pm24.git/Documentation/mm, branch cpufreq-rust

Merge tag 'mm-stable-2025-01-26-14-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-01-27T02:36:23Z

Pull MM updates from Andrew Morton: "The various patchsets are summarized below. Plus of course many indivudual patches which are described in their changelogs. - "Allocate and free frozen pages" from Matthew Wilcox reorganizes the page allocator so we end up with the ability to allocate and free zero-refcount pages. So that callers (ie, slab) can avoid a refcount inc & dec - "Support large folios for tmpfs" from Baolin Wang teaches tmpfs to use large folios other than PMD-sized ones - "Fix mm/rodata_test" from Petr Tesarik performs some maintenance and fixes for this small built-in kernel selftest - "mas_anode_descend() related cleanup" from Wei Yang tidies up part of the mapletree code - "mm: fix format issues and param types" from Keren Sun implements a few minor code cleanups - "simplify split calculation" from Wei Yang provides a few fixes and a test for the mapletree code - "mm/vma: make more mmap logic userland testable" from Lorenzo Stoakes continues the work of moving vma-related code into the (relatively) new mm/vma.c - "mm/page_alloc: gfp flags cleanups for alloc_contig_*()" from David Hildenbrand cleans up and rationalizes handling of gfp flags in the page allocator - "readahead: Reintroduce fix for improper RA window sizing" from Jan Kara is a second attempt at fixing a readahead window sizing issue. It should reduce the amount of unnecessary reading - "synchronously scan and reclaim empty user PTE pages" from Qi Zheng addresses an issue where "huge" amounts of pte pagetables are accumulated: https://lore.kernel.org/lkml/cover.1718267194.git.zhengqi.arch@bytedance.com/ Qi's series addresses this windup by synchronously freeing PTE memory within the context of madvise(MADV_DONTNEED) - "selftest/mm: Remove warnings found by adding compiler flags" from Muhammad Usama Anjum fixes some build warnings in the selftests code when optional compiler warnings are enabled - "mm: don't use __GFP_HARDWALL when migrating remote pages" from David Hildenbrand tightens the allocator's observance of __GFP_HARDWALL - "pkeys kselftests improvements" from Kevin Brodsky implements various fixes and cleanups in the MM selftests code, mainly pertaining to the pkeys tests - "mm/damon: add sample modules" from SeongJae Park enhances DAMON to estimate application working set size - "memcg/hugetlb: Rework memcg hugetlb charging" from Joshua Hahn provides some cleanups to memcg's hugetlb charging logic - "mm/swap_cgroup: remove global swap cgroup lock" from Kairui Song removes the global swap cgroup lock. A speedup of 10% for a tmpfs-based kernel build was demonstrated - "zram: split page type read/write handling" from Sergey Senozhatsky has several fixes and cleaups for zram in the area of zram_write_page(). A watchdog softlockup warning was eliminated - "move pagetable_*_dtor() to __tlb_remove_table()" from Kevin Brodsky cleans up the pagetable destructor implementations. A rare use-after-free race is fixed - "mm/debug: introduce and use VM_WARN_ON_VMG()" from Lorenzo Stoakes simplifies and cleans up the debugging code in the VMA merging logic - "Account page tables at all levels" from Kevin Brodsky cleans up and regularizes the pagetable ctor/dtor handling. This results in improvements in accounting accuracy - "mm/damon: replace most damon_callback usages in sysfs with new core functions" from SeongJae Park cleans up and generalizes DAMON's sysfs file interface logic - "mm/damon: enable page level properties based monitoring" from SeongJae Park increases the amount of information which is presented in response to DAMOS actions - "mm/damon: remove DAMON debugfs interface" from SeongJae Park removes DAMON's long-deprecated debugfs interfaces. Thus the migration to sysfs is completed - "mm/hugetlb: Refactor hugetlb allocation resv accounting" from Peter Xu cleans up and generalizes the hugetlb reservation accounting - "mm: alloc_pages_bulk: small API refactor" from Luiz Capitulino removes a never-used feature of the alloc_pages_bulk() interface - "mm/damon: extend DAMOS filters for inclusion" from SeongJae Park extends DAMOS filters to support not only exclusion (rejecting), but also inclusion (allowing) behavior - "Add zpdesc memory descriptor for zswap.zpool" from Alex Shi introduces a new memory descriptor for zswap.zpool that currently overlaps with struct page for now. This is part of the effort to reduce the size of struct page and to enable dynamic allocation of memory descriptors - "mm, swap: rework of swap allocator locks" from Kairui Song redoes and simplifies the swap allocator locking. A speedup of 400% was demonstrated for one workload. As was a 35% reduction for kernel build time with swap-on-zram - "mm: update mips to use do_mmap(), make mmap_region() internal" from Lorenzo Stoakes reworks MIPS's use of mmap_region() so that mmap_region() can be made MM-internal - "mm/mglru: performance optimizations" from Yu Zhao fixes a few MGLRU regressions and otherwise improves MGLRU performance - "Docs/mm/damon: add tuning guide and misc updates" from SeongJae Park updates DAMON documentation - "Cleanup for memfd_create()" from Isaac Manjarres does that thing - "mm: hugetlb+THP folio and migration cleanups" from David Hildenbrand provides various cleanups in the areas of hugetlb folios, THP folios and migration - "Uncached buffered IO" from Jens Axboe implements the new RWF_DONTCACHE flag which provides synchronous dropbehind for pagecache reading and writing. To permite userspace to address issues with massive buildup of useless pagecache when reading/writing fast devices - "selftests/mm: virtual_address_range: Reduce memory" from Thomas Weißschuh fixes and optimizes some of the MM selftests" * tag 'mm-stable-2025-01-26-14-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) mm/compaction: fix UBSAN shift-out-of-bounds warning s390/mm: add missing ctor/dtor on page table upgrade kasan: sw_tags: use str_on_off() helper in kasan_init_sw_tags() tools: add VM_WARN_ON_VMG definition mm/damon/core: use str_high_low() helper in damos_wmark_wait_us() seqlock: add missing parameter documentation for raw_seqcount_try_begin() mm/page-writeback: consolidate wb_thresh bumping logic into __wb_calc_thresh mm/page_alloc: remove the incorrect and misleading comment zram: remove zcomp_stream_put() from write_incompressible_page() mm: separate move/undo parts from migrate_pages_batch() mm/kfence: use str_write_read() helper in get_access_type() selftests/mm/mkdirty: fix memory leak in test_uffdio_copy() kasan: hw_tags: Use str_on_off() helper in kasan_init_hw_tags() selftests/mm: virtual_address_range: avoid reading from VM_IO mappings selftests/mm: vm_util: split up /proc/self/smaps parsing selftests/mm: virtual_address_range: unmap chunks after validation selftests/mm: virtual_address_range: mmap() without PROT_WRITE selftests/memfd/memfd_test: fix possible NULL pointer dereference mm: add FGP_DONTCACHE folio creation flag mm: call filemap_fdatawrite_range_kick() after IOCB_DONTCACHE issue ...

Docs/mm/damon: add an example monitoring intervals tuning

2025-01-26T04:22:39Z

Add a DAMON monitoring intervals tuning example that contains output from a demonstration of the guide on a real server workload system. The example with real world numbers will help users better understanding the guide instructions and what outputs they can expect and verify. Those will again help finding the rooms for improvements on the guide. Link: https://lkml.kernel.org/r/20250110185232.54907-3-sj@kernel.org Signed-off-by: SeongJae Park Cc: Honggyu Kim Cc: Jonathan Corbet Cc: Yunjeong Mun Signed-off-by: Andrew Morton

Docs/mm/damon/design: add monitoring parameters tuning guide

2025-01-26T04:22:39Z

Patch series "Docs/mm/damon: add tuning guide and misc updates". Add DAMON monitoring parameters tuning guide (patches 1 and 2), with misc documentation fixes (patch 3), updates (patch 4) and clarifications (patch 5). This patch (of 5): DAMON monitoring parameters including sampling and aggregation intervals should be tuned for given workloads. However, the fact is not explicitly documented. Also there is no official guide to help the tuning. This apparently confused a number of people[1] at best, or made people forgive DAMON without tuning. Add a guide on the design document. [1] https://lore.kernel.org/20241202175459.2005526-1-sj@kernel.org Link: https://lkml.kernel.org/r/20250110185232.54907-1-sj@kernel.org Link: https://lkml.kernel.org/r/20250110185232.54907-2-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Cc: Honggyu Kim Cc: Yunjeong Mun Signed-off-by: Andrew Morton

Docs/mm/damon/design: document allow/reject DAMOS filter behaviors

2025-01-26T04:22:32Z

Update DAMOS filters design document to describe the allow/reject behavior of filters. Link: https://lkml.kernel.org/r/20250109175126.57878-8-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Signed-off-by: Andrew Morton

Docs/mm/damon/design: update for removal of DAMON debugfs interface

2025-01-26T04:22:29Z

It's time to remove DAMON debugfs interface, which has deprecated long before in February 2023. Read the cover letter of this patch series for more details. Update DAMON design documentation to stop mentioning about the interface, to avoid unnecessary confuses. Link: https://lkml.kernel.org/r/20250106191941.107070-4-sj@kernel.org Signed-off-by: SeongJae Park Cc: Alex Shi Cc: Brendan Higgins Cc: David Gow Cc: Hu Haowen <2023002089@link.tyut.edu.cn> Cc: Jonathan Corbet Cc: Rae Moar Cc: Shuah Khan Cc: Yanteng Si Signed-off-by: Andrew Morton

Docs/mm/damon/design: document per-region sz_filter_passed stat

2025-01-26T04:22:28Z

Update 'Regions Walking' section of design document for the newly added per-region operations set handling DAMOS filters-passed bytes. Link: https://lkml.kernel.org/r/20250106193401.109161-15-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Signed-off-by: Andrew Morton

Docs/mm/damon/design: document sz_ops_filter_passed

2025-01-26T04:22:27Z

Document the new per-scheme accumulated stat for total bytes that passed the operations set layer-handled DAMOS filters on the design document. Link: https://lkml.kernel.org/r/20250106193401.109161-10-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Signed-off-by: Andrew Morton

Docs/admin-guide/mm/damon/usage: link damos stat design doc

2025-01-26T04:22:26Z

DAMON sysfs usage document focuses on usage, rather than the detail of the stat metric itself. Add a link to the design document on DAMOS stat usage section. Link: https://lkml.kernel.org/r/20250106193401.109161-4-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Signed-off-by: Andrew Morton

Docs/mm/damon/design: add 'statistics' section

2025-01-26T04:22:26Z

DAMOS stats are important feature for tuning of DAMOS-based access-aware system operation, and efficient access pattern monitoring. But not well documented on the design document. Add a section on the document. Link: https://lkml.kernel.org/r/20250106193401.109161-3-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Signed-off-by: Andrew Morton

Docs/mm/damon/design: document DAMOS regions walking

2025-01-26T04:22:26Z

DAMOS' regions walking is a feature for efficiently retrieving monitoring results or DAMOS-internal behavior. It can be useful for multiple purposes including investigations and tuning. Add a section for it on the design document. Link: https://lkml.kernel.org/r/20250103174400.54890-9-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Signed-off-by: Andrew Morton