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2024-11-06mm, kasan, kmsan: instrument copy_from/to_kernel_nofaultSabyrzhan Tasbolatov
Instrument copy_from_kernel_nofault() with KMSAN for uninitialized kernel memory check and copy_to_kernel_nofault() with KASAN, KCSAN to detect the memory corruption. syzbot reported that bpf_probe_read_kernel() kernel helper triggered KASAN report via kasan_check_range() which is not the expected behaviour as copy_from_kernel_nofault() is meant to be a non-faulting helper. Solution is, suggested by Marco Elver, to replace KASAN, KCSAN check in copy_from_kernel_nofault() with KMSAN detection of copying uninitilaized kernel memory. In copy_to_kernel_nofault() we can retain instrument_write() explicitly for the memory corruption instrumentation. copy_to_kernel_nofault() is tested on x86_64 and arm64 with CONFIG_KASAN_SW_TAGS. On arm64 with CONFIG_KASAN_HW_TAGS, kunit test currently fails. Need more clarification on it. [akpm@linux-foundation.org: fix comment layout, per checkpatch Link: https://lore.kernel.org/linux-mm/CANpmjNMAVFzqnCZhEity9cjiqQ9CVN1X7qeeeAp_6yKjwKo8iw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20241011035310.2982017-1-snovitoll@gmail.com Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com> Reviewed-by: Marco Elver <elver@google.com> Reported-by: syzbot+61123a5daeb9f7454599@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=61123a5daeb9f7454599 Reported-by: Andrey Konovalov <andreyknvl@gmail.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=210505 Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> [KASAN] Tested-by: Andrey Konovalov <andreyknvl@gmail.com> [KASAN] Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: simplify mas_push_node()Wei Yang
When count is not 0, we know head is valid. So we can put the assignment in if (count) instead of checking the head pointer again. Also count represents current total, we can assign the new total by increasing the count by one. Link: https://lkml.kernel.org/r/20241015120746.15850-4-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: total is not changed for nomem_one caseWei Yang
If it jumps to nomem_one, the total allocated number is not changed. So we don't need to adjust it. For the nomem_bulk case, we know there is a valid mas->alloc. So we don't need to do the check. Link: https://lkml.kernel.org/r/20241015120746.15850-3-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: clear request_count for new allocated oneWei Yang
Patch series "maple_tree: simplify mas_push_node()", v2. When count is not 0, we know head is valid. So we can put the assignment in if (count) instead of checking the head pointer again. Also count represents current total, we can assign the new total by increasing the count by one. This patch (of 3): If this is not a new allocated one, the request_count has already been cleared in mas_set_alloc_req(). Link: https://lkml.kernel.org/r/20241015120746.15850-1-richard.weiyang@gmail.com Link: https://lkml.kernel.org/r/20241015120746.15850-2-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: root node could be handled by !p_slot tooWei Yang
For a root node, mte_parent_slot() return 0, this exactly fits the following !p_slot check. So we can remove the special handling for root node. Link: https://lkml.kernel.org/r/20240913063128.27391-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: add some alloc node test caseJiazi Li
Add some maple_tree alloc node tese case. Link: https://lkml.kernel.org/r/20240626160631.3636515-2-Liam.Howlett@oracle.com Signed-off-by: Jiazi Li <jqqlijiazi@gmail.com> Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Suggested-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Wei Yang <richard.weiyang@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: fix alloc node fail issueJiazi Li
