user/sven/linux.git/include/linux/mmzone.h, branch v6.6.5

mm: remove obsolete comment above struct per_cpu_pages

2023-08-18T17:12:12Z

Since commit 01b44456a7aa ("mm/page_alloc: replace local_lock with normal spinlock"), per_cpu_pages is protected by normal spinlock. Remove the obsolete comment as it's not that helpful. Link: https://lkml.kernel.org/r/20230706092441.1574950-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Signed-off-by: Andrew Morton

Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2023-06-28T17:28:11Z

Pull mm updates from Andrew Morton: - Yosry Ahmed brought back some cgroup v1 stats in OOM logs - Yosry has also eliminated cgroup's atomic rstat flushing - Nhat Pham adds the new cachestat() syscall. It provides userspace with the ability to query pagecache status - a similar concept to mincore() but more powerful and with improved usability - Mel Gorman provides more optimizations for compaction, reducing the prevalence of page rescanning - Lorenzo Stoakes has done some maintanance work on the get_user_pages() interface - Liam Howlett continues with cleanups and maintenance work to the maple tree code. Peng Zhang also does some work on maple tree - Johannes Weiner has done some cleanup work on the compaction code - David Hildenbrand has contributed additional selftests for get_user_pages() - Thomas Gleixner has contributed some maintenance and optimization work for the vmalloc code - Baolin Wang has provided some compaction cleanups, - SeongJae Park continues maintenance work on the DAMON code - Huang Ying has done some maintenance on the swap code's usage of device refcounting - Christoph Hellwig has some cleanups for the filemap/directio code - Ryan Roberts provides two patch series which yield some rationalization of the kernel's access to pte entries - use the provided APIs rather than open-coding accesses - Lorenzo Stoakes has some fixes to the interaction between pagecache and directio access to file mappings - John Hubbard has a series of fixes to the MM selftesting code - ZhangPeng continues the folio conversion campaign - Hugh Dickins has been working on the pagetable handling code, mainly with a view to reducing the load on the mmap_lock - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment from 128 to 8 - Domenico Cerasuolo has improved the zswap reclaim mechanism by reorganizing the LRU management - Matthew Wilcox provides some fixups to make gfs2 work better with the buffer_head code - Vishal Moola also has done some folio conversion work - Matthew Wilcox has removed the remnants of the pagevec code - their functionality is migrated over to struct folio_batch * tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits) mm/hugetlb: remove hugetlb_set_page_subpool() mm: nommu: correct the range of mmap_sem_read_lock in task_mem() hugetlb: revert use of page_cache_next_miss() Revert "page cache: fix page_cache_next/prev_miss off by one" mm/vmscan: fix root proactive reclaim unthrottling unbalanced node mm: memcg: rename and document global_reclaim() mm: kill [add|del]_page_to_lru_list() mm: compaction: convert to use a folio in isolate_migratepages_block() mm: zswap: fix double invalidate with exclusive loads mm: remove unnecessary pagevec includes mm: remove references to pagevec mm: rename invalidate_mapping_pagevec to mapping_try_invalidate mm: remove struct pagevec net: convert sunrpc from pagevec to folio_batch i915: convert i915_gpu_error to use a folio_batch pagevec: rename fbatch_count() mm: remove check_move_unevictable_pages() drm: convert drm_gem_put_pages() to use a folio_batch i915: convert shmem_sg_free_table() to use a folio_batch scatterlist: add sg_set_folio() ...

mm/vmscan: fix root proactive reclaim unthrottling unbalanced node

2023-06-23T23:59:32Z

When memory.reclaim was introduced, it became the first case where cgroup_reclaim() is true for the root cgroup. Johannes concluded [1] that for most cases this is okay, except for one case. Historically, kswapd would throttle reclaim on a node if a lot of pages marked for reclaim are under writeback (aka the node is congested). This occurred by setting LRUVEC_CONGESTED bit in lruvec->flags. The bit would be cleared when the node is balanced. Similarly, cgroup reclaim would set the same bit when an lruvec is congested, and clear it on the way out of reclaim (to throttle local reclaimers). Before the introduction of memory.reclaim, the root memcg was the only target of kswapd reclaim, and non-root memcgs were the only targets of cgroup reclaim, so they would never interfere. Using the same bit for both was fine. After memory.reclaim, it is possible for cgroup reclaim on the root cgroup to clear the bit set by kswapd. This would result in reclaim on the node to be unthrottled before the node is balanced. Fix this by introducing separate bits for cgroup-level and node-level congestion. kswapd can unthrottle an lruvec that is marked as congested by cgroup reclaim (as the entire node should no longer be congested), but not vice versa (to prevent premature unthrottling before the entire node is balanced). [1]https://lore.kernel.org/lkml/20230405200150.GA35884@cmpxchg.org/ Link: https://lkml.kernel.org/r/20230621023101.432780-1-yosryahmed@google.com Signed-off-by: Yosry Ahmed Reported-by: Johannes Weiner Closes: https://lore.kernel.org/lkml/20230405200150.GA35884@cmpxchg.org/ Cc: Michal Hocko Cc: Roman Gushchin Cc: Shakeel Butt Cc: Muchun Song Cc: Yu Zhao Signed-off-by: Andrew Morton

mmzone: introduce folio_migratetype()

2023-06-19T23:19:34Z

Introduce folio_migratetype() as a folio equivalent for get_pageblock_migratetype(). This function intends to return the migratetype the folio is located in, hence the name choice. Link: https://lkml.kernel.org/r/20230614021312.34085-3-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) Reviewed-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton

mmzone: introduce folio_is_zone_movable()

2023-06-19T23:19:34Z

Patch series "Replace is_longterm_pinnable_page()", v2. This patchset introduces some more helper functions for the folio conversions, and converts all callers of is_longterm_pinnable_page() to use folios. This patch (of 5): Introduce folio_is_zone_movable() to act as a folio equivalent for is_zone_movable_page(). This is to assist in later folio conversions. Link: https://lkml.kernel.org/r/20230614021312.34085-1-vishal.moola@gmail.com Link: https://lkml.kernel.org/r/20230614021312.34085-2-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) Reviewed-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton

mm: multi-gen LRU: cleanup lru_gen_soft_reclaim()

2023-06-09T23:25:39Z

lru_gen_soft_reclaim() gets the lruvec from the memcg and node ID to keep a cleaner interface on the caller side. Link: https://lkml.kernel.org/r/20230522112058.2965866-2-talumbau@google.com Signed-off-by: T.J. Alumbaugh Reviewed-by: Yuanchu Xie Cc: David Hildenbrand Cc: Yu Zhao Signed-off-by: Andrew Morton

mm: page_alloc: move sysctls into it own fils

2023-06-09T23:25:24Z

This moves all page alloc related sysctls to its own file, as part of the kernel/sysctl.c spring cleaning, also move some functions declarations from mm.h into internal.h. Link: https://lkml.kernel.org/r/20230516063821.121844-13-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Cc: David Hildenbrand Cc: "Huang, Ying" Cc: Iurii Zaikin Cc: Kees Cook Cc: Len Brown Cc: Luis Chamberlain Cc: Mike Rapoport (IBM) Cc: Oscar Salvador Cc: Pavel Machek Cc: Rafael J. Wysocki Signed-off-by: Andrew Morton

mm: Add support for unaccepted memory

2023-06-06T14:38:22Z

UEFI Specification version 2.9 introduces the concept of memory acceptance. Some Virtual Machine platforms, such as Intel TDX or AMD SEV-SNP, require memory to be accepted before it can be used by the guest. Accepting happens via a protocol specific to the Virtual Machine platform. There are several ways the kernel can deal with unaccepted memory: 1. Accept all the memory during boot. It is easy to implement and it doesn't have runtime cost once the system is booted. The downside is very long boot time. Accept can be parallelized to multiple CPUs to keep it manageable (i.e. via DEFERRED_STRUCT_PAGE_INIT), but it tends to saturate memory bandwidth and does not scale beyond the point. 2. Accept a block of memory on the first use. It requires more infrastructure and changes in page allocator to make it work, but it provides good boot time. On-demand memory accept means latency spikes every time kernel steps onto a new memory block. The spikes will go away once workload data set size gets stabilized or all memory gets accepted. 3. Accept all memory in background. Introduce a thread (or multiple) that gets memory accepted proactively. It will minimize time the system experience latency spikes on memory allocation while keeping low boot time. This approach cannot function on its own. It is an extension of #2: background memory acceptance requires functional scheduler, but the page allocator may need to tap into unaccepted memory before that. The downside of the approach is that these threads also steal CPU cycles and memory bandwidth from the user's workload and may hurt user experience. Implement #1 and #2 for now. #2 is the default. Some workloads may want to use #1 with accept_memory=eager in kernel command line. #3 can be implemented later based on user's demands. Support of unaccepted memory requires a few changes in core-mm code: - memblock accepts memory on allocation. It serves early boot memory allocations and doesn't limit them to pre-accepted pool of memory. - page allocator accepts memory on the first allocation of the page. When kernel runs out of accepted memory, it accepts memory until the high watermark is reached. It helps to minimize fragmentation. EFI code will provide two helpers if the platform supports unaccepted memory: - accept_memory() makes a range of physical addresses accepted. - range_contains_unaccepted_memory() checks anything within the range of physical addresses requires acceptance. Signed-off-by: Kirill A. Shutemov Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Vlastimil Babka Acked-by: Mike Rapoport # memblock Link: https://lore.kernel.org/r/20230606142637.5171-2-kirill.shutemov@linux.intel.com

mm: Multi-gen LRU: remove wait_event_killable()

2023-04-18T23:30:11Z

Android 14 and later default to MGLRU [1] and field telemetry showed occasional long tail latency (>100ms) in the reclaim path. Tracing revealed priority inversion in the reclaim path. In try_to_inc_max_seq(), when high priority tasks were blocked on wait_event_killable(), the preemption of the low priority task to call wake_up_all() caused those high priority tasks to wait longer than necessary. In general, this problem is not different from others of its kind, e.g., one caused by mutex_lock(). However, it is specific to MGLRU because it introduced the new wait queue lruvec->mm_state.wait. The purpose of this new wait queue is to avoid the thundering herd problem. If many direct reclaimers rush into try_to_inc_max_seq(), only one can succeed, i.e., the one to wake up the rest, and the rest who failed might cause premature OOM kills if they do not wait. So far there is no evidence supporting this scenario, based on how often the wait has been hit. And this begs the question how useful the wait queue is in practice. Based on Minchan's recommendation, which is in line with his commit 6d4675e60135 ("mm: don't be stuck to rmap lock on reclaim path") and the rest of the MGLRU code which also uses trylock when possible, remove the wait queue. [1] https://android-review.googlesource.com/q/I7ed7fbfd6ef9ce10053347528125dd98c39e50bf Link: https://lkml.kernel.org/r/20230413214326.2147568-1-kaleshsingh@google.com Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks") Signed-off-by: Kalesh Singh Suggested-by: Minchan Kim Reported-by: Wei Wang Acked-by: Yu Zhao Cc: Minchan Kim Cc: Jan Alexander Steffens (heftig) Cc: Oleksandr Natalenko Cc: Suleiman Souhlal Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

mm: move free_area_empty() to mm/internal.h

2023-04-18T23:29:47Z

The free_area_empty() helper is only used inside mm/ so move it there to reduce noise in include/linux/mmzone.h Link: https://lkml.kernel.org/r/20230326160215.2674531-1-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Suggested-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton