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2024-05-05mm/hugetlb: assert hugetlb_lock in __hugetlb_cgroup_commit_chargePeter Xu
This is similar to __hugetlb_cgroup_uncharge_folio() where it relies on holding hugetlb_lock. Add the similar assertion like the other one, since it looks like such things may help some day. Link: https://lkml.kernel.org/r/20240417211836.2742593-4-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Mina Almasry <almasrymina@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/sparse: guard the size of mem_section is power of 2Wei Yang
We usually have this check, while commit 2a3cb8baef71 ("mm/sparse: delete old sparse_init and enable new one") missed to take it. Link: https://lkml.kernel.org/r/20240416012559.4536-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05doc: improve the description of __folio_mark_dirtyMatthew Wilcox (Oracle)
Patch series "Improve buffer head documentation", v3. Turn buffer head documentation into its own document, and make many general improvements to the docs. Obviously there is much more that could be done. Tested with make htmldocs. This patch (of 8): I've learned why it's safe to call __folio_mark_dirty() from mark_buffer_dirty() without holding the folio lock, so update the description to explain why. Link: https://lkml.kernel.org/r/20240416031754.4076917-1-willy@infradead.org Link: https://lkml.kernel.org/r/20240416031754.4076917-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Pankaj Raghav <p.raghav@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: remove page_mapcount() usage in stable_tree_search()David Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. If our folio has a stable node, it is a (small) KSM folio -- see folio_stable_node(). Let's use folio_mapcount() in stable_tree_search() instead, which results in no functional change. The mapcount > 1 check is a bit confusing, because that's usually a check for page sharing. Looks like the reason is that we are guaranteed to not exceed ksm_max_page_sharing for the tree KSM folio when merging with that. Let's update the documentation to make that clearer. Link: https://lkml.kernel.org/r/20240416172533.663418-1-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Alex Shi <alexs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: zswap: remove same_filled module paramsYosry Ahmed
These knobs offer more fine-grained control to userspace than needed and directly expose/influence kernel implementation; remove them. For disabling same_filled handling, there is no logical reason to refuse storing same-filled pages more efficiently and opt for compression. Scanning pages for patterns may be an argument, but the page contents will be read into the CPU cache anyway during compression. Also, removing the same_filled handling code does not move the needle significantly in terms of performance anyway [1]. For disabling non_same_filled handling, it was added when the compressed pages in zswap were not being properly charged to memcgs, as workloads could escape the accounting with compression [2]. This is no longer the case after commit f4840ccfca25 ("zswap: memcg accounting"), and using zswap without compression does not make much sense. [1]https://lore.kernel.org/lkml/CAJD7tkaySFP2hBQw4pnZHJJwe3bMdjJ1t9VC2VJd=khn1_TXvA@mail.gmail.com/ [2]https://lore.kernel.org/lkml/19d5cdee-2868-41bd-83d5-6da75d72e940@maciej.szmigiero.name/ [yosryahmed@google.com: remove same_filled_pages from docs] Link: https://lkml.kernel.org/r/ZhxFVggdyvCo79jc@google.com Link: https://lkml.kernel.org/r/20240413022407.785696-5-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev> Cc: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: zswap: move more same-filled pages checks outside of zswap_store()Yosry Ahmed
Currently, zswap_store() checks zswap_same_filled_pages_enabled, kmaps the folio, then calls zswap_is_page_same_filled() to check the folio contents. Move this logic into zswap_is_page_same_filled() as well (and rename it to use 'folio' while we are at it). This makes zswap_store() cleaner, and makes following changes to that logic contained within the helper. While we are at it: - Rename the insert_entry label to store_entry to match xa_store(). - Add comment headers for same-filled functions and the main API functions (load, store, invalidate, swapon, swapoff). No functional change intended. Link: https://lkml.kernel.org/r/20240413022407.785696-4-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Reviewed-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: zswap: refactor limit checking from zswap_store()Yosry Ahmed
