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2023-08-18Documentation: Fix typosBjorn Helgaas1-2/+2
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-07-14Documentation: admin-guide: correct "it's" to possessive "its"Randy Dunlap1-1/+1
Correct 2 uses of "it's" to the possessive "its" as needed. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Darrick J. Wong <djwong@kernel.org> Cc: linux-xfs@vger.kernel.org Cc: linux-mm@kvack.org Cc: Jonathan Corbet <corbet@lwn.net> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230703232024.8069-1-rdunlap@infradead.org
2023-06-20Docs/admin-guide/mm/damon/usage: update the ways for getting monitoring resultsSeongJae Park1-8/+12
The recommended ways for getting DAMON monitoring results are using tried_regions sysfs directory for partial snapshot of the results, and DAMON tracepoint for full record of the results. However, the tried_regions sysfs directory usage has not sufficiently updated on some sections of the DAMON usage document. Update those. Link: https://lkml.kernel.org/r/20230616191742.87531-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-20Docs/admin-guide/mm/damon/usage: clarify quotas and watermarks sysfs interfaceSeongJae Park1-2/+9
Explanation of DAMOS quotas and watermarks are not clearly explaining the meaning and expectation of each file. Add more clarification for those. Link: https://lkml.kernel.org/r/20230616191742.87531-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-20Docs/admin-guide/mm/damon/usage: link design document for DAMOSSeongJae Park1-67/+37
The background and concept of DAMOS is redundantly documented, in the design document and the usage document. Replace the duplicated ones in usage document with links to the design document. Link: https://lkml.kernel.org/r/20230616191742.87531-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-20Docs/admin-guide/mm/damon/usage: remove unnecessary sentences about ↵SeongJae Park1-7/+5
supported address spaces Brief explanation of DAMON user space tool and sysfs interface are unnecessarily and repeatedly mentioning the list of address spaces that DAMON is supporting. Remove those. Link: https://lkml.kernel.org/r/20230616191742.87531-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-20Docs/admin-guide/mm/damon/usage: fix typos in references and commasSeongJae Park1-4/+3
Fix typos including a unnecessary comma and incomplete ':ref:' keywords. Link: https://lkml.kernel.org/r/20230616191742.87531-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-20Docs/admin-guide/mm/damon/start: update DAMOS example commandSeongJae Park1-5/+5
DAMON user-space tool, damo, has deprecated[1] its old DAMOS schemes specification format. However, an example of DAMON documentation is still using it. Update the example to use one of the alternative options. [1] https://github.com/awslabs/damo/commit/e9950ae68f6c Link: https://lkml.kernel.org/r/20230616191742.87531-3-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-05-05Merge tag 'docs-6.4-2' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull more documentation updates from Jonathan Corbet: "A handful of late-arriving documentation fixes, plus one Spanish translation that has been ready for some time but got applied late" * tag 'docs-6.4-2' of git://git.lwn.net/linux: docs/sp_SP: Add translation of process/adding-syscalls CREDITS: Update email address for Mat Martineau Documentation: update kernel stack for x86_64 docs: Remove unnecessary unicode character docs: fix "Reviewd" typo Documentation: timers: hrtimers: Make hybrid union historical docs/admin-guide/mm/ksm.rst fix intraface -> interface typo doc:it_IT: fix some typos
2023-04-28Merge tag 'mm-stable-2023-04-27-15-30' of ↵Linus Torvalds2-1/+29
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of switching from a user process to a kernel thread. - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj Raghav. - zsmalloc performance improvements from Sergey Senozhatsky. - Yue Zhao has found and fixed some data race issues around the alteration of memcg userspace tunables. - VFS rationalizations from Christoph Hellwig: - removal of most of the callers of write_one_page() - make __filemap_get_folio()'s return value more useful - Luis Chamberlain has changed tmpfs so it no longer requires swap backing. Use `mount -o noswap'. - Qi Zheng has made the slab shrinkers operate locklessly, providing some scalability benefits. - Keith Busch has improved dmapool's performance, making part of its operations O(1) rather than O(n). - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd, permitting userspace to wr-protect anon memory unpopulated ptes. - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive rather than exclusive, and has fixed a bunch of errors which were caused by its unintuitive meaning. - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature, which causes minor faults to install a write-protected pte. - Vlastimil Babka has done some maintenance work on vma_merge(): cleanups to the kernel code and improvements to our userspace test harness. - Cleanups to do_fault_around() by Lorenzo Stoakes. - Mike Rapoport has moved a lot of initialization code out of various mm/ files and into mm/mm_init.c. - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for DRM, but DRM doesn't use it any more. - Lorenzo has also coverted read_kcore() and vread() to use iterators and has thereby removed the use of bounce buffers in some cases. - Lorenzo has also contributed further cleanups of vma_merge(). - Chaitanya Prakash provides some fixes to the mmap selftesting code. - Matthew Wilcox changes xfs and afs so they no longer take sleeping locks in ->map_page(), a step towards RCUification of pagefaults. - Suren Baghdasaryan has improved mmap_lock scalability by switching to per-VMA locking. - Frederic Weisbecker has reworked the percpu cache draining so that it no longer causes latency glitches on cpu isolated workloads. - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig logic. - Liu Shixin has changed zswap's initialization so we no longer waste a chunk of memory if zswap is not being used. - Yosry Ahmed has improved the performance of memcg statistics flushing. - David Stevens has fixed several issues involving khugepaged, userfaultfd and shmem. - Christoph Hellwig has provided some cleanup work to zram's IO-related code paths. - David Hildenbrand has fixed up some issues in the selftest code's testing of our pte state changing. - Pankaj Raghav has made page_endio() unneeded and has removed it. - Peter Xu contributed some rationalizations of the userfaultfd selftests. - Yosry Ahmed has fixed an issue around memcg's page recalim accounting. - Chaitanya Prakash has fixed some arm-related issues in the selftests/mm code. - Longlong Xia has improved the way in which KSM handles hwpoisoned pages. - Peter Xu fixes a few issues with uffd-wp at fork() time. - Stefan Roesch has changed KSM so that it may now be used on a per-process and per-cgroup basis. * tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm,unmap: avoid flushing TLB in batch if PTE is inaccessible shmem: restrict noswap option to initial user namespace mm/khugepaged: fix conflicting mods to collapse_file() sparse: remove unnecessary 0 values from rc mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area() hugetlb: pte_alloc_huge() to replace huge pte_alloc_map() maple_tree: fix allocation in mas_sparse_area() mm: do not increment pgfault stats when page fault handler retries zsmalloc: allow only one active pool compaction context selftests/mm: add new selftests for KSM mm: add new KSM process and sysfs knobs mm: add new api to enable ksm per process mm: shrinkers: fix debugfs file permissions mm: don't check VMA write permissions if the PTE/PMD indicates write permissions migrate_pages_batch: fix statistics for longterm pin retry userfaultfd: use helper function range_in_vma() lib/show_mem.c: use for_each_populated_zone() simplify code mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list() fs/buffer: convert create_page_buffers to folio_create_buffers fs/buffer: add folio_create_empty_buffers helper ...
