kernel/linux.git/include/linux/vmstat.h, branch v6.12.80

mm/vmstat: fix a W=1 clang compiler warning

2025-01-02T09:34:10+00:00

[ Upstream commit 30c2de0a267c04046d89e678cc0067a9cfb455df ] Fix the following clang compiler warning that is reported if the kernel is built with W=1: ./include/linux/vmstat.h:518:36: error: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Werror,-Wenum-enum-conversion] 518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_" | ~~~~~~~~~~~ ^ ~~~ Link: https://lkml.kernel.org/r/20241212213126.1269116-1-bvanassche@acm.org Fixes: 9d7ea9a297e6 ("mm/vmstat: add helpers to get vmstat item names for each enum type") Signed-off-by: Bart Van Assche Cc: Konstantin Khlebnikov Cc: Nathan Chancellor Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

mm,memcg: provide per-cgroup counters for NUMA balancing operations

2024-09-04T04:15:36+00:00

The ability to observe the demotion and promotion decisions made by the kernel on a per-cgroup basis is important for monitoring and tuning containerized workloads on machines equipped with tiered memory. Different containers in the system may experience drastically different memory tiering actions that cannot be distinguished from the global counters alone. For example, a container running a workload that has a much hotter memory accesses will likely see more promotions and fewer demotions, potentially depriving a colocated container of top tier memory to such an extent that its performance degrades unacceptably. For another example, some containers may exhibit longer periods between data reuse, causing much more numa_hint_faults than numa_pages_migrated. In this case, tuning hot_threshold_ms may be appropriate, but the signal can easily be lost if only global counters are available. In the long term, we hope to introduce per-cgroup control of promotion and demotion actions to implement memory placement policies in tiering. This patch set adds seven counters to memory.stat in a cgroup: numa_pages_migrated, numa_pte_updates, numa_hint_faults, pgdemote_kswapd, pgdemote_khugepaged, pgdemote_direct and pgpromote_success. pgdemote_* and pgpromote_success are also available in memory.numa_stat. count_memcg_events_mm() is added to count multiple event occurrences at once, and get_mem_cgroup_from_folio() is added because we need to get a reference to the memcg of a folio before it's migrated to track numa_pages_migrated. The accounting of PGDEMOTE_* is moved to shrink_inactive_list() before being changed to per-cgroup. [kaiyang2@cs.cmu.edu: add documentation of the memcg counters in cgroup-v2.rst] Link: https://lkml.kernel.org/r/20240814235122.252309-1-kaiyang2@cs.cmu.edu Link: https://lkml.kernel.org/r/20240814174227.30639-1-kaiyang2@cs.cmu.edu Signed-off-by: Kaiyang Zhao Cc: David Rientjes Cc: Johannes Weiner Cc: Michal Hocko Cc: Muchun Song Cc: Roman Gushchin Cc: Shakeel Butt Cc: Wei Xu Signed-off-by: Andrew Morton

mm: don't account memmap per-node

2024-08-16T05:16:14+00:00

Fix invalid access to pgdat during hot-remove operation: ndctl users reported a GPF when trying to destroy a namespace: $ ndctl destroy-namespace all -r all -f Segmentation fault dmesg: Oops: general protection fault, probably for non-canonical address 0xdffffc0000005650: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: probably user-memory-access in range [0x000000000002b280-0x000000000002b287] CPU: 26 UID: 0 PID: 1868 Comm: ndctl Not tainted 6.11.0-rc1 #1 Hardware name: Dell Inc. PowerEdge R640/08HT8T, BIOS 2.20.1 09/13/2023 RIP: 0010:mod_node_page_state+0x2a/0x110 cxl-test users report a GPF when trying to unload the test module: $ modrpobe -r cxl-test dmesg BUG: unable to handle page fault for address: 0000000000004200 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 UID: 0 PID: 1076 Comm: modprobe Tainted: G O N 6.11.0-rc1 #197 Tainted: [O]=OOT_MODULE, [N]=TEST Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/15 RIP: 0010:mod_node_page_state+0x6/0x90 Currently, when memory is hot-plugged or hot-removed the accounting is done based on the assumption that memmap is allocated from the same node as the hot-plugged/hot-removed memory, which is not always the case. In addition, there are challenges with keeping the node id of the memory that is being remove to the time when memmap accounting is actually performed: since this is done after remove_pfn_range_from_zone(), and also after remove_memory_block_devices(). Meaning that we cannot use pgdat nor walking though memblocks to get the nid. Given all of that, account the memmap overhead system wide instead. For this we are going to be using global atomic counters, but given that memmap size is rarely modified, and normally is only modified either during early boot when there is only one CPU, or under a hotplug global mutex lock, therefore there is no need for per-cpu optimizations. Also, while we are here rename nr_memmap to nr_memmap_pages, and nr_memmap_boot to nr_memmap_boot_pages to be self explanatory that the units are in page count. [pasha.tatashin@soleen.com: address a few nits from David Hildenbrand] Link: https://lkml.kernel.org/r/20240809191020.1142142-4-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240809191020.1142142-4-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240808213437.682006-4-pasha.tatashin@soleen.com Fixes: 15995a352474 ("mm: report per-page metadata information") Signed-off-by: Pasha Tatashin Reported-by: Yi Zhang Closes: https://lore.kernel.org/linux-cxl/CAHj4cs9Ax1=CoJkgBGP_+sNu6-6=6v=_L-ZBZY0bVLD3wUWZQg@mail.gmail.com Reported-by: Alison Schofield Closes: https://lore.kernel.org/linux-mm/Zq0tPd2h6alFz8XF@aschofie-mobl2/#t Tested-by: Dan Williams Tested-by: Alison Schofield Acked-by: David Hildenbrand Acked-by: David Rientjes Tested-by: Yi Zhang Cc: Domenico Cerasuolo Cc: Fan Ni Cc: Joel Granados Cc: Johannes Weiner Cc: Li Zhijian Cc: Matthew Wilcox (Oracle) Cc: Mike Rapoport Cc: Muchun Song Cc: Nhat Pham Cc: Sourav Panda Cc: Vlastimil Babka Cc: Yosry Ahmed Signed-off-by: Andrew Morton