Refactor limit and acceptance threshold checking outside of zswap_store(). This code will be moved around in a following patch, so it would be cleaner to move a function call around. Link: https://lkml.kernel.org/r/20240413022407.785696-3-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Reviewed-by: Nhat Pham <nphamcs@gmail.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: zswap: always shrink in zswap_store() if zswap_pool_reached_fullYosry Ahmed
Patch series "zswap same-filled and limit checking cleanups", v3. Miscellaneous cleanups for limit checking and same-filled handling in the store path. This series was broken out of the "zswap: store zero-filled pages more efficiently" series [1]. It contains the cleanups and drops the main functional changes. [1]https://lore.kernel.org/lkml/20240325235018.2028408-1-yosryahmed@google.com/ This patch (of 4): The cleanup code in zswap_store() is not pretty, particularly the 'shrink' label at the bottom that ends up jumping between cleanup labels. Instead of having a dedicated label to shrink the pool, just use zswap_pool_reached_full directly to figure out if the pool needs shrinking. zswap_pool_reached_full should be true if and only if the pool needs shrinking. The only caveat is that the value of zswap_pool_reached_full may be changed by concurrent zswap_store() calls between checking the limit and testing zswap_pool_reached_full in the cleanup code. This is fine because: - If zswap_pool_reached_full was true during limit checking then became false during the cleanup code, then someone else already took care of shrinking the pool and there is no need to queue the worker. That would be a good change. - If zswap_pool_reached_full was false during limit checking then became true during the cleanup code, then someone else hit the limit meanwhile. In this case, both threads will try to queue the worker, but it never gets queued more than once anyway. Also, calling queue_work() multiple times when the limit is hit could already happen today, so this isn't a significant change in any way. Link: https://lkml.kernel.org/r/20240413022407.785696-1-yosryahmed@google.com Link: https://lkml.kernel.org/r/20240413022407.785696-2-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Reviewed-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05userfaultfd: remove WRITE_ONCE when setting folio->index during UFFDIO_MOVESuren Baghdasaryan
When folio is moved with UFFDIO_MOVE it gets locked before the rmap and index are modified. Due to the folio lock being already held, WRITE_ONCE() is not needed when setting the folio index. Remove it. Link: https://lkml.kernel.org/r/20240415020821.1152951-1-surenb@google.com Reported-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Cc: Lokesh Gidra <lokeshgidra@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: page_alloc: allowing mTHP compaction to capture the freed page directlyBaolin Wang
Currently, compaction_capture() does not allow lower-order allocations to directly capture the movable free pages, even though lower-order allocations might also be requesting movable pages, that can lead to more compaction scanning. And, with the enablement of mTHP, such situations will become more common. Thus allowing lower-order (mTHP) allocations of movable page types directly capture the movable free pages can avoid unnecessary compaction scanning, meanwhile that won't pollute the movable pageblock. With testing 1M mTHP compaction, it can be seen that compaction scanning is significantly reduced. mm-unstable patched Ops Compaction pages isolated 116598741.00 120946702.00 Ops Compaction migrate scanned 1764870054.00 1488621550.00 Ops Compaction free scanned 7707879039.00 4986299318.00 Ops Compact scan efficiency 22.90 29.85 Ops Compaction cost 73797.69 72933.48 Link: https://lkml.kernel.org/r/8118a5d66a034736a48433beddaca60ed78577c4.1712892329.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: David Hildenbrand <david@redhat.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: filemap: batch mm counter updating in filemap_map_pages()Kefeng Wang
Like copy_pte_range()/zap_pte_range(), make mm counter batch updating in filemap_map_pages(), since folios type are same(MM_SHMEMPAGES or MM_FILEPAGES) in filemap_map_pages(), only check the first folio type is enough, the 'lat_pagefault -P 1 file' test from lmbench shows 12% improvement, and the percpu_counter_add_batch() is gone from perf flame graph. Link: https://lkml.kernel.org/r/20240412064751.119015-3-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: move mm counter updating out of set_pte_range()Kefeng Wang
Patch series "mm: batch mm counter updating in filemap_map_pages()", v3. Let's batch mm counter updating to accelerate filemap_map_pages(). This patch (of 2): In order to support batch mm counter updating in filemap_map_pages(), move mm counter updating out of set_pte_range(), the folios are file from filemap, and distinguish folios by vmf->flags and vma->vm_flags from another caller finish_fault(). Link: https://lkml.kernel.org/r/20240412064751.119015-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20240412064751.119015-2-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: add per-order mTHP anon_swpout and anon_swpout_fallback countersBarry Song
This helps to display the fragmentation situation of the swapfile, knowing the proportion of how much we haven't split large folios. So far, we only support non-split swapout for anon memory, with the possibility of expanding to shmem in the future. So, we add the "anon" prefix to the counter names. Link: https://lkml.kernel.org/r/20240412114858.407208-3-21cnbao@gmail.com Signed-off-by: Barry Song <v-songbaohua@oppo.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Chris Li <chrisl@kernel.org> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Kairui Song <kasong@tencent.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: add per-order mTHP anon_fault_alloc and anon_fault_fallback countersBarry Song
Patch series "mm: add per-order mTHP alloc and swpout counters", v6. The patchset introduces a framework to facilitate mTHP counters, starting with the allocation and swap-out counters. Currently, only four new nodes are appended to the stats directory for each mTHP size. /sys/kernel/mm/transparent_hugepage/hugepages-<size>/stats anon_fault_alloc anon_fault_fallback anon_fault_fallback_charge anon_swpout anon_swpout_fallback These nodes are crucial for us to monitor the fragmentation levels of both the buddy system and the swap partitions. In the future, we may consider adding additional nodes for further insights. This patch (of 4): Profiling a system blindly with mTHP has become challenging due to the lack of visibility into its operations. Presenting the success rate of mTHP allocations appears to be pressing need. Recently, I've been experiencing significant difficulty debugging performance improvements and regressions without these figures. It's crucial for us to understand the true effectiveness of mTHP in real-world scenarios, especially in systems with fragmented memory. This patch establishes the framework for per-order mTHP counters. It begins by introducing the anon_fault_alloc and anon_fault_fallback counters. Additionally, to maintain consistency with thp_fault_fallback_charge in /proc/vmstat, this patch also tracks anon_fault_fallback_charge when mem_cgroup_charge fails for mTHP. Incorporating additional counters should now be straightforward as well. Link: https://lkml.kernel.org/r/20240412114858.407208-1-21cnbao@gmail.com Link: https://lkml.kernel.org/r/20240412114858.407208-2-21cnbao@gmail.com Signed-off-by: Barry Song <v-songbaohua@oppo.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Chris Li <chrisl@kernel.org> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Kairui Song <kasong@tencent.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/hugetlb: rename dissolve_free_huge_pages() to dissolve_free_hugetlb_folios()Sidhartha Kumar
dissolve_free_huge_pages() only uses folios internally, rename it to dissolve_free_hugetlb_folios() and change the comments which reference it. [akpm@linux-foundation.org: remove unneeded `extern'] Link: https://lkml.kernel.org/r/20240412182139.120871-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/hugetlb: convert dissolve_free_huge_pages() to foliosSidhartha Kumar
Allows us to rename dissolve_free_huge_pages() to dissolve_free_hugetlb_folio(). Convert one caller to pass in a folio directly and use page_folio() to convert the caller in mm/memory-failure. [sidhartha.kumar@oracle.com: remove unneeded `extern'] Link: https://lkml.kernel.org/r/71760ed4-e80d-493a-95ea-2545414b1aba@oracle.com [sidhartha.kumar@oracle.com: v2] Link: https://lkml.kernel.org/r/20240412182139.120871-1-sidhartha.kumar@oracle.com Link: https://lkml.kernel.org/r/20240411164756.261178-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: replace set_page_stable_node by folio_set_stable_nodeAlex Shi (tencent)
Only single page could be reached where we set stable node after write protect, so use folio converted func to replace page's. And remove the unused func set_page_stable_node(). Link: https://lkml.kernel.org/r/20240411061713.1847574-11-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: rename get_ksm_page_flags to ksm_get_folio_flagsDavid Hildenbrand
As we are removing get_ksm_page_flags(), make the flags match the new function name. Link: https://lkml.kernel.org/r/20240411061713.1847574-10-alexs@kernel.org Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Alex Shi <alexs@kernel.org> Reviewed-by: Alex Shi <alexs@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Hugh Dickins <hughd@google.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: convert chain series funcs and replace get_ksm_pageAlex Shi (tencent)
In ksm stable tree all page are single, let's convert them to use and folios as well as stable_tree_insert/stable_tree_search funcs. And replace get_ksm_page() by ksm_get_folio() since there is no more needs. It could save a few compound_head calls. Link: https://lkml.kernel.org/r/20240411061713.1847574-9-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: use folio in write_protect_pageAlex Shi (tencent)
Compound page is checked and skipped before write_protect_page() called, use folio to save a few compound_head checks. Link: https://lkml.kernel.org/r/20240411061713.1847574-8-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: use ksm_get_folio in scan_get_next_rmap_itemAlex Shi (tencent)
Save a compound_head call. Link: https://lkml.kernel.org/r/20240411061713.1847574-7-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: use folio in stable_node_dupAlex Shi (tencent)
Use ksm_get_folio() and save 2 compound_head calls. Link: https://lkml.kernel.org/r/20240411061713.1847574-6-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: use folio in remove_stable_nodeAlex Shi (tencent)
Pages in stable tree are all single normal page, so uses ksm_get_folio() and folio_set_stable_node(), also saves 3 calls to compound_head(). Link: https://lkml.kernel.org/r/20240411061713.1847574-5-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: add folio_set_stable_nodeAlex Shi (tencent)
Turn set_page_stable_node() into a wrapper folio_set_stable_node, and then use it to replace the former. we will merge them together after all place converted to folio. Link: https://lkml.kernel.org/r/20240411061713.1847574-4-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: use folio in remove_rmap_item_from_treeAlex Shi (tencent)
To save 2 compound_head calls. Link: https://lkml.kernel.org/r/20240411061713.1847574-3-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/ksm: add ksm_get_folioAlex Shi (tencent)
Patch series "transfer page to folio in KSM". This is the first part of page to folio transfer on KSM. Since only single page could be stored in KSM, we could safely transfer stable tree pages to folios. This patchset could reduce ksm.o 57kbytes from 2541776 bytes on latest akpm/mm-stable branch with CONFIG_DEBUG_VM enabled. It pass the KSM testing in LTP and kernel selftest. Thanks for Matthew Wilcox and David Hildenbrand's suggestions and comments! This patch (of 10): The ksm only contains single pages, so we could add a new func ksm_get_folio for get_ksm_page to use folio instead of pages to save a couple of compound_head calls. After all caller replaced, get_ksm_page will be removed. Link: https://lkml.kernel.org/r/20240411061713.1847574-1-alexs@kernel.org Link: https://lkml.kernel.org/r/20240411061713.1847574-2-alexs@kernel.org Signed-off-by: Alex Shi (tencent) <alexs@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/debug: print only page mapcount (excluding folio entire mapcount) in ↵David Hildenbrand
__dump_folio() Let's simplify and only print the page mapcount: we already print the large folio mapcount and the entire folio mapcount for large folios separately; that should be sufficient to figure out what's happening. While at it, print the page mapcount also if it had an underflow, filtering out only typed pages. Link: https://lkml.kernel.org/r/20240409192301.907377-18-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/migrate_device: use folio_mapcount() in migrate_vma_check_page()David Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. Let's convert migrate_vma_check_page() to work on a folio internally so we can remove the page_mapcount() usage. Note that we reject any large folios. There is a lot more folio conversion to be had, but that has to wait for another day. No functional change intended. Link: https://lkml.kernel.org/r/20240409192301.907377-15-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/filemap: use folio_mapcount() in filemap_unaccount_folio()David Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. Let's use folio_mapcount() instead of filemap_unaccount_folio(). No functional change intended, because we're only dealing with small folios. Link: https://lkml.kernel.org/r/20240409192301.907377-14-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/migrate: use folio_likely_mapped_shared() in add_page_for_migration()David Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. In add_page_for_migration(), we actually want to check if the folio is mapped shared, to reject such folios. So let's use folio_likely_mapped_shared() instead. For small folios, fully mapped THP, and hugetlb folios, there is no change. For partially mapped, shared THP, we should now do a better job at rejecting such folios. Link: https://lkml.kernel.org/r/20240409192301.907377-12-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/page_alloc: use folio_mapped() in __alloc_contig_migrate_range()David Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. For tracing purposes, we use page_mapcount() in __alloc_contig_migrate_range(). Adding that mapcount to total_mapped sounds strange: total_migrated and total_reclaimed would count each page only once, not multiple times. But then, isolate_migratepages_range() adds each folio only once to the list. So for large folios, we would query the mapcount of the first page of the folio, which doesn't make too much sense for large folios. Let's simply use folio_mapped() * folio_nr_pages(), which makes more sense as nr_migratepages is also incremented by the number of pages in the folio in case of successful migration. Link: https://lkml.kernel.org/r/20240409192301.907377-11-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/memory-failure: use folio_mapcount() in hwpoison_user_mappings()David Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. We can only unmap full folios; page_mapped(), which we check here, is translated to folio_mapped() -- based on folio_mapcount(). So let's print the folio mapcount instead. Link: https://lkml.kernel.org/r/20240409192301.907377-10-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/huge_memory: use folio_mapcount() in zap_huge_pmd() sanity checkDavid Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. Let's similarly check for folio_mapcount() underflows instead of page_mapcount() underflows like we do in zap_present_folio_ptes() now. Instead of the VM_BUG_ON(), we should actually be doing something like print_bad_pte(). For now, let's keep it simple and use WARN_ON_ONCE(), performing that check independently of DEBUG_VM. Link: https://lkml.kernel.org/r/20240409192301.907377-9-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/memory: use folio_mapcount() in zap_present_folio_ptes()David Hildenbrand
We want to limit the use of page_mapcount() to the places where it is absolutely necessary. In zap_present_folio_ptes(), let's simply check the folio mapcount(). If there is some issue, it will underflow at some point either way when unmapping. As indicated already in commit 10ebac4f95e7 ("mm/memory: optimize unmap/zap with PTE-mapped THP"), we already documented "If we ever have a cheap folio_mapcount(), we might just want to check for underflows there.". There is no change for small folios. For large folios, we'll now catch more underflows when batch-unmapping, because instead of only testing the mapcount of the first subpage, we'll test if the folio mapcount underflows. Link: https://lkml.kernel.org/r/20240409192301.907377-8-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: track mapcount of large folios in single valueDavid Hildenbrand
Let's track the mapcount of large folios in a single value. The mapcount of a large folio currently corresponds to the sum of the entire mapcount and all page mapcounts. This sum is what we actually want to know in folio_mapcount() and it is also sufficient for implementing folio_mapped(). With PTE-mapped THP becoming more important and more widely used, we want to avoid looping over all pages of a folio just to obtain the mapcount of large folios. The comment "In the common case, avoid the loop when no pages mapped by PTE" in folio_total_mapcount() does no longer hold for mTHP that are always mapped by PTE. Further, we are planning on using folio_mapcount() more frequently, and might even want to remove page mapcounts for large folios in some kernel configs. Therefore, allow for reading the mapcount of large folios efficiently and atomically without looping over any pages. Maintain the mapcount also for hugetlb pages for simplicity. Use the new mapcount to implement folio_mapcount() and folio_mapped(). Make page_mapped() simply call folio_mapped(). We can now get rid of folio_large_is_mapped(). _nr_pages_mapped is now only used in rmap code and for debugging purposes. Keep folio_nr_pages_mapped() around, but document that its use should be limited to rmap internals and debugging purposes. This change implies one additional atomic add/sub whenever mapping/unmapping (parts of) a large folio. As we now batch RMAP operations for PTE-mapped THP during fork(), during unmap/zap, and when PTE-remapping a PMD-mapped THP, and we adjust the large mapcount for a PTE batch only once, the added overhead in the common case is small. Only when unmapping individual pages of a large folio (e.g., during COW), the overhead might be bigger in comparison, but it's essentially one additional atomic operation. Note that before the new mapcount would overflow, already our refcount would overflow: each mapping requires a folio reference. Extend the focumentation of folio_mapcount(). Link: https://lkml.kernel.org/r/20240409192301.907377-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Yin Fengwei <fengwei.yin@intel.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/rmap: add fast-path for small folios when adding/removing/duplicatingDavid Hildenbrand
Let's add a fast-path for small folios to all relevant rmap functions. Note that only RMAP_LEVEL_PTE applies. This is a preparation for tracking the mapcount of large folios in a single value. Link: https://lkml.kernel.org/r/20240409192301.907377-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Yin Fengwei <fengwei.yin@intel.com> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Chang <richardycc@google.com> Cc: Rich Felker <dalias@libc.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: follow_pte() improvementsDavid Hildenbrand
follow_pte() is now our main function to lookup PTEs in VM_PFNMAP/VM_IO VMAs. Let's perform some more sanity checks to make this exported function harder to abuse. Further, extend the doc a bit, it still focuses on the KVM use case with MMU notifiers. Drop the KVM+follow_pfn() comment, follow_pfn() is no more, and we have other users nowadays. Also extend the doc regarding refcounted pages and the interaction with MMU notifiers. KVM is one example that uses MMU notifiers and can deal with refcounted pages properly. VFIO is one example that doesn't use MMU notifiers, and to prevent use-after-free, rejects refcounted pages: pfn_valid(pfn) && !PageReserved(pfn_to_page(pfn)). Protection changes are less of a concern for users like VFIO: the behavior is similar to longterm-pinning a page, and getting the PTE protection changed afterwards. The primary concern with refcounted pages is use-after-free, which callers should be aware of. Link: https://lkml.kernel.org/r/20240410155527.474777-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Fei Li <fei1.li@intel.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Yonghua Huang <yonghua.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: pass VMA instead of MM to follow_pte()David Hildenbrand
... and centralize the VM_IO/VM_PFNMAP sanity check in there. We'll now also perform these sanity checks for direct follow_pte() invocations. For generic_access_phys(), we might now check multiple times: nothing to worry about, really. Link: https://lkml.kernel.org/r/20240410155527.474777-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Sean Christopherson <seanjc@google.com> [KVM] Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Fei Li <fei1.li@intel.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Yonghua Huang <yonghua.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm,swap: add document about RCU read lock and swapoff interactionHuang Ying
During reviewing a patch to fix the race condition between free_swap_and_cache() and swapoff() [1], it was found that the document about how to prevent racing with swapoff isn't clear enough. Especially RCU read lock can prevent swapoff from freeing data structures. So, the document is added as comments. [1] https://lore.kernel.org/linux-mm/c8fe62d0-78b8-527a-5bef-ee663ccdc37a@huawei.com/ Link: https://lkml.kernel.org/r/20240407065450.498821-1-ying.huang@intel.com Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Hugh Dickins <hughd@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/mmap: make accountable_mapping return boolHao Ge
accountable_mapping() can return bool, so change it. Link: https://lkml.kernel.org/r/20240407063843.804274-1-gehao@kylinos.cn Signed-off-by: Hao Ge <gehao@kylinos.cn> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/mmap: make vma_wants_writenotify return boolHao Ge
vma_wants_writenotify() should return bool, so change it. Link: https://lkml.kernel.org/r/20240407062653.803142-1-gehao@kylinos.cn Signed-off-by: Hao Ge <gehao@kylinos.cn> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05memory tier: create CPUless memory tiers after obtaining HMAT infoHo-Ren (Jack) Chuang
The current implementation treats emulated memory devices, such as CXL1.1 type3 memory, as normal DRAM when they are emulated as normal memory (E820_TYPE_RAM). However, these emulated devices have different characteristics than traditional DRAM, making it important to distinguish them. Thus, we modify the tiered memory initialization process to introduce a delay specifically for CPUless NUMA nodes. This delay ensures that the memory tier initialization for these nodes is deferred until HMAT information is obtained during the boot process. Finally, demotion tables are recalculated at the end. * late_initcall(memory_tier_late_init); Some device drivers may have initialized memory tiers between `memory_tier_init()` and `memory_tier_late_init()`, potentially bringing online memory nodes and configuring memory tiers. They should be excluded in the late init. * Handle cases where there is no HMAT when creating memory tiers There is a scenario where a CPUless node does not provide HMAT information. If no HMAT is specified, it falls back to using the default DRAM tier. * Introduce another new lock `default_dram_perf_lock` for adist calculation In the current implementation, iterating through CPUlist nodes requires holding the `memory_tier_lock`. However, `mt_calc_adistance()` will end up trying to acquire the same lock, leading to a potential deadlock. Therefore, we propose introducing a standalone `default_dram_perf_lock` to protect `default_dram_perf_*`. This approach not only avoids deadlock but also prevents holding a large lock simultaneously. * Upgrade `set_node_memory_tier` to support additional cases, including default DRAM, late CPUless, and hot-plugged initializations. To cover hot-plugged memory nodes, `mt_calc_adistance()` and `mt_find_alloc_memory_type()` are moved into `set_node_memory_tier()` to handle cases where memtype is not initialized and where HMAT information is available. * Introduce `default_memory_types` for those memory types that are not initialized by device drivers. Because late initialized memory and default DRAM memory need to be managed, a default memory type is created for storing all memory types that are not initialized by device drivers and as a fallback. Link: https://lkml.kernel.org/r/20240405000707.2670063-3-horenchuang@bytedance.com Signed-off-by: Ho-Ren (Jack) Chuang <horenchuang@bytedance.com> Signed-off-by: Hao Xiang <hao.xiang@bytedance.com> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Gregory Price <gourry.memverge@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Ravi Jonnalagadda <ravis.opensrc@micron.com> Cc: SeongJae Park <sj@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawie.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05memory tier: dax/kmem: introduce an abstract layer for finding, allocating, ↵Ho-Ren (Jack) Chuang
and putting memory types Patch series "Improved Memory Tier Creation for CPUless NUMA Nodes", v11. When a memory device, such as CXL1.1 type3 memory, is emulated as normal memory (E820_TYPE_RAM), the memory device is indistinguishable from normal DRAM in terms of memory tiering with the current implementation. The current memory tiering assigns all detected normal memory nodes to the same DRAM tier. This results in normal memory devices with different attributions being unable to be assigned to the correct memory tier, leading to the inability to migrate pages between different types of memory. https://lore.kernel.org/linux-mm/PH0PR08MB7955E9F08CCB64F23963B5C3A860A@PH0PR08MB7955.namprd08.prod.outlook.com/T/ This patchset automatically resolves the issues. It delays the initialization of memory tiers for CPUless NUMA nodes until they obtain HMAT information and after all devices are initialized at boot time, eliminating the need for user intervention. If no HMAT is specified, it falls back to using `default_dram_type`. Example usecase: We have CXL memory on the host, and we create VMs with a new system memory device backed by host CXL memory. We inject CXL memory performance attributes through QEMU, and the guest now sees memory nodes with performance attributes in HMAT. With this change, we enable the guest kernel to construct the correct memory tiering for the memory nodes. This patch (of 2): Since different memory devices require finding, allocating, and putting memory types, these common steps are abstracted in this patch, enhancing the scalability and conciseness of the code. Link: https://lkml.kernel.org/r/20240405000707.2670063-1-horenchuang@bytedance.com Link: https://lkml.kernel.org/r/20240405000707.2670063-2-horenchuang@bytedance.com Signed-off-by: Ho-Ren (Jack) Chuang <horenchuang@bytedance.com> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawie.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Gregory Price <gourry.memverge@gmail.com> Cc: Hao Xiang <hao.xiang@bytedance.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Ravi Jonnalagadda <ravis.opensrc@micron.com> Cc: SeongJae Park <sj@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm,page_owner: don't remove __GFP_NOLOCKDEP in add_stack_record_to_listChristoph Hellwig
Otherwise we'll generate false lockdep positives. Link: https://lkml.kernel.org/r/20240429082828.1615986-1-hch@lst.de Fixes: 217b2119b9e2 ("mm,page_owner: implement the tracking of the stacks count") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Darrick J. Wong <djwong@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Marco Elver <elver@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/vmalloc: fix return value of vb_alloc if size is 0Hailong.Liu
vm_map_ram() uses IS_ERR() to validate the return value of vb_alloc(). If vm_map_ram(page, 0, 0) is executed, vb_alloc(0, GFP_KERNEL) would return NULL. In such a case, IS_ERR() cannot handle the return value and lead to kernel panic by vmap_pages_range_noflush() at last. To resolve this issue, return ERR_PTR(-EINVAL) if the size is 0. Link: https://lkml.kernel.org/r/20240426024149.21176-1-hailong.liu@oppo.com Reviewed-by: Barry Song <baohua@kernel.org> Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Hailong.Liu <hailong.liu@oppo.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: use memalloc_nofs_save() in page_cache_ra_order()Kefeng Wang
See commit f2c817bed58d ("mm: use memalloc_nofs_save in readahead path"), ensure that page_cache_ra_order() do not attempt to reclaim file-backed pages too, or it leads to a deadlock, found issue when test ext4 large folio. INFO: task DataXceiver for:7494 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:DataXceiver for state:D stack:0 pid:7494 ppid:1 flags:0x00000200 Call trace: __switch_to+0x14c/0x240 __schedule+0x82c/0xdd0 schedule+0x58/0xf0 io_schedule+0x24/0xa0 __folio_lock+0x130/0x300 migrate_pages_batch+0x378/0x918 migrate_pages+0x350/0x700 compact_zone+0x63c/0xb38 compact_zone_order+0xc0/0x118 try_to_compact_pages+0xb0/0x280 __alloc_pages_direct_compact+0x98/0x248 __alloc_pages+0x510/0x1110 alloc_pages+0x9c/0x130 folio_alloc+0x20/0x78 filemap_alloc_folio+0x8c/0x1b0 page_cache_ra_order+0x174/0x308 ondemand_readahead+0x1c8/0x2b8 page_cache_async_ra+0x68/0xb8 filemap_readahead.isra.0+0x64/0xa8 filemap_get_pages+0x3fc/0x5b0 filemap_splice_read+0xf4/0x280 ext4_file_splice_read+0x2c/0x48 [ext4] vfs_splice_read.part.0+0xa8/0x118 splice_direct_to_actor+0xbc/0x288 do_splice_direct+0x9c/0x108 do_sendfile+0x328/0x468 __arm64_sys_sendfile64+0x8c/0x148 invoke_syscall+0x4c/0x118 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x4c/0x1f8 el0t_64_sync_handler+0xc0/0xc8 el0t_64_sync+0x188/0x190 Link: https://lkml.kernel.org/r/20240426112938.124740-1-wangkefeng.wang@huawei.com Fixes: 793917d997df ("mm/readahead: Add large folio readahead") Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Zhang Yi <yi.zhang@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: page_owner: fix wrong information in dump_page_ownerManinder Singh
With commit ea4b5b33bf8a ("mm,page_owner: update metadata for tail pages"), new API __update_page_owner_handle was introduced and arguemnt was passed in wrong order from __set_page_owner and thus page_owner is giving wrong data. [ 15.982420] page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL), pid 80, tgid -1210279584 (insmod), ts 80, free_ts 0 Fixing the same. Correct output: [ 14.556482] page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL), pid 80, tgid 80 (insmod), ts 14552004992, free_ts 0 Link: https://lkml.kernel.org/r/20240424111838.3782931-1-hariom1.p@samsung.com Fixes: ea4b5b33bf8a ("mm,page_owner: update metadata for tail pages") Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Signed-off-by: Hariom Panthi <hariom1.p@samsung.com> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Christoph Hellwig <hch@infradead.org> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Rohit Thapliyal <r.thapliyal@samsung.com> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-02swapon(2): open swap with O_EXCLAl Viro
... eliminating the need to reopen block devices so they could be exclusively held. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-05-02swapon(2)/swapoff(2): don't bother with block sizeAl Viro
once upon a time that used to matter; these days we do swap IO for swap devices at the level that doesn't give a damn about block size, buffer_head or anything of that sort - just attach the page to bio, set the location and size (the latter to PAGE_SIZE) and feed into queue. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-05-02mm/slub: remove the check for NULL kmalloc_cachesHyunmin Lee
If the same size kmalloc cache already exists, it should not be created again. So there is the check for NULL kmalloc_caches before calling the kmalloc creation function. However, new_kmalloc_cache() itself checks NULL kmalloc_cahces before cache creation. Therefore, the NULL check is not necessary in this function. Signed-off-by: Hyunmin Lee <hyunminlr@gmail.com> Co-developed-by: Jeungwoo Yoo <casionwoo@gmail.com> Signed-off-by: Jeungwoo Yoo <casionwoo@gmail.com> Co-developed-by: Sangyun Kim <sangyun.kim@snu.ac.kr> Signed-off-by: Sangyun Kim <sangyun.kim@snu.ac.kr> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com> Reviewed-by: Christoph Lameter <cl@linux.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>