2023-04-26docs/admin-guide/mm/ksm.rst fix intraface -> interface typoDonald Hunter1-1/+1
Fix typo from 'intraface' to 'interface' in admin guide for KSM. Signed-off-by: Donald Hunter <donald.hunter@gmail.com> Link: https://lore.kernel.org/r/20230424080305.2985-1-donald.hunter@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-04-22mm: add new KSM process and sysfs knobsStefan Roesch1-1/+4
This adds the general_profit KSM sysfs knob and the process profit metric knobs to ksm_stat. 1) expose general_profit metric The documentation mentions a general profit metric, however this metric is not calculated. In addition the formula depends on the size of internal structures, which makes it more difficult for an administrator to make the calculation. Adding the metric for a better user experience. 2) document general_profit sysfs knob 3) calculate ksm process profit metric The ksm documentation mentions the process profit metric and how to calculate it. This adds the calculation of the metric. 4) mm: expose ksm process profit metric in ksm_stat This exposes the ksm process profit metric in /proc/<pid>/ksm_stat. The documentation mentions the formula for the ksm process profit metric, however it does not calculate it. In addition the formula depends on the size of internal structures. So it makes sense to expose it. 5) document new procfs ksm knobs Link: https://lkml.kernel.org/r/20230418051342.1919757-3-shr@devkernel.io Signed-off-by: Stefan Roesch <shr@devkernel.io> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-06mm: userfaultfd: add UFFDIO_CONTINUE_MODE_WP to install WP PTEsAxel Rasmussen1-0/+8
UFFDIO_COPY already has UFFDIO_COPY_MODE_WP, so when installing a new PTE to resolve a missing fault, one can install a write-protected one. This is useful when using UFFDIO_REGISTER_MODE_{MISSING,WP} in combination. This was motivated by testing HugeTLB HGM [1], and in particular its interaction with userfaultfd features. Existing userfaultfd code supports using WP and MINOR modes together (i.e. you can register an area with both enabled), but without this CONTINUE flag the combination is in practice unusable. So, add an analogous UFFDIO_CONTINUE_MODE_WP, which does the same thing as UFFDIO_COPY_MODE_WP, but for *minor* faults. Update the selftest to do some very basic exercising of the new flag. Update Documentation/ to describe how these flags are used (neither the COPY nor the new CONTINUE versions of this mode flag were described there before). [1]: https://patchwork.kernel.org/project/linux-mm/cover/20230218002819.1486479-1-jthoughton@google.com/ Link: https://lkml.kernel.org/r/20230314221250.682452-5-axelrasmussen@google.com Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Acked-by: Peter Xu <peterx@redhat.com> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nadav Amit <namit@vmware.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-06mm/uffd: UFFD_FEATURE_WP_UNPOPULATEDPeter Xu1-0/+17
Patch series "mm/uffd: Add feature bit UFFD_FEATURE_WP_UNPOPULATED", v4. The new feature bit makes anonymous memory acts the same as file memory on userfaultfd-wp in that it'll also wr-protect none ptes. It can be useful in two cases: (1) Uffd-wp app that needs to wr-protect none ptes like QEMU snapshot, so pre-fault can be replaced by enabling this flag and speed up protections (2) It helps to implement async uffd-wp mode that Muhammad is working on [1] It's debatable whether this is the most ideal solution because with the new feature bit set, wr-protect none pte needs to pre-populate the pgtables to the last level (PAGE_SIZE). But it seems fine so far to service either purpose above, so we can leave optimizations for later. The series brings pte markers to anonymous memory too. There's some change in the common mm code path in the 1st patch, great to have some eye looking at it, but hopefully they're still relatively straightforward. This patch (of 2): This is a new feature that controls how uffd-wp handles none ptes. When it's set, the kernel will handle anonymous memory the same way as file memory, by allowing the user to wr-protect unpopulated ptes. File memories handles none ptes consistently by allowing wr-protecting of none ptes because of the unawareness of page cache being exist or not. For anonymous it was not as persistent because we used to assume that we don't need protections on none ptes or known zero pages. One use case of such a feature bit was VM live snapshot, where if without wr-protecting empty ptes the snapshot can contain random rubbish in the holes of the anonymous memory, which can cause misbehave of the guest when the guest OS assumes the pages should be all zeros. QEMU worked it around by pre-populate the section with reads to fill in zero page entries before starting the whole snapshot process [1]. Recently there's another need raised on using userfaultfd wr-protect for detecting dirty pages (to replace soft-dirty in some cases) [2]. In that case if without being able to wr-protect none ptes by default, the dirty info can get lost, since we cannot treat every none pte to be dirty (the current design is identify a page dirty based on uffd-wp bit being cleared). In general, we want to be able to wr-protect empty ptes too even for anonymous. This patch implements UFFD_FEATURE_WP_UNPOPULATED so that it'll make uffd-wp handling on none ptes being consistent no matter what the memory type is underneath. It doesn't have any impact on file memories so far because we already have pte markers taking care of that. So it only affects anonymous. The feature bit is by default off, so the old behavior will be maintained. Sometimes it may be wanted because the wr-protect of none ptes will contain overheads not only during UFFDIO_WRITEPROTECT (by applying pte markers to anonymous), but also on creating the pgtables to store the pte markers. So there's potentially less chance of using thp on the first fault for a none pmd or larger than a pmd. The major implementation part is teaching the whole kernel to understand pte markers even for anonymously mapped ranges, meanwhile allowing the UFFDIO_WRITEPROTECT ioctl to apply pte markers for anonymous too when the new feature bit is set. Note that even if the patch subject starts with mm/uffd, there're a few small refactors to major mm path of handling anonymous page faults. But they should be straightforward. With WP_UNPOPUATED, application like QEMU can avoid pre-read faults all the memory before wr-protect during taking a live snapshot. Quotting from Muhammad's test result here [3] based on a simple program [4]: (1) With huge page disabled echo madvise > /sys/kernel/mm/transparent_hugepage/enabled ./uffd_wp_perf Test DEFAULT: 4 Test PRE-READ: 1111453 (pre-fault 1101011) Test MADVISE: 278276 (pre-fault 266378) Test WP-UNPOPULATE: 11712 (2) With Huge page enabled echo always > /sys/kernel/mm/transparent_hugepage/enabled ./uffd_wp_perf Test DEFAULT: 4 Test PRE-READ: 22521 (pre-fault 22348) Test MADVISE: 4909 (pre-fault 4743) Test WP-UNPOPULATE: 14448 There'll be a great perf boost for no-thp case, while for thp enabled with extreme case of all-thp-zero WP_UNPOPULATED can be slower than MADVISE, but that's low possibility in reality, also the overhead was not reduced but postponed until a follow up write on any huge zero thp, so potentially it is faster by making the follow up writes slower. [1] https://lore.kernel.org/all/20210401092226.102804-4-andrey.gruzdev@virtuozzo.com/ [2] https://lore.kernel.org/all/Y+v2HJ8+3i%2FKzDBu@x1n/ [3] https://lore.kernel.org/all/d0eb0a13-16dc-1ac1-653a-78b7273781e3@collabora.com/ [4] https://github.com/xzpeter/clibs/blob/master/uffd-test/uffd-wp-perf.c [peterx@redhat.com: comment changes, oneliner fix to khugepaged] Link: https://lkml.kernel.org/r/ZB2/8jPhD3fpx5U8@x1n Link: https://lkml.kernel.org/r/20230309223711.823547-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20230309223711.823547-2-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Muhammad Usama Anjum <usama.anjum@collabora.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Paul Gofman <pgofman@codeweavers.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-29mm, pagemap: remove SLOB and SLQB from comments and documentationVlastimil Babka1-3/+3
SLOB has been removed and SLQB never merged, so remove their mentions from comments and documentation of pagemap. In stable_page_flags() also correct an outdated comment mentioning that PageBuddy() means a page->_refcount of -1, and remove compound_head() from the PageSlab() call, as that's already implicitly there thanks to PF_NO_TAIL. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
2023-02-24Merge tag 'mm-stable-2023-02-20-13-37' of ↵Linus Torvalds6-30/+104
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Daniel Verkamp has contributed a memfd series ("mm/memfd: add F_SEAL_EXEC") which permits the setting of the memfd execute bit at memfd creation time, with the option of sealing the state of the X bit. - Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset() thread-safe for pmd unshare") which addresses a rare race condition related to PMD unsharing. - Several folioification patch serieses from Matthew Wilcox, Vishal Moola, Sidhartha Kumar and Lorenzo Stoakes - Johannes Weiner has a series ("mm: push down lock_page_memcg()") which does perform some memcg maintenance and cleanup work. - SeongJae Park has added DAMOS filtering to DAMON, with the series "mm/damon/core: implement damos filter". These filters provide users with finer-grained control over DAMOS's actions. SeongJae has also done some DAMON cleanup work. - Kairui Song adds a series ("Clean up and fixes for swap"). - Vernon Yang contributed the series "Clean up and refinement for maple tree". - Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It adds to MGLRU an LRU of memcgs, to improve the scalability of global reclaim. - David Hildenbrand has added some userfaultfd cleanup work in the series "mm: uffd-wp + change_protection() cleanups". - Christoph Hellwig has removed the generic_writepages() library function in the series "remove generic_writepages". - Baolin Wang has performed some maintenance on the compaction code in his series "Some small improvements for compaction". - Sidhartha Kumar is doing some maintenance work on struct page in his series "Get rid of tail page fields". - David Hildenbrand contributed some cleanup, bugfixing and generalization of pte management and of pte debugging in his