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authorLinus Torvalds <torvalds@linux-foundation.org>2023-08-30 00:25:26 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2023-08-30 00:25:26 +0300
commitb96a3e9142fdf346b05b20e867b4f0dfca119e96 (patch)
treeb338a8f8930abc24888fc3871c6627f6ad46e23b /Documentation/admin-guide/mm/damon/usage.rst
parent651a00bc56403161351090a9d7ddbd7095975324 (diff)
parent52ae298e3e5c9be5bb95e1c6d9199e5210f2a156 (diff)
downloadlinux-b96a3e9142fdf346b05b20e867b4f0dfca119e96.tar.xz
Merge tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton: - Some swap cleanups from Ma Wupeng ("fix WARN_ON in add_to_avail_list") - Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which reduces the special-case code for handling hugetlb pages in GUP. It also speeds up GUP handling of transparent hugepages. - Peng Zhang provides some maple tree speedups ("Optimize the fast path of mas_store()"). - Sergey Senozhatsky has improved te performance of zsmalloc during compaction (zsmalloc: small compaction improvements"). - Domenico Cerasuolo has developed additional selftest code for zswap ("selftests: cgroup: add zswap test program"). - xu xin has doe some work on KSM's handling of zero pages. These changes are mainly to enable the user to better understand the effectiveness of KSM's treatment of zero pages ("ksm: support tracking KSM-placed zero-pages"). - Jeff Xu has fixes the behaviour of memfd's MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED"). - David Howells has fixed an fscache optimization ("mm, netfs, fscache: Stop read optimisation when folio removed from pagecache"). - Axel Rasmussen has given userfaultfd the ability to simulate memory poisoning ("add UFFDIO_POISON to simulate memory poisoning with UFFD"). - Miaohe Lin has contributed some routine maintenance work on the memory-failure code ("mm: memory-failure: remove unneeded PageHuge() check"). - Peng Zhang has contributed some maintenance work on the maple tree code ("Improve the validation for maple tree and some cleanup"). - Hugh Dickins has optimized the collapsing of shmem or file pages into THPs ("mm: free retracted page table by RCU"). - Jiaqi Yan has a patch series which permits us to use the healthy subpages within a hardware poisoned huge page for general purposes ("Improve hugetlbfs read on HWPOISON hugepages"). - Kemeng Shi has done some maintenance work on the pagetable-check code ("Remove unused parameters in page_table_check"). - More folioification work from Matthew Wilcox ("More filesystem folio conversions for 6.6"), ("Followup folio conversions for zswap"). And from ZhangPeng ("Convert several functions in page_io.c to use a folio"). - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext"). - Baoquan He has converted some architectures to use the GENERIC_IOREMAP ioremap()/iounmap() code ("mm: ioremap: Convert architectures to take GENERIC_IOREMAP way"). - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support batched/deferred tlb shootdown during page reclamation/migration"). - Better maple tree lockdep checking from Liam Howlett ("More strict maple tree lockdep"). Liam also developed some efficiency improvements ("Reduce preallocations for maple tree"). - Cleanup and optimization to the secondary IOMMU TLB invalidation, from Alistair Popple ("Invalidate secondary IOMMU TLB on permission upgrade"). - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes for arm64"). - Kemeng Shi provides some maintenance work on the compaction code ("Two minor cleanups for compaction"). - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle most file-backed faults under the VMA lock"). - Aneesh Kumar contributes code to use the vmemmap optimization for DAX on ppc64, under some circumstances ("Add support for DAX vmemmap optimization for ppc64"). - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client data in page_ext"), ("minor cleanups to page_ext header"). - Some zswap cleanups from Johannes Weiner ("mm: zswap: three cleanups"). - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan"). - VMA handling cleanups from Kefeng Wang ("mm: convert to vma_is_initial_heap/stack()"). - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes: implement DAMOS tried total bytes file"), ("Extend DAMOS filters for address ranges and DAMON monitoring targets"). - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction"). - Liam Howlett has improved the maple tree node replacement code ("maple_tree: Change replacement strategy"). - ZhangPeng has a general code cleanup - use the K() macro more widely ("cleanup with helper macro K()"). - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for memmap on memory feature on