mm: add system wide stats items category

2024-08-16T05:16:14+00:00

/proc/vmstat contains events and stats, events can only grow, but stats can grow and shrink. vmstat has the following: ------------------------- NR_VM_ZONE_STAT_ITEMS: per-zone stats NR_VM_NUMA_EVENT_ITEMS: per-numa events NR_VM_NODE_STAT_ITEMS: per-numa stats NR_VM_WRITEBACK_STAT_ITEMS: system-wide background-writeback and dirty-throttling tresholds. NR_VM_EVENT_ITEMS: system-wide events ------------------------- Rename NR_VM_WRITEBACK_STAT_ITEMS to NR_VM_STAT_ITEMS, to track the system-wide stats, we are going to add per-page metadata stats to this category in the next patch. Also delete unused writeback_stat_name(). Link: https://lkml.kernel.org/r/20240809191020.1142142-2-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240808213437.682006-3-pasha.tatashin@soleen.com Fixes: 15995a352474 ("mm: report per-page metadata information") Signed-off-by: Pasha Tatashin Suggested-by: Yosry Ahmed Tested-by: Alison Schofield Acked-by: David Hildenbrand Acked-by: David Rientjes Cc: Dan Williams Cc: Domenico Cerasuolo Cc: Joel Granados Cc: Johannes Weiner Cc: Li Zhijian Cc: Matthew Wilcox (Oracle) Cc: Mike Rapoport Cc: Muchun Song Cc: Nhat Pham Cc: Sourav Panda Cc: Vlastimil Babka Cc: Yi Zhang Cc: Fan Ni Signed-off-by: Andrew Morton

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24T18:59:29+00:00

const qualify the struct ctl_table argument in the proc_handler function signatures. This is a prerequisite to moving the static ctl_table structs into .rodata data which will ensure that proc_handler function pointers cannot be modified. This patch has been generated by the following coccinelle script: ``` virtual patch @r1@ identifier ctl, write, buffer, lenp, ppos; identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)"; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos); @r2@ identifier func, ctl, write, buffer, lenp, ppos; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos) { ... } @r3@ identifier func; @@ int func( - struct ctl_table * + const struct ctl_table * ,int , void *, size_t *, loff_t *); @r4@ identifier func, ctl; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int , void *, size_t *, loff_t *); @r5@ identifier func, write, buffer, lenp, ppos; @@ int func( - struct ctl_table * + const struct ctl_table * ,int write, void *buffer, size_t *lenp, loff_t *ppos); ``` * Code formatting was adjusted in xfs_sysctl.c to comply with code conventions. The xfs_stats_clear_proc_handler, xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where adjusted. * The ctl_table argument in proc_watchdog_common was const qualified. This is called from a proc_handler itself and is calling back into another proc_handler, making it necessary to change it as part of the proc_handler migration. Co-developed-by: Thomas Weißschuh Signed-off-by: Thomas Weißschuh Co-developed-by: Joel Granados Signed-off-by: Joel Granados