series "mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with swap PTEs". - Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation flag in the series "Discard __GFP_ATOMIC". - Sergey Senozhatsky has improved zsmalloc's memory utilization with his series "zsmalloc: make zspage chain size configurable". - Joey Gouly has added prctl() support for prohibiting the creation of writeable+executable mappings. The previous BPF-based approach had shortcomings. See "mm: In-kernel support for memory-deny-write-execute (MDWE)". - Waiman Long did some kmemleak cleanup and bugfixing in the series "mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF". - T.J. Alumbaugh has contributed some MGLRU cleanup work in his series "mm: multi-gen LRU: improve". - Jiaqi Yan has provided some enhancements to our memory error statistics reporting, mainly by presenting the statistics on a per-node basis. See the series "Introduce per NUMA node memory error statistics". - Mel Gorman has a second and hopefully final shot at fixing a CPU-hog regression in compaction via his series "Fix excessive CPU usage during compaction". - Christoph Hellwig does some vmalloc maintenance work in the series "cleanup vfree and vunmap". - Christoph Hellwig has removed block_device_operations.rw_page() in ths series "remove ->rw_page". - We get some maple_tree improvements and cleanups in Liam Howlett's series "VMA tree type safety and remove __vma_adjust()". - Suren Baghdasaryan has done some work on the maintainability of our vm_flags handling in the series "introduce vm_flags modifier functions". - Some pagemap cleanup and generalization work in Mike Rapoport's series "mm, arch: add generic implementation of pfn_valid() for FLATMEM" and "fixups for generic implementation of pfn_valid()" - Baoquan He has done some work to make /proc/vmallocinfo and /proc/kcore better represent the real state of things in his series "mm/vmalloc.c: allow vread() to read out vm_map_ram areas". - Jason Gunthorpe rationalized the GUP system's interface to the rest of the kernel in the series "Simplify the external interface for GUP". - SeongJae Park wishes to migrate people from DAMON's debugfs interface over to its sysfs interface. To support this, we'll temporarily be printing warnings when people use the debugfs interface. See the series "mm/damon: deprecate DAMON debugfs interface". - Andrey Konovalov provided the accurately named "lib/stackdepot: fixes and clean-ups" series. - Huang Ying has provided a dramatic reduction in migration's TLB flush IPI rates with the series "migrate_pages(): batch TLB flushing". - Arnd Bergmann has some objtool fixups in "objtool warning fixes". * tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (505 commits) include/linux/migrate.h: remove unneeded externs mm/memory_hotplug: cleanup return value handing in do_migrate_range() mm/uffd: fix comment in handling pte markers mm: change to return bool for isolate_movable_page() mm: hugetlb: change to return bool for isolate_hugetlb() mm: change to return bool for isolate_lru_page() mm: change to return bool for folio_isolate_lru() objtool: add UACCESS exceptions for __tsan_volatile_read/write kmsan: disable ftrace in kmsan core code kasan: mark addr_has_metadata __always_inline mm: memcontrol: rename memcg_kmem_enabled() sh: initialize max_mapnr m68k/nommu: add missing definition of ARCH_PFN_OFFSET mm: percpu: fix incorrect size in pcpu_obj_full_size() maple_tree: reduce stack usage with gcc-9 and earlier mm: page_alloc: call panic() when memoryless node allocation fails mm: multi-gen LRU: avoid futile retries migrate_pages: move THP/hugetlb migration support check to simplify code migrate_pages: batch flushing TLB migrate_pages: share more code between _unmap and _move ...
2023-02-22Merge tag 'docs-6.3' of git://git.lwn.net/linuxLinus Torvalds17-52/+20
Pull documentation updates from Jonathan Corbet: "It has been a moderately calm cycle for documentation; the significant changes include: - Some significant additions to the memory-management documentation - Some improvements to navigation in the HTML-rendered docs - More Spanish and Chinese translations ... and the usual set of typo fixes and such" * tag 'docs-6.3' of git://git.lwn.net/linux: (68 commits) Documentation/watchdog/hpwdt: Fix Format Documentation/watchdog/hpwdt: Fix Reference Documentation: core-api: padata: correct spelling docs/mm: Physical Memory: correct spelling in reference to CONFIG_PAGE_EXTENSION docs: Use HTML comments for the kernel-toc SPDX line docs: Add more information to the HTML sidebar Documentation: KVM: Update AMD memory encryption link printk: Document that CONFIG_BOOT_PRINTK_DELAY required for boot_delay= Documentation: userspace-api: correct spelling Documentation: sparc: correct spelling Documentation: driver-api: correct spelling Documentation: admin-guide: correct spelling docs: add workload-tracing document to admin-guide docs/admin-guide/mm: remove useless markup docs/mm: remove useless markup docs/mm: Physical Memory: remove useless markup docs/sp_SP: Add process magic-number translation docs: ftrace: always use canonical ftrace path Doc/damon: fix the data path error dma-buf: Add "dma-buf" to title of documentation ...
2023-02-14Docs/admin-guide/mm/damon/usage: add DAMON debugfs interface deprecation noticeSeongJae Park1-7/+13
Patch series "mm/damon: deprecate DAMON debugfs interface". DAMON debugfs interface has announced to be deprecated after >v5.15 LTS kernel is released. And v6.1.y has been announced to be an LTS[1]. Though the announcement was there for a while, some people might not have noticed that so far. Also, some users could depend on it and have problems at movng to the alternative (DAMON sysfs interface). For such cases, keep the code and documents with warning messages and contacts to ask helps for the deprecation. [1] https://git.kernel.org/pub/scm/docs/kernel/website.git/commit/?id=332e9121320bc7461b2d3a79665caf153e51732c This patch (of 3): DAMON debugfs interface has announced to be deprecated after >v5.15 LTS kernel is released. And, v6.1.y has announced to be an LTS[1]. Though the announcement was there for a while, some people might not noticed that so far. Also, some users could depend on it and have problems at movng to the alternative (DAMON sysfs interface). For such cases, note DAMON debugfs interface as deprecated, and contacts to ask helps on the document. [1] https://git.kernel.org/pub/scm/docs/kernel/website.git/commit/?id=332e9121320bc7461b2d3a79665caf153e51732c Link: https://lkml.kernel.org/r/20230209192009.7885-1-sj@kernel.org Link: https://lkml.kernel.org/r/20230209192009.7885-2-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-03Docs/admin-guide/mm/damon/usage: update DAMOS actions/filters supports of ↵SeongJae Park1-13/+28
each DAMON operations set Supports of each DAMOS action and filters are up to DAMON operations set implementation, but it's not mentioned in detail on the documentation. Update the information on the usage document. Link: https://lkml.kernel.org/r/20230110190400.119388-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02Documentation: admin-guide: correct spellingRandy Dunlap2-3/+3
Correct spelling problems for Documentation/admin-guide/ as reported by codespell. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan.x@bytedance.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: cgroups@vger.kernel.org Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@kernel.org> Cc: dm-devel@redhat.com Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: linux-media@vger.kernel.org Cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230129231053.20863-2-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-02-02docs/admin-guide/mm: remove useless markupMike Rapoport (IBM)15-45/+13
It is enough to use a file name to cross-reference another rst document. Jon says: The right things will happen in the HTML output, readers of the plain-text will know immediately where to go, and we don't have to add the label clutter. Drop reference markup and unnecessary labels and use plain file names. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Link: https://lore.kernel.org/r/20230201094156.991542-4-rppt@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-31Doc/damon: fix the data path errorHui Su2-4/+4
%s/modules/module/ Signed-off-by: Hui Su <suhui_kernel@163.com> Reviewed-by: Alex Shi <alexsshi@kernel.org> Reviewed-by: SeongJae Park <sj@kernel.org> Link: https://lore.kernel.org/r/Y9Tm1FiKBPKA2Tcx@localhost.localdomain Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-19Docs/admin-guide/mm/numaperf: increase depth of subsectionsSeongJae Park1-4/+4
Each section of numaperf.rst has zero depth, and therefore be exposed to the index of admin-guide/mm. Especially 'See Also' section on the index makes the document weird. Hide the sections from the index by giving the document a title and increasing the depth of each section. [sj@kernel.org: change title to fix duplicate label warning] Link: https://lkml.kernel.org/r/20230106194927.152663-1-sj@kernel.org Link: https://lkml.kernel.org/r/20230103180754.129637-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-19selftests/vm: rename selftests/vm to selftests/mmSeongJae Park1-3/+3
Rename selftets/vm to selftests/mm for being more consistent with the code, documentation, and tools directories, and won't be confused with virtual machines. [sj@kernel.org: convert missing vm->mm changes] Link: https://lkml.kernel.org/r/20230107230643.252273-1-sj@kernel.org Link: https://lkml.kernel.org/r/20230103180754.129637-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-19tools/vm: rename tools/vm to tools/mmSeongJae Park2-3/+3
Rename tools/vm to tools/mm for being more consistent with the code and documentation directories, and won't be confused with virtual machines. Link: https://lkml.kernel.org/r/20230103180754.129637-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-19Docs/admin-guide/mm/damon/usage: document DAMOS filters of sysfsSeongJae Park1-2/+46
Document about the newly added files for DAMOS filters on the DAMON usage document. Link: https://lkml.kernel.org/r/20221205230830.144349-11-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-19Docs/admin-guide/damon/reclaim: document 'skip_anon' parameterSeongJae Park1-0/+9
Document the newly added 'skip_anon' parameter of DAMON_RECLAIM, which can be used to avoid anonymous pages reclamation. Link: https://lkml.kernel.org/r/20221205230830.144349-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-12Docs/admin-guide/mm/zswap: remove zsmalloc's lack of writeback warningNhat Pham1-3/+1
Writeback has been implemented for zsmalloc, so this warning no longer holds. Link: https://lkml.kernel.org/r/20230106220016.172303-1-nphamcs@gmail.com Fixes: 9997bc017549a ("zsmalloc: implement writeback mechanism for zsmalloc") Suggested-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-12-14Merge tag 'mm-stable-2022-12-13' of ↵Linus Torvalds1-8/+51
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - More userfaultfs work from Peter Xu - Several convert-to-folios series from Sidhartha Kumar and Huang Ying - Some filemap cleanups from Vishal Moola - David Hildenbrand added the ability to selftest anon memory COW handling - Some cpuset simplifications from Liu Shixin - Addition of vmalloc tracing support by Uladzislau Rezki - Some pagecache folioifications and simplifications from Matthew Wilcox - A pagemap cleanup from Kefeng Wang: we have VM_ACCESS_FLAGS, so use it - Miguel Ojeda contributed some cleanups for our use of the __no_sanitize_thread__ gcc keyword. This series should have been in the non-MM tree, my bad - Naoya Horiguchi improved the interaction between memory poisoning and memory section removal for huge pages - DAMON cleanups and tuneups from SeongJae Park - Tony Luck fixed the handling of COW faults against poisoned pages - Peter Xu utilized the PTE marker code for handling swapin errors - Hugh Dickins reworked compound page mapcount handling, simplifying it and making it more efficient - Removal of the autonuma savedwrite infrastructure from Nadav Amit and David Hildenbrand - zram support for multiple compression streams from Sergey Senozhatsky - David Hildenbrand reworked the GUP code's R/O long-term pinning so that drivers no longer need to use the FOLL_FORCE workaround which didn't work very well anyway - Mel Gorman altered the page allocator so that local IRQs can remnain enabled during per-cpu page allocations - Vishal Moola removed the try_to_release_page() wrapper - Stefan Roesch added some per-BDI sysfs tunables which are used to prevent network block devices from dirtying excessive amounts of pagecache - David Hildenbrand did some cleanup and repair work on KSM COW breaking - Nhat Pham and Johannes Weiner have implemented writeback in zswap's zsmalloc backend - Brian Foster has fixed a longstanding corner-case oddity in file[map]_write_and_wait_range() - sparse-vmemmap changes for MIPS, LoongArch and NIOS2 from Feiyang Chen - Shiyang Ruan has done some work on fsdax, to make its reflink mode work better under xfstests. Better, but still not perfect - Christoph Hellwig has removed the .writepage() method from several filesystems. They only need .writepages() - Yosry Ahmed wrote a series which fixes the memcg reclaim target beancounting - David Hildenbrand has fixed some of our MM selftests for 32-bit machines - Many singleton patches, as usual * tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (313 commits) mm/hugetlb: set head flag before setting compound_order in __prep_compound_gigantic_folio mm: mmu_gather: allow more than one batch of delayed rmaps mm: fix typo in struct pglist_data code comment kmsan: fix memcpy tests mm: add cond_resched() in swapin_walk_pmd_entry() mm: do not show fs mm pc for VM_LOCKONFAULT pages selftests/vm: ksm_functional_tests: fixes for 32bit selftests/vm: cow: fix compile warning on 32bit selftests/vm: madv_populate: fix missing MADV_POPULATE_(READ|WRITE) definitions mm/gup_test: fix PIN_LONGTERM_TEST_READ with highmem mm,thp,rmap: fix races between updates of subpages_mapcount mm: memcg: fix swapcached stat accounting mm: add nodes= arg to memory.reclaim mm: disable top-tier fallback to reclaim on proactive reclaim selftests: cgroup: make sure reclaim target memcg is unprotected selftests: cgroup: refactor proactive reclaim code to reclaim_until() mm: memcg: fix stale protection of reclaim target memcg mm/mmap: properly unaccount memory on mas_preallocate() failure omfs: remove ->writepage jfs: remove ->writepage ...
2022-12-01Docs/admin-guide/mm/damon/usage: document schemes/<s>/tried_regions sysfs ↵SeongJae Park1-3/+42
directory Document 'tried_regions' directory in DAMON sysfs interface usage in the administrator guide. Link: https://lkml.kernel.org/r/20221101220328.95765-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-12-01Docs/admin-guide/mm/damon/usage: fix wrong usage example of init_regions fileSeongJae Park1-5/+6
DAMON debugfs interface assumes the users will write all inputs at once. However, redirecting a string of multiple lines sometimes end up writing line by line. Therefore, the example usage of 'init_regions' file, which writes input as a string of multiple lines can fail. Fix it to use a single line string instead. Also update the description of the usage to not assume users will write inputs in multiple lines. Link: https://lkml.kernel.org/r/20221024174619.15600-3-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Vinicius Petrucci <vpetrucci@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-12-01Docs/admin-guide/mm/damon/usage: describe the rules of sysfs region directoriesSeongJae Park1-0/+3
Patch series "Docs/admin-buide/mm/damon/usage: minor fixes". DAMON usage document contains an unclear description and a wrong usage example. This patchset fixes the two minor problems. This patch (of 2): Target region directories of DAMON sysfs interface should contain no overlap and sorted by the address, but not clearly documented. Actually, a user had an issue[1] due to the poor documentation. Add clear description of it on the usage document. [1] https://lore.kernel.org/damon/CAEZ6=UNUcH2BvJj++OrT=XQLdkidU79wmCO=tantSOB36pPNTg@mail.gmail.com/ Link: https://lkml.kernel.org/r/20221024174619.15600-1-sj@kernel.org Link: https://lkml.kernel.org/r/20221024174619.15600-2-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Reported-by: Vinicius Petrucci <vpetrucci@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-09Docs/admin-guide/mm/zswap: remove a paragraph about zswap being a new featureDavid Heidelberg1-7/+1
Nine years have passed since Linux 3.11. Signed-off-by: David Heidelberg <david@ixit.cz> Link: https://lore.kernel.org/r/20221104122612.14906-1-david@ixit.cz Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-10-11Merge tag 'mm-stable-2022-10-08' of ↵Linus Torvalds9-26/+264
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ...
2022-10-04mm/khugepaged: attempt to map file/shmem-backed pte-mapped THPs by pmdsZach O'Keefe1-1/+8
The main benefit of THPs are that they can be mapped at the pmd level, increasing the likelihood of TLB hit and spending less cycles in page table walks. pte-mapped hugepages - that is - hugepage-aligned compound pages of order HPAGE_PMD_ORDER mapped by ptes - although being contiguous in physical memory, don't have this advantage. In fact, one could argue they are detrimental to system performance overall since they occupy a precious hugepage-aligned/sized region of physical memory that could otherwise be used more effectively. Additionally, pte-mapped hugepages can be the cheapest memory to collapse for khugepaged since no new hugepage allocation or copying of memory contents is necessary - we only need to update the mapping page tables. In the anonymous collapse path, we are able to collapse pte-mapped hugepages (albeit, perhaps suboptimally), but the file/shmem path makes no effort when compound pages (of any order) are encountered. Identify pte-mapped hugepages in the file/shmem collapse path. The final step of which makes a racy check of the value of the pmd to ensure it maps a pte table. This should be fine, since races that result in false-positive (i.e. attempt collapse even though we shouldn't) will fail later in collapse_pte_mapped_thp() once we actually lock mmap_lock and reinspect the pmd value. Races that result in false-negatives (i.e. where we decide to not attempt collapse, but should have) shouldn't be an issue, since in the worst case, we do nothing - which is what we've done up to this point. We make a similar check in retract_page_tables(). If we do think we've found a pte-mapped hugepgae in khugepaged context, attempt to update page tables mapping this hugepage. Note that these collapses still count towards the /sys/kernel/mm/transparent_hugepage/khugepaged/pages_collapsed counter, and if the pte-mapped hugepage was also mapped into multiple process' address spaces, could be incremented for each page table update. Since we increment the counter when a pte-mapped hugepage is successfully added to the list of to-collapse pte-mapped THPs, it's possible that we never actually update the page table either. This is different from how file/shmem pages_collapsed accounting works today where only a successful page cache update is counted (it's also possible here that no page tables are actually changed). Though it incurs some slop, this is preferred to either not accounting for the event at all, or plumbing through data in struct mm_slot on whether to account for the collapse or not. Also note that work still needs to be done to support arbitrary compound pages, and that this should all be converted to using folios. [shy828301@gmail.com: Spelling mistake, update comment, and add Documentation] Link: https://lore.kernel.org/linux-mm/CAHbLzkpHwZxFzjfX9nxVoRhzup8WMjMfyL6Xiq8mZ9M-N3ombw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220907144521.3115321-3-zokeefe@google.com Link: https://lkml.kernel.org/r/20220922224046.1143204-3-zokeefe@google.com Signed-off-by: Zach O'Keefe <zokeefe@google.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Chris Kennelly <ckennelly@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Houghton <jthoughton@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com> Cc: SeongJae Park <sj@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04mm/huge_memory: prevent THP_ZERO_PAGE_ALLOC increased twiceLiu Shixin1-4/+3
A user who reads THP_ZERO_PAGE_ALLOC may be more concerned about the huge zero pages that are really allocated for thp. It is misleading to increase THP_ZERO_PAGE_ALLOC twice if two threads call get_huge_zero_page concurrently. Don't increase the value if the huge page is not really used. Update Documentation/admin-guide/mm/transhuge.rst to suit. Link: https://lkml.kernel.org/r/20220909021653.3371879-1-liushixin2@huawei.com Signed-off-by: Liu Shixin <liushixin2@huawei.com> Cc: Alexander Potapenko <glider@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04Docs/admin-guide/mm/damon/usage: note DAMON debugfs interface deprecation planSeongJae Park1-0/+5
Commit b18402726bd1 ("Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface") announced the DAMON debugfs interface deprecation plan, but it is not so aggressively announced. As the deprecation time is coming, this commit makes the announce more easy to be found by adding the note at the beginning of the DAMON debugfs interface usage document. Link: https://lkml.kernel.org/r/20220909202901.57977-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Yun Levi <ppbuk5246@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04Docs/admin-guide/mm/damon/start: mention the dependency as sysfs instead of ↵SeongJae Park1-10/+3
debugfs 'Getting Started' document of DAMON says DAMON user-space tool, damo[1], is using DAMON debugfs interface, and therefore it needs to ensure debugfs is mounted. However, the latest version of the tool is using DAMON sysfs interface. Moreover, DAMON debugfs interface is going to be deprecated as announced by commit b18402726bd1 ("Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface"). This commit therefore update the document to tell readers about DAMON sysfs interface dependency instead and never mention about debugfs interface, which will be deprecated. [1] https://github.com/awslabs/damo Link: https://lkml.kernel.org/r/20220909202901.57977-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Yun Levi <ppbuk5246@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04Docs/admin-guide/mm/damon: rename the title of the documentSeongJae Park1-3/+3
The title of the DAMON document for admin-guide, 'Monitoring Data Accesses', could confuse readers in some ways. First of all, DAMON is not the only single way for data access monitoring. And the document is for not only the data access monitoring but also data access pattern based memory management optimizations (DAMOS). This commit updates the title to 'DAMON: Data Access MONitor', which more explicitly explains what the document describes. Link: https://lkml.kernel.org/r/20220909202901.57977-5-sj@kernel.org Fixes: c4ba6014aec3 ("Documentation: add documents for DAMON") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Yun Levi <ppbuk5246@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03Merge tag 'docs-6.1' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull documentation updates from Jonathan Corbet: "There's not a huge amount of activity in the docs tree this time around, but a few significant changes even so: - A complete rewriting of the top-level index.rst file, which mostly reflects itself in a redone top page in the HTML-rendered docs. The hope is that the new organization will be a friendlier starting point for both users and developers. - Some math-rendering improvements. - A coding-style.rst update on the use of BUG() and WARN() - A big maintainer-PHP guide update. - Some code-of-conduct updates - More Chinese translation work Plus the usual pile of typo fixes, corrections, and updates" * tag 'docs-6.1' of git://git.lwn.net/linux: (66 commits) checkpatch: warn on usage of VM_BUG_ON() and other BUG variants coding-style.rst: document BUG() and WARN() rules ("do not crash the kernel") Documentation: devres: add missing IO helper Documentation: devres: update IRQ helper Documentation/mm: modify page_referenced to folio_referenced Documentation/CoC: Reflect current CoC interpretation and practices docs/doc-guide: Add documentation on SPHINX_IMGMATH docs: process/5.Posting.rst: clarify use of Reported-by: tag docs, kprobes: Fix the wrong location of Kprobes docs: add a man-pages link to the front page docs: put atomic*.txt and memory-barriers.txt into the core-api book docs: move asm-annotations.rst into core-api docs: remove some index.rst cruft docs: reconfigure the HTML left column docs: Rewrite the front page docs: promote the title of process/index.rst Documentation: devres: add missing SPI helper Documentation: devres: add missing PINCTRL helpers docs: hugetlbpage.rst: fix a typo of hugepage size docs/zh_CN: Add new translation of admin-guide/bootconfig.rst ...
2022-09-27docs: hugetlbpage.rst: fix a typo of hugepage sizeHoi Pok Wu1-1/+1
should be kB instead of Kb Signed-off-by: Hoi Pok Wu <wuhoipok@gmail.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Link: https://lore.kernel.org/r/20220922030645.9719-1-wuhoipok@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27ksm: add profit monitoring documentationxu xin1-0/+36
Add the description of KSM profit and how to determine it separately in system-wide range and inner a single process. Link: https://lkml.kernel.org/r/20220830144003.299870-1-xu.xin16@zte.com.cn Signed-off-by: xu xin <xu.xin16@zte.com.cn> Reviewed-by: Xiaokai Ran <ran.xiaokai@zte.com.cn> Reviewed-by: Yang Yang <yang.yang29@zte.com.cn> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-27mm: multi-gen LRU: admin guideYu Zhao2-0/+163
Add an admin guide. Link: https://lkml.kernel.org/r/20220918080010.2920238-14-yuzhao@google.com Signed-off-by: Yu Zhao <yuzhao@google.com> Acked-by: Brian Geffon <bgeffon@google.com> Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org> Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name> Acked-by: Steven Barrett <steven@liquorix.net> Acked-by: Suleiman Souhlal <suleiman@google.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Tested-by: Daniel Byrne <djbyrne@mtu.edu> Tested-by: Donald Carr <d@chaos-reins.com> Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com> Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru> Tested-by: Shuang Zhai <szhai2@cs.rochester.edu> Tested-by: Sofia Trinh <sofia.trinh@edi.works> Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Barry Song <baohua@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michael Larabel <Michael@MichaelLarabel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-12mm/cma_debug: show complete cma name in debugfs directoriesCharan Teja Kalla1-5/+5
Currently only 12 characters of the cma name is being used as the debug directories where as the cma name can be of length CMA_MAX_NAME(=64) characters. One side problem with this is having 2 cma's with first common 12 characters would end up in trying to create directories with same name and fails with -EEXIST thus can limit cma debug functionality. The 'cma-' prefix is used initially where cma areas don't have any names and are represented by simple integer values. Since now each cma would be having its own name, drop 'cma-' prefix for the cma debug directories as they are clearly evident that they are for cma debug through creating them in /sys/kernel/debug/cma/ path. Link: https://lkml.kernel.org/r/1660223729-22461-1-git-send-email-quic_charante@quicinc.com Signed-off-by: Charan Teja Kalla <quic_charante@quicinc.com> Cc: David Hildenbrand <david@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Pavan Kondeti <quic_pkondeti@quicinc.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-12userfaultfd: update documentation to describe /dev/userfaultfdAxel Rasmussen1-3/+38
Explain the different ways to create a new userfaultfd, and how access control works for each way. [axelrasmussen@google.com: improve wording in documentation, per Mike] Link: https://lkml.kernel.org/r/20220819205201.658693-5-axelrasmussen@google.com Link: https://lkml.kernel.org/r/20220808175614.3885028-5-axelrasmussen@google.com Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Acked-by: Peter Xu <peterx@redhat.com> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry V. Levin <ldv@altlinux.org> Cc: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nadav Amit <namit@vmware.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Yi <yi.zhang@huawei.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-25Docs/admin-guide/mm/damon/usage: fix the example code snipKairui Song1-9/+9
The workflow example code is not working since it got the file names wrong. So fix this. Fixes: b18402726bd1 ("Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface") Reviewed-by: SeongJae Park <sj@kernel.org> Signed-off-by: Kairui Song <kasong@tencent.com> Link: https://lore.kernel.org/r/20220823114053.53305-1-ryncsn@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-08-09mm: hugetlb_vmemmap: introduce the name HVOMuchun Song2-4/+4
It it inconvenient to mention the feature of optimizing vmemmap pages associated with HugeTLB pages when communicating with others since there is no specific or abbreviated name for it when it is first introduced. Let us give it a name HVO (HugeTLB Vmemmap Optimization) from now. This commit also updates the document about "hugetlb_free_vmemmap" by the way discussed in thread [1]. Link: https://lore.kernel.org/all/21aae898-d54d-cc4b-a11f-1bb7fddcfffa@redhat.com/ [1] Link: https://lkml.kernel.org/r/20220628092235.91270-4-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Will Deacon <will@kernel.org> Cc: Xiongchun Duan <duanxiongchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-04Docs/admin-guide/damon: add a document for DAMON_LRU_SORTSeongJae Park2-0/+295
This commit documents the usage of DAMON_LRU_SORT for admins. Link: https://lkml.kernel.org/r/20220613192301.8817-10-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-04Docs/admin-guide/damon/sysfs: document 'LRU_DEPRIO' scheme actionSeongJae Park1-0/+1
This commit documents the 'LRU_DEPRIO' scheme action for DAMON sysfs interface.` Link: https://lkml.kernel.org/r/20220613192301.8817-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-04Docs/admin-guide/damon/sysfs: document 'LRU_PRIO' scheme actionSeongJae Park1-0/+1
This commit documents the 'lru_prio' scheme action for DAMON sysfs interface. Link: https://lkml.kernel.org/r/20220613192301.8817-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>