ppc64"). - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list in page_alloc"), ("Two minor cleanups for get pageblock migratetype"). - Vishal Moola introduces a memory descriptor for page table tracking, "struct ptdesc" ("Split ptdesc from struct page"). - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups for vm.memfd_noexec"). - MM include file rationalization from Hugh Dickins ("arch: include asm/cacheflush.h in asm/hugetlb.h"). - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text output"). - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use object_cache instead of kmemleak_initialized"). - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor and _folio_order"). - A VMA locking scalability improvement from Suren Baghdasaryan ("Per-VMA lock support for swap and userfaults"). - pagetable handling cleanups from Matthew Wilcox ("New page table range API"). - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop using page->private on tail pages for THP_SWAP + cleanups"). - Cleanups and speedups to the hugetlb fault handling from Matthew Wilcox ("Change calling convention for ->huge_fault"). - Matthew Wilcox has also done some maintenance work on the MM subsystem documentation ("Improve mm documentation"). * tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (489 commits) maple_tree: shrink struct maple_tree maple_tree: clean up mas_wr_append() secretmem: convert page_is_secretmem() to folio_is_secretmem() nios2: fix flush_dcache_page() for usage from irq context hugetlb: add documentation for vma_kernel_pagesize() mm: add orphaned kernel-doc to the rst files. mm: fix clean_record_shared_mapping_range kernel-doc mm: fix get_mctgt_type() kernel-doc mm: fix kernel-doc warning from tlb_flush_rmaps() mm: remove enum page_entry_size mm: allow ->huge_fault() to be called without the mmap_lock held mm: move PMD_ORDER to pgtable.h mm: remove checks for pte_index memcg: remove duplication detection for mem_cgroup_uncharge_swap mm/huge_memory: work on folio->swap instead of page->private when splitting folio mm/swap: inline folio_set_swap_entry() and folio_swap_entry() mm/swap: use dedicated entry for swap in folio mm/swap: stop using page->private on tail pages for THP_SWAP selftests/mm: fix WARNING comparing pointer to 0 selftests: cgroup: fix test_kmem_memcg_deletion kernel mem check ...
Diffstat (limited to 'Documentation/admin-guide/mm/damon/usage.rst')
-rw-r--r--Documentation/admin-guide/mm/damon/usage.rst76
1 files changed, 50 insertions, 26 deletions
diff --git a/Documentation/admin-guide/mm/damon/usage.rst b/Documentation/admin-guide/mm/damon/usage.rst
index 2d495fa85a0e..084f0a32b421 100644
--- a/Documentation/admin-guide/mm/damon/usage.rst
+++ b/Documentation/admin-guide/mm/damon/usage.rst
@@ -87,7 +87,7 @@ comma (","). ::
│ │ │ │ │ │ │ filters/nr_filters
│ │ │ │ │ │ │ │ 0/type,matching,memcg_id
│ │ │ │ │ │ │ stats/nr_tried,sz_tried,nr_applied,sz_applied,qt_exceeds
- │ │ │ │ │ │ │ tried_regions/
+ │ │ │ │ │ │ │ tried_regions/total_bytes
│ │ │ │ │ │ │ │ 0/start,end,nr_accesses,age
│ │ │ │ │ │ │ │ ...
│ │ │ │ │ │ ...
@@ -127,14 +127,18 @@ in the state. Writing ``commit`` to the ``state`` file makes kdamond reads the
user inputs in the sysfs files except ``state`` file again. Writing
``update_schemes_stats`` to ``state`` file updates the contents of stats files
for each DAMON-based operation scheme of the kdamond. For details of the
-stats, please refer to :ref:`stats section <sysfs_schemes_stats>`. Writing
-``update_schemes_tried_regions`` to ``state`` file updates the DAMON-based
-operation scheme action tried regions directory for each DAMON-based operation
-scheme of the kdamond. Writing ``clear_schemes_tried_regions`` to ``state``
-file clears the DAMON-based operating scheme action tried regions directory for
-each DAMON-based operation scheme of the kdamond. For details of the
-DAMON-based operation scheme action tried regions directory, please refer to
-:ref:`tried_regions section <sysfs_schemes_tried_regions>`.
+stats, please refer to :ref:`stats section <sysfs_schemes_stats>`.
+
+Writing ``update_schemes_tried_regions`` to ``state`` file updates the
+DAMON-based operation scheme action tried regions directory for each
+DAMON-based operation scheme of the kdamond. Writing
+``update_schemes_tried_bytes`` to ``state`` file updates only
+``.../tried_regions/total_bytes`` files. Writing
+``clear_schemes_tried_regions`` to ``state`` file clears the DAMON-based
+operating scheme action tried regions directory for each DAMON-based operation
+scheme of the kdamond. For details of the DAMON-based operation scheme action
+tried regions directory, please refer to :ref:`tried_regions section
+<sysfs_schemes_tried_regions>`.
If the state is ``on``, reading ``pid`` shows the pid of the kdamond thread.
@@ -359,15 +363,21 @@ number (``N``) to the file creates the number of child directories named ``0``
to ``N-1``. Each directory represents each filter. The filters are evaluated
in the numeric order.
-Each filter directory contains three files, namely ``type``, ``matcing``, and
-``memcg_path``. You can write one of two special keywords, ``anon`` for
-anonymous pages, or ``memcg`` for specific memory cgroup filtering. In case of
-the memory cgroup filtering, you can specify the memory cgroup of the interest
-by writing the path of the memory cgroup from the cgroups mount point to
-``memcg_path`` file. You can write ``Y`` or ``N`` to ``matching`` file to
-filter out pages that does or does not match to the type, respectively. Then,
-the scheme's action will not be applied to the pages that specified to be
-filtered out.
+Each filter directory contains six files, namely ``type``, ``matcing``,
+``memcg_path``, ``addr_start``, ``addr_end``, and ``target_idx``. To ``type``
+file, you can write one of four special keywords: ``anon`` for anonymous pages,
+``memcg`` for specific memory cgroup, ``addr`` for specific address range (an
+open-ended interval), or ``target`` for specific DAMON monitoring target
+filtering. In case of the memory cgroup filtering, you can specify the memory
+cgroup of the interest by writing the path of the memory cgroup from the
+cgroups mount point to ``memcg_path`` file. In case of the address range
+filtering, you can specify the start and end address of the range to
+``addr_start`` and ``addr_end`` files, respectively. For the DAMON monitoring
+target filtering, you can specify the index of the target between the list of
+the DAMON context's monitoring targets list to ``target_idx`` file. You can
+write ``Y`` or ``N`` to ``matching`` file to filter out pages that does or does
+not match to the type, respectively. Then, the scheme's action will not be
+applied to the pages that specified to be filtered out.
For example, below restricts a DAMOS action to be applied to only non-anonymous
pages of all memory cgroups except ``/having_care_already``.::
@@ -381,8 +391,14 @@ pages of all memory cgroups except ``/having_care_already``.::
echo /having_care_already > 1/memcg_path
echo N > 1/matching
-Note that filters are currently supported only when ``paddr``
-`implementation <sysfs_contexts>` is being used.
+Note that ``anon`` and ``memcg`` filters are currently supported only when
+``paddr`` `implementation <sysfs_contexts>` is being used.
+
+Also, memory regions that are filtered out by ``addr`` or ``target`` filters
+are not counted as the scheme has tried to those, while regions that filtered
+out by other type filters are counted as the scheme has tried to. The
+difference is applied to :ref:`stats <damos_stats>` and
+:ref:`tried regions <sysfs_schemes_tried_regions>`.
.. _sysfs_schemes_stats:
@@ -406,13 +422,21 @@ stats by writing a special keyword, ``update_schemes_stats`` to the relevant
schemes/<N>/tried_regions/
--------------------------
+This directory initially has one file, ``total_bytes``.
+
When a special keyword, ``update_schemes_tried_regions``, is written to the
-relevant ``kdamonds/<N>/state`` file, DAMON creates directories named integer
-starting from ``0`` under this directory. Each directory contains files
-exposing detailed information about each of the memory region that the
-corresponding scheme's ``action`` has tried to be applied under this directory,
-during next :ref:`aggregation interval <sysfs_monitoring_attrs>`. The
-information includes address range, ``nr_accesses``, and ``age`` of the region.
+relevant ``kdamonds/<N>/state`` file, DAMON updates the ``total_bytes`` file so
+that reading it returns the total size of the scheme tried regions, and creates
+directories named integer starting from ``0`` under this directory. Each
+directory contains files exposing detailed information about each of the memory
+region that the corresponding scheme's ``action`` has tried to be applied under
+this directory, during next :ref:`aggregation interval
+<sysfs_monitoring_attrs>`. The information includes address range,
+``nr_accesses``, and ``age`` of the region.
+
+Writing ``update_schemes_tried_bytes`` to the relevant ``kdamonds/<N>/state``
+file will only update the ``total_bytes`` file, and will not create the
+subdirectories.
The directories will be removed when another special keyword,
``clear_schemes_tried_regions``, is written to the relevant