mm: report per-page metadata information

2024-07-04T02:30:09+00:00

Today, we do not have any observability of per-page metadata and how much it takes away from the machine capacity. Thus, we want to describe the amount of memory that is going towards per-page metadata, which can vary depending on build configuration, machine architecture, and system use. This patch adds 2 fields to /proc/vmstat that can used as shown below: Accounting per-page metadata allocated by boot-allocator: /proc/vmstat:nr_memmap_boot * PAGE_SIZE Accounting per-page metadata allocated by buddy-allocator: /proc/vmstat:nr_memmap * PAGE_SIZE Accounting total Perpage metadata allocated on the machine: (/proc/vmstat:nr_memmap_boot + /proc/vmstat:nr_memmap) * PAGE_SIZE Utility for userspace: Observability: Describe the amount of memory overhead that is going to per-page metadata on the system at any given time since this overhead is not currently observable. Debugging: Tracking the changes or absolute value in struct pages can help detect anomalies as they can be correlated with other metrics in the machine (e.g., memtotal, number of huge pages, etc). page_ext overheads: Some kernel features such as page_owner page_table_check that use page_ext can be optionally enabled via kernel parameters. Having the total per-page metadata information helps users precisely measure impact. Furthermore, page-metadata metrics will reflect the amount of struct pages reliquished (or overhead reduced) when hugetlbfs pages are reserved which will vary depending on whether hugetlb vmemmap optimization is enabled or not. For background and results see: lore.kernel.org/all/20240220214558.3377482-1-souravpanda@google.com Link: https://lkml.kernel.org/r/20240605222751.1406125-1-souravpanda@google.com Signed-off-by: Sourav Panda Acked-by: David Rientjes Reviewed-by: Pasha Tatashin Cc: Alexey Dobriyan Cc: Bjorn Helgaas Cc: Chen Linxuan Cc: David Hildenbrand Cc: Greg Kroah-Hartman Cc: Ivan Babrou Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Kefeng Wang Cc: Kirill A. Shutemov Cc: Liam R. Howlett Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Muchun Song Cc: "Rafael J. Wysocki" Cc: Randy Dunlap Cc: Shakeel Butt Cc: Suren Baghdasaryan Cc: Tomas Mudrunka Cc: Vlastimil Babka Cc: Wei Xu Cc: Yang Yang Cc: Yosry Ahmed Signed-off-by: Andrew Morton

mm: page_alloc: consolidate free page accounting

2024-04-26T03:56:04+00:00

Free page accounting currently happens a bit too high up the call stack, where it has to deal with guard pages, compaction capturing, block stealing and even page isolation. This is subtle and fragile, and makes it difficult to hack on the code. Now that type violations on the freelists have been fixed, push the accounting down to where pages enter and leave the freelist. [hannes@cmpxchg.org: undo unrelated drive-by line wrap] Link: https://lkml.kernel.org/r/20240327185736.GA7597@cmpxchg.org [hannes@cmpxchg.org: remove unused page parameter from account_freepages()] Link: https://lkml.kernel.org/r/20240327185831.GB7597@cmpxchg.org [baolin.wang@linux.alibaba.com: fix free page accounting] Link: https://lkml.kernel.org/r/a2a48baca69f103aa431fd201f8a06e3b95e203d.1712648441.git.baolin.wang@linux.alibaba.com [andriy.shevchenko@linux.intel.com: avoid defining unused function] Link: https://lkml.kernel.org/r/20240423161506.2637177-1-andriy.shevchenko@linux.intel.com Link: https://lkml.kernel.org/r/20240320180429.678181-11-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Signed-off-by: Andy Shevchenko Signed-off-by: Baolin Wang Reviewed-by: Vlastimil Babka Tested-by: Baolin Wang Cc: David Hildenbrand Cc: "Huang, Ying" Cc: Mel Gorman Cc: Zi Yan Signed-off-by: Andrew Morton

mm/memcontrol: remove __mod_lruvec_page_state()

2024-01-05T18:17:47+00:00

There are no more callers of __mod_lruvec_page_state(), so convert the implementation to __lruvec_stat_mod_folio(), removing two calls to compound_head() (one explicit, one hidden inside page_memcg()). Link: https://lkml.kernel.org/r/20231228085748.1083901-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Zi Yan Acked-by: Shakeel Butt Reviewed-by: Vlastimil Babka Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Johannes Weiner Signed-off-by: Andrew Morton

mm: remove inc/dec lruvec page state functions

2024-01-05T18:17:45+00:00

Patch series "Remove some lruvec page accounting functions", v2. Some functions are now unused; remove them. Make __mod_lruvec_page_state() unused and then remove it. This patch (of 6): All callers of these have been converted to their folio equivalents. Link: https://lkml.kernel.org/r/20231228085748.1083901-1-willy@infradead.org Link: https://lkml.kernel.org/r/20231228085748.1083901-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Johannes Weiner Cc: Vlastimil Babka Signed-off-by: Andrew Morton

mm: introduce per-VMA lock statistics

2023-04-06T03:03:01+00:00

Add a new CONFIG_PER_VMA_LOCK_STATS config option to dump extra statistics about handling page fault under VMA lock. Link: https://lkml.kernel.org/r/20230227173632.3292573-29-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton