix tree test suite: add support for slab bulk APIs radix tree test suite: add lockdep_is_held to header mips: rename mt_init to mips_mt_init Maple Tree: add new data structure lib/test_maple_tree: add testing for maple tree mm: start tracking VMAs with maple tree mm/mmap: use the maple tree in find_vma() instead of the rbtree. mm/mmap: use the maple tree for find_vma_prev() instead of the rbtree mm/mmap: use maple tree for unmapped_area{_topdown} kernel/fork: use maple tree for dup_mmap() during forking damon: Convert __damon_va_three_regions to use the VMA iterator mm: remove rb tree. mmap: change zeroing of maple tree in __vma_adjust() xen: use vma_lookup() in privcmd_ioctl_mmap() mm: optimize find_exact_vma() to use vma_lookup() mm/khugepaged: optimize collapse_pte_mapped_thp() by using vma_lookup() mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap() mm: use maple tree operations for find_vma_intersection() mm/mmap: use advanced maple tree API for mmap_region() mm: remove vmacache mm: convert vma_lookup() to use mtree_load() mm/mmap: move mmap_region() below do_munmap() mm/mmap: reorganize munmap to use maple states mm/mmap: change do_brk_munmap() to use do_mas_align_munmap() arm64: Change elfcore for_each_mte_vma() to use VMA iterator fs/proc/base: use maple tree iterators in place of linked list userfaultfd: use maple tree iterator to iterate VMAs ipc/shm: use VMA iterator instead of linked list bpf: remove VMA linked list mm/gup: use maple tree navigation instead of linked list mm/madvise: use vma_find() instead of vma linked list mm/memcontrol: stop using mm->highest_vm_end mm/mempolicy: use vma iterator & maple state instead of vma linked list mm/mprotect: use maple tree navigation instead of vma linked list mm/mremap: use vma_find_intersection() instead of vma linked list mm/msync: use vma_find() instead of vma linked list mm/oom_kill: use maple tree iterators instead of vma linked list mm/swapfile: use vma iterator instead of vma linked list riscv: use vma iterator for vdso mm: remove the vma linked list mm/mmap: drop range_has_overlap() function mm/mmap.c: pass in mapping to __vma_link_file() Matthew Wilcox (Oracle) (25): mm: add VMA iterator mmap: use the VMA iterator in count_vma_pages_range() proc: remove VMA rbtree use from nommu arm64: remove mmap linked list from vdso parisc: remove mmap linked list from cache handling powerpc: remove mmap linked list walks s390: remove vma linked list walks x86: remove vma linked list walks xtensa: remove vma linked list walks cxl: remove vma linked list walk optee: remove vma linked list walk um: remove vma linked list walk coredump: remove vma linked list walk exec: use VMA iterator instead of linked list fs/proc/task_mmu: stop using linked list and highest_vm_end acct: use VMA iterator instead of linked list perf: use VMA iterator sched: use maple tree iterator to walk VMAs fork: use VMA iterator mm/khugepaged: stop using vma linked list mm/ksm: use vma iterators instead of vma linked list mm/mlock: use vma iterator and instead of vma linked list mm/pagewalk: use vma_find() instead of vma linked list i915: use the VMA iterator nommu: remove uses of VMA linked list Documentation/core-api/index.rst | 1 + Documentation/core-api/maple_tree.rst | 218 + MAINTAINERS | 12 + arch/arm64/kernel/elfcore.c | 16 +- arch/arm64/kernel/vdso.c | 3 +- arch/mips/kernel/mips-mt.c | 4 +- arch/parisc/kernel/cache.c | 7 +- arch/powerpc/kernel/vdso.c | 6 +- arch/powerpc/mm/book3s32/tlb.c | 11 +- arch/powerpc/mm/book3s64/subpage_prot.c | 13 +- arch/riscv/kernel/vdso.c | 3 +- arch/s390/kernel/vdso.c | 3 +- arch/s390/mm/gmap.c | 6 +- arch/um/kernel/tlb.c | 14 +- arch/x86/entry/vdso/vma.c | 9 +- arch/x86/kernel/tboot.c | 2 +- arch/xtensa/kernel/syscall.c | 18 +- drivers/firmware/efi/efi.c | 2 +- drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 14 +- drivers/misc/cxl/fault.c | 45 +- drivers/tee/optee/call.c | 18 +- drivers/xen/privcmd.c | 2 +- fs/coredump.c | 34 +- fs/exec.c | 12 +- fs/proc/base.c | 5 +- fs/proc/internal.h | 2 +- fs/proc/task_mmu.c | 74 +- fs/proc/task_nommu.c | 45 +- fs/userfaultfd.c | 49 +- include/linux/maple_tree.h | 685 + include/linux/mm.h | 74 +- include/linux/mm_types.h | 43 +- include/linux/mm_types_task.h | 12 - include/linux/sched.h | 1 - include/linux/userfaultfd_k.h | 7 +- include/linux/vm_event_item.h | 4 - include/linux/vmacache.h | 28 - include/linux/vmstat.h | 6 - include/trace/events/maple_tree.h | 123 + include/trace/events/mmap.h | 71 + init/main.c | 2 + ipc/shm.c | 21 +- kernel/acct.c | 11 +- kernel/bpf/task_iter.c | 10 +- kernel/debug/debug_core.c | 12 - kernel/events/core.c | 3 +- kernel/events/uprobes.c | 9 +- kernel/fork.c | 58 +- kernel/sched/fair.c | 10 +- lib/Kconfig.debug | 17 +- lib/Makefile | 3 +- lib/maple_tree.c | 6964 +++ lib/test_maple_tree.c | 37854 ++++++++++++++++ mm/Makefile | 2 +- mm/damon/vaddr-test.h | 37 +- mm/damon/vaddr.c | 53 +- mm/debug.c | 14 +- mm/gup.c | 7 +- mm/huge_memory.c | 4 +- mm/init-mm.c | 4 +- mm/internal.h | 42 +- mm/khugepaged.c | 13 +- mm/ksm.c | 18 +- mm/madvise.c | 2 +- mm/memcontrol.c | 6 +- mm/memory.c | 33 +- mm/mempolicy.c | 56 +- mm/mlock.c | 34 +- mm/mmap.c | 2079 +- mm/mprotect.c | 7 +- mm/mremap.c | 22 +- mm/msync.c | 2 +- mm/nommu.c | 135 +- mm/oom_kill.c | 3 +- mm/pagewalk.c | 2 +- mm/swapfile.c | 4 +- mm/util.c | 32 - mm/vmacache.c | 117 - mm/vmstat.c | 4 - tools/include/linux/slab.h | 4 + tools/testing/radix-tree/.gitignore | 2 + tools/testing/radix-tree/Makefile | 9 +- tools/testing/radix-tree/generated/autoconf.h | 1 + tools/testing/radix-tree/linux.c | 160 +- tools/testing/radix-tree/linux/kernel.h | 1 + tools/testing/radix-tree/linux/lockdep.h | 2 + tools/testing/radix-tree/linux/maple_tree.h | 7 + tools/testing/radix-tree/maple.c | 59 + .../radix-tree/trace/events/maple_tree.h | 3 + 89 files changed, 47833 insertions(+), 1823 deletions(-) create mode 100644 Documentation/core-api/maple_tree.rst create mode 100644 include/linux/maple_tree.h delete mode 100644 include/linux/vmacache.h create mode 100644 include/trace/events/maple_tree.h create mode 100644 lib/maple_tree.c create mode 100644 lib/test_maple_tree.c delete mode 100644 mm/vmacache.c create mode 100644 tools/testing/radix-tree/linux/maple_tree.h create mode 100644 tools/testing/radix-tree/maple.c create mode 100644 tools/testing/radix-tree/trace/events/maple_tree.h -- 2.35.1