In the following code, the second call to the mas_node_count will return -ENOMEM: mas_node_count(mas, MAPLE_ALLOC_SLOTS + 1); mas_node_count(mas, MAPLE_ALLOC_SLOTS * 2 + 2); This is because there may be some full maple_alloc node in current maple state. Use full maple_alloc node will make max_req equal to 0. And it leads to mt_alloc_bulk return 0. As a result, mas_node_count set mas.node to MA_ERROR(-ENOMEM). Find a non-full maple_alloc node, and if necessary, use this non-full node in the next while loop. Link: https://lkml.kernel.org/r/20240626160631.3636515-1-Liam.Howlett@oracle.com Fixes: 54a611b60590 ("Maple Tree: add new data structure") Signed-off-by: Jiazi Li <jqqlijiazi@gmail.com> Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Suggested-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm/vmstat: defer the refresh_zone_stat_thresholds after all CPUs bringupSaurabh Sengar
refresh_zone_stat_thresholds function has two loops which is expensive for higher number of CPUs and NUMA nodes. Below is the rough estimation of total iterations done by these loops based on number of NUMA and CPUs. Total number of iterations: nCPU * 2 * Numa * mCPU Where: nCPU = total number of CPUs Numa = total number of NUMA nodes mCPU = mean value of total CPUs (e.g., 512 for 1024 total CPUs) For the system under test with 16 NUMA nodes and 1024 CPUs, this results in a substantial increase in the number of loop iterations during boot-up when NUMA is enabled: No NUMA = 1024*2*1*512 = 1,048,576 : Here refresh_zone_stat_thresholds takes around 224 ms total for all the CPUs in the system under test. 16 NUMA = 1024*2*16*512 = 16,777,216 : Here refresh_zone_stat_thresholds takes around 4.5 seconds total for all the CPUs in the system under test. Calling this for each CPU is expensive when there are large number of CPUs along with multiple NUMAs. Fix this by deferring refresh_zone_stat_thresholds to be called later at once when all the secondary CPUs are up. Also, register the DYN hooks to keep the existing hotplug functionality intact. Link: https://lkml.kernel.org/r/1723443220-20623-1-git-send-email-ssengar@linux.microsoft.com Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com> Acked-by: Christoph Lameter <cl@linux.com> Reviewed-by: Srivatsa S. Bhat (Microsoft) <srivatsa@csail.mit.edu> Cc: Saurabh Singh Sengar <ssengar@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06vmscan: add a vmscan event for reclaim_pagesJaewon Kim
reclaim_folio_list uses a dummy reclaim_stat and is not being used. To know the memory stat, add a new trace event. This is useful how how many pages are not reclaimed or why. This is an example: mm_vmscan_reclaim_pages: nid=0 nr_scanned=112 nr_reclaimed=112 nr_dirty=0 nr_writeback=0 nr_congested=0 nr_immediate=0 nr_activate_anon=0 nr_activate_file=0 nr_ref_keep=0 nr_unmap_fail=0 Currently reclaim_folio_list is only called by reclaim_pages, and reclaim_pages is used by damon and madvise. In the latest Android, reclaim_pages is also used by shmem to reclaim all pages in a address_space. [jaewon31.kim@samsung.com: use sc.nr_scanned rather than new counting] Link: https://lkml.kernel.org/r/20241016143227.961162-1-jaewon31.kim@samsung.com Link: https://lkml.kernel.org/r/20241011124928.1224813-1-jaewon31.kim@samsung.com Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Jaewon Kim <jaewon31.kim@samsung.com> Cc: Kalesh Singh <kaleshsingh@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: avoid zeroing user movable page twice with init_on_alloc=1Zi Yan
Commit 6471384af2a6 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options") forces allocated page to be zeroed in post_alloc_hook() when init_on_alloc=1. For order-0 folios, if arch does not define vma_alloc_zeroed_movable_folio(), the default implementation again zeros the page return from the buddy allocator. So the page is zeroed twice. Fix it by passing __GFP_ZERO instead to avoid double page zeroing. At the moment, s390,arm64,x86,alpha,m68k are not impacted since they define their own vma_alloc_zeroed_movable_folio(). For >0 order folios (mTHP and PMD THP), folio_zero_user() is called to zero the folio again. Fix it by calling folio_zero_user() only if init_on_alloc is set. All arch are impacted. Add alloc_zeroed() helper to encapsulate the init_on_alloc check. [ziy@nvidia.com: comment fixes, per David] Link: https://lkml.kernel.org/r/97DB52E1-C594-49B5-9736-89AC302FAB01@nvidia.com Link: https://lkml.kernel.org/r/20241011150304.709590-1-ziy@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm/zswap: avoid touching XArray for unnecessary invalidationKairui Song
zswap_invalidation simply calls xa_erase, which acquires the Xarray lock first, then does a look up. This has a higher overhead even if zswap is not used or the tree is empty. So instead, do a very lightweight xa_empty check first, if there is nothing to erase, don't touch the lock or the tree. Using xa_empty rather than zswap_never_enabled is more helpful as it cover both case where zswap wes never used or the particular range doesn't have any zswap entry. And it's safe as the swap slot should be currently pinned by caller with HAS_CACHE. Sequential SWAP in/out tests with zswap disabled showed a minor performance gain, SWAP in of zero page with zswap enabled also showed a performance gain. (swapout is basically unchanged so only test one case): Swapout of 2G zero page using brd as SWAP, zswap disabled (total time, 4 testrun, +0.1%): Before: 1705013 us 1703119 us 1704335 us 1705848 us. After: 1703579 us 1710640 us 1703625 us 1708699 us. Swapin of 2G zero page using brd as SWAP, zswap disabled (total time, 4 testrun, -3.5%): Before: 1912312 us 1915692 us 1905837 us 1912706 us. After: 1845354 us 1849691 us 1845868 us 1841828 us. Swapin of 2G zero page using brd as SWAP, zswap enabled (total time, 4 testrun, -3.3%): Before: 1897994 us 1894681 us 1899982 us 1898333 us After: 1835894 us 1834113 us 1832047 us 1833125 us Swapin of 2G random page using brd as SWAP, zswap enabled (total time, 4 testrun, -0.1%): Before: 4519747 us 4431078 us 4430185 us 4439999 us After: 4492176 us 4437796 us 4434612 us 4434289 us And the performance is very slightly better or unchanged for build kernel test with zswap enabled or disabled. Build Linux Kernel with defconfig and -j32 in 1G memory cgroup, using brd SWAP, zswap disabled (sys time in seconds, 6 testrun, -0.1%): Before: 1648.83 1653.52 1666.34 1665.95 1663.06 1656.67 After: 1651.36 1661.89 1645.70 1657.45 1662.07 1652.83 Build Linux Kernel with defconfig and -j32 in 2G memory cgroup, using brd SWAP zswap enabled (sys time in seconds, 6 testrun, -0.3%): Before: 1240.25 1254.06 1246.77 1265.92 1244.23 1227.74 After: 1226.41 1218.21 1249.12 1249.13 1244.39 1233.01 Link: https://lkml.kernel.org/r/20241011171950.62684-1-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Acked-by: Yosry Ahmed <yosryahmed@google.com> Cc: Barry Song <v-songbaohua@oppo.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chris Li <chrisl@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: refactor mas_wr_store_type()Sidhartha Kumar
In mas_wr_store_type(), we check if new_end < mt_slots[wr_mas->type]. If this check fails, we know that ,after this, new_end is >= mt_min_slots. Checking this again when we detect a wr_node_store later in the function is reduntant. Because this check is part of an OR statement, the statement will always evaluate to true, therefore we can just get rid of it. We also refactor mas_wr_store_type() to return the store type rather than set it directly as it greatly cleans up the function. Link: https://lkml.kernel.org/r/20241011214451.7286-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha <sidhartha.kumar@oracle.com> Suggested-by: Liam Howlett <liam.howlett@oracle.com> Suggested-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Liam Howlett <liam.howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm/hugetlb: perform vmemmap optimization batchly for specific node allocationsuhua
When HVO is enabled and huge page memory allocs are made, the freed memory can be aggregated into higher order memory in the following paths, which facilitates further allocs for higher order memory. echo 200000 > /proc/sys/vm/nr_hugepages echo 200000 > /sys/devices/system/node/node*/hugepages/hugepages-2048kB/nr_hugepages grub default_hugepagesz=2M hugepagesz=2M hugepages=200000 Currently not support for releasing aggregations to higher order in the following way, which will releasing to lower order. grub: default_hugepagesz=2M hugepagesz=2M hugepages=0:100000,1:100000 This patch supports the release of huge page optimizations aggregates to higher order memory. eg: cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-xxx ... default_hugepagesz=2M hugepagesz=2M hugepages=0:100000,1:100000 Before: Free pages count per migrate type at order 0 1 2 3 4 5 6 7 8 9 10 ... Node 0, zone Normal, type Unmovable 55282 97039 99307 0 1 1 0 1 1 1 0 Node 0, zone Normal, type Movable 25 11 345 87 48 21 2 20 9 3 75061 Node 0, zone Normal, type Reclaimable 4 2 2 4 3 0 2 1 1 1 0 Node 0, zone Normal, type HighAtomic 0 0 0 0 0 0 0 0 0 0 0 ... Free pages count per migrate type at order 0 1 2 3 4 5 6 7 8 9 10 Node 1, zone Normal, type Unmovable 98888 99650 99679 2 3 1 2 2 2 0 0 Node 1, zone Normal, type Movable 1 1 0 1 1 0 1 0 1 1 75937 Node 1, zone Normal, type Reclaimable 0 0 0 0 0 0 0 0 0 0 0 Node 1, zone Normal, type HighAtomic 0 0 0 0 0 0 0 0 0 0 0 After: Free pages count per migrate type at order 0 1 2 3 4 5 6 7 8 9 10 ... Node 0, zone Normal, type Unmovable 152 158 37 2 2 0 3 4 2 6 717 Node 0, zone Normal, type Movable 1 37 53 3 55 49 16 6 2 1 75000 Node 0, zone Normal, type Reclaimable 1 4 3 1 2 1 1 1 1 1 0 Node 0, zone Normal, type HighAtomic 0 0 0 0 0 0 0 0 0 0 0 ... Free pages count per migrate type at order 0 1 2 3 4 5 6 7 8 9 10 Node 1, zone Normal, type Unmovable 5 3 2 1 3 4 2 2 2 0 779 Node 1, zone Normal, type Movable 1 0 1 1 1 0 1 0 1 1 75849 Node 1, zone Normal, type Reclaimable 0 0 0 0 0 0 0 0 0 0 0 Node 1, zone Normal, type HighAtomic 0 0 0 0 0 0 0 0 0 0 0 Link: https://lkml.kernel.org/r/20241012070802.1876-1-suhua1@kingsoft.com Signed-off-by: suhua <suhua1@kingsoft.com> Reviewed-by: Muchun Song <muchun.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06memcg: add tracing for memcg stat updatesShakeel Butt
The memcg stats are maintained in rstat infrastructure which provides very fast updates side and reasonable read side. However memcg added plethora of stats and made the read side, which is cgroup rstat flush, very slow. To solve that, threshold was added in the memcg stats read side i.e. no need to flush the stats if updates are within the threshold. This threshold based improvement worked for sometime but more stats were added to memcg and also the read codepath was getting triggered in the performance sensitive paths which made threshold based ratelimiting ineffective. We need more visibility into the hot and cold stats i.e. stats with a lot of updates. Let's add trace to get that visibility. [shakeel.butt@linux.dev: use unsigned long type for memcg_rstat_events, per Yosry] Link: https://lkml.kernel.org/r/20241015213721.3804209-1-shakeel.butt@linux.dev Link: https://lkml.kernel.org/r/20241010003550.3695245-1-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: T.J. Mercier <tjmercier@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: JP Kobryn <inwardvessel@gmail.com> Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: remove unused hugepage for vma_alloc_folio()Kefeng Wang
The hugepage parameter was deprecated since commit ddc1a5cbc05d ("mempolicy: alloc_pages_mpol() for NUMA policy without vma"), for PMD-sized THP, it still tries only preferred node if possible in vma_alloc_folio() by checking the order of the folio allocation. Link: https://lkml.kernel.org/r/20241010061556.1846751-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Barry Song <baohua@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: add pcp high_min high_max to proc zoneinfoMengEn Sun
When we do not set percpu_pagelist_high_fraction the kernel will compute the pcp high_min/max by itself, which makes it hard to determine the current high_min/max values. So output the pcp high_min/max values to /proc/zoneinfo. Link: https://lkml.kernel.org/r/20241010120935.656619-1-mengensun@tencent.com Signed-off-by: MengEn Sun <mengensun@tencent.com> Reviewed-by: Jinliang Zheng <alexjlzheng@tencent.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm/kmemleak: fix typo in object_no_scan() commentMike Rapoport (Microsoft)
Replace "corresponding to the give pointer" with "corresponding to the given pointer" Link: https://lkml.kernel.org/r/20241010155439.554416-1-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06kaslr: rename physmem_end and PHYSMEM_END to direct_map_physmem_endJohn Hubbard
For clarity. It's increasingly hard to reason about the code, when KASLR is moving around the boundaries. In this case where KASLR is randomizing the location of the kernel image within physical memory, the maximum number of address bits for physical memory has not changed. What has changed is the ending address of memory that is allowed to be directly mapped by the kernel. Let's name the variable, and the associated macro accordingly. Also, enhance the comment above the direct_map_physmem_end definition, to further clarify how this all works. Link: https://lkml.kernel.org/r/20241009025024.89813-1-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alistair Popple <apopple@nvidia.com> Cc: Jordan Niethe <jniethe@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06zram: do not open-code comp priority 0Sergey Senozhatsky
A cosmetic change: do not open-code compression priority 0, use ZRAM_PRIMARY_COMP instead. Link: https://lkml.kernel.org/r/20241009042908.750260-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: allocate THP on hugezeropage wp-faultDev Jain
Introduce do_huge_zero_wp_pmd() to handle wp-fault on a hugezeropage and replace it with a PMD-mapped THP. Remember to flush TLB entry corresponding to the hugezeropage. In case of failure, fallback to splitting the PMD. Link: https://lkml.kernel.org/r/20241008061746.285961-3-dev.jain@arm.com Signed-off-by: Dev Jain <dev.jain@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Barry Song <baohua@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Lameter <cl@gentwo.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: abstract THP allocationDev Jain
Patch series "Do not shatter hugezeropage on wp-fault", v7. It was observed at [1] and [2] that the current kernel behaviour of shattering a hugezeropage is inconsistent and suboptimal. For a VMA with a THP allowable order, when we write-fault on it, the kernel installs a PMD-mapped THP. On the other hand, if we first get a read fault, we get a PMD pointing to the hugezeropage; subsequent write will trigger a write-protection fault, shattering the hugezeropage into one writable page, and all the other PTEs write-protected. The conclusion being, as compared to the case of a single write-fault, applications have to suffer 512 extra page faults if they were to use the VMA as such, plus we get the overhead of khugepaged trying to replace that area with a THP anyway. Instead, replace the hugezeropage with a THP on wp-fault. [1]: https://lore.kernel.org/all/3743d7e1-0b79-4eaf-82d5-d1ca29fe347d@arm.com/ [2]: https://lore.kernel.org/all/1cfae0c0-96a2-4308-9c62-f7a640520242@arm.com/ This patch (of 2): In preparation for the second patch, abstract away the THP allocation logic present in the create_huge_pmd() path, which corresponds to the faulting case when no page is present. There should be no functional change as a result of applying this patch, except that, as David notes at [1], a PMD-aligned address should be passed to update_mmu_cache_pmd(). [1]: https://lore.kernel.org/all/ddd3fcd2-48b3-4170-bcaa-2fe66e093f43@redhat.com/ Link: https://lkml.kernel.org/r/20241008061746.285961-1-dev.jain@arm.com Link: https://lkml.kernel.org/r/20241008061746.285961-2-dev.jain@arm.com Signed-off-by: Dev Jain <dev.jain@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Barry Song <baohua@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Lameter <cl@gentwo.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06MAINTAINERS: mailmap: update Alexey Klimov's email addressAlexey Klimov
My new address is alexey.klimov@linaro.org Link: https://lkml.kernel.org/r/20241008132353.68767-1-alexey.klimov@linaro.org Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm/memory.c: remove stray newline at top of fileAndrew Morton
Fixes: d61ea1cb0095 ("userfaultfd: UFFD_FEATURE_WP_ASYNC") Reported-by: Jeongjun Park <aha310510@gmail.com> Closes: https://lkml.kernel.org/r/20241007065307.4158-1-aha310510@gmail.com Cc: Muhammad Usama Anjum <usama.anjum@collabora.com> Cc: Peter Xu <peterx@redhat.com> Cc: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06percpu: fix data race with pcpu_nr_empty_pop_pagesDennis Zhou
Fixes the data race by moving the read to be behind the pcpu_lock. This is okay because the code (initially) above it will not increase the empty populated page count because it is populating backing pages that already have allocations served out of them. Link: https://lkml.kernel.org/r/20241008001942.8114-1-dennis@kernel.org Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202407191651.f24e499d-oliver.sang@intel.com Signed-off-by: Dennis Zhou <dennis@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: consolidate common checks in hugetlb_get_unmapped_areaOscar Salvador
prepare_hugepage_range() performs almost the same checks for all architectures that define it, with the exception of mips and loongarch that also check for overflows. The rest checks for the addr and len to be properly aligned, so we can move that to hugetlb_get_unmapped_area() and get rid of a fair amount of duplicated code. [akpm@linux-foundation.org: remove now-unused local] Link: https://lore.kernel.org/oe-kbuild-all/202410081210.uNLbf3Jk-lkp@intel.com/ Link: https://lkml.kernel.org/r/20241007075037.267650-10-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/s390: clean up hugetlb definitionsOscar Salvador
s390 redefines functions that are already defined (and the same) in include/asm-generic/hugetlb.h. Do as the other architectures: 1) include include/asm-generic/hugetlb.h 2) drop the already defined functions in the generic hugetlb.h and 3) use the __HAVE_ARCH_HUGE_* macros to define our own. This gets rid of quite some code. Link: https://lkml.kernel.org/r/20241007075037.267650-9-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: drop hugetlb_get_unmapped_area{_*} functionsOscar Salvador
Hugetlb mappings are now handled through normal channels just like any other mapping, so we no longer need hugetlb_get_unmapped_area* specific functions. Link: https://lkml.kernel.org/r/20241007075037.267650-8-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: make hugetlb mappings go through mm_get_unmapped_area_vmflagsOscar Salvador
Hugetlb mappings will no longer be special cased but rather go through the generic mm_get_unmapped_area_vmflags function. For that to happen, let us remove the .get_unmapped_area from hugetlbfs_file_operations struct, and hint __get_unmapped_area that it should not send hugetlb mappings through thp_get_unmapped_area_vmflags but through mm_get_unmapped_area_vmflags. Create also a function called hugetlb_mmap_check_and_align() where a couple of safety checks are being done and the addr is aligned to the huge page size. Otherwise we will have to do this in every single function, which duplicates quite a lot of code. Link: https://lkml.kernel.org/r/20241007075037.267650-7-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/powerpc: teach book3s64 arch_get_unmapped_area{_topdown} to handle ↵Oscar Salvador
hugetlb mappings We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area{_topdown} to handle those. Reshuffle file_to_psize() definition so arch_get_unmapped_area{_topdown} can make use of it. Link: https://lkml.kernel.org/r/20241007075037.267650-6-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/sparc: teach arch_get_unmapped_area{_topdown} to handle hugetlb mappingsOscar Salvador
We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area{_topdown} to handle those. sparc specific hugetlb function does not set info.align_offset, and does not care about adjusting the align_mask for MAP_SHARED cases, so the same here for compatibility. Link: https://lkml.kernel.org/r/20241007075037.267650-5-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/x86: teach arch_get_unmapped_area_vmflags to handle hugetlb mappingsOscar Salvador
We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area_{topdown_}vmflags to handle those. x86 specific hugetlb function does not set either info.start_gap or info.align_offset so the same here for compatibility. Link: https://lkml.kernel.org/r/20241007075037.267650-4-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06arch/s390: teach arch_get_unmapped_area{_topdown} to handle hugetlb mappingsOscar Salvador
We want to stop special casing hugetlb mappings and make them go through generic channels, so teach arch_get_unmapped_area{_topdown} to handle those. s390 specific hugetlb function does not set info.align_offset, so do the same here for compatibility. Link: https://lkml.kernel.org/r/20241007075037.267650-3-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm/mmap: teach generic_get_unmapped_area{_topdown} to handle hugetlb mappingsOscar Salvador
Patch series "Unify hugetlb into arch_get_unmapped_area functions", v4. This is an attempt to get rid of a fair amount of duplicated code wrt. hugetlb and *get_unmapped_area* functions. HugeTLB registers a .get_unmapped_area function which gets called from __get_unmapped_area(). hugetlb_get_unmapped_area() is defined by a bunch of architectures and it also has a generic definition for those that do not define it. Short-long story is that there is a ton of duplicated code between specific hugetlb *_get_unmapped_area_* functions and mm-core functions, so we can do better by teaching arch_get_unmapped_area* functions how to deal with hugetlb mappings. Note that not a lot of things need to be taught though. hugetlb_get_unmapped_area, that gets called for hugetlb mappings, runs some sanity checks prior to calling mm_get_unmapped_area_vmflags(), so we do not need to that down the road in the respective {generic,arch}_get_unmapped_area* functions. More information can be found in the respective patches. LTP mmapstress hugetlb selftests were ran succesfully on: This patch (of 9): We want to stop special casing hugetlb mappings and make them go through generic channels, so teach generic_get_unmapped_area{_topdown} to handle those. The main difference is that we set info.align_mask for huge mappings. Link: https://lkml.kernel.org/r/20241007075037.267650-1-osalvador@suse.de Link: https://lkml.kernel.org/r/20241007075037.267650-2-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: remove misleading 'unlikely' hint in vms_gather_munmap_vmas()Breno Leitao
Performance analysis using branch annotation on a fleet of 200 hosts running web servers revealed that the 'unlikely' hint in vms_gather_munmap_vmas() was 100% consistently incorrect. In all observed cases, the branch behavior contradicted the hint. Remove the 'unlikely' qualifier from the condition checking 'vms->uf'. By doing so, we allow the compiler to make optimization decisions based on its own heuristics and profiling data, rather than relying on a static hint that has proven to be inaccurate in real-world scenarios. Link: https://lkml.kernel.org/r/20241004164832.218681-1-leitao@debian.org Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06maple_tree: do not hash pointers on dump in debug modeLorenzo Stoakes
Many maple tree values output when an mt_validate() or equivalent hits an issue utilise tagged pointers, most notably parent nodes. Also some pivots/slots contain meaningful values, output as pointers, such as the index of the last entry with data for example. All pointer values such as this are destroyed by kernel pointer hashing rendering the debug output obtained from CONFIG_DEBUG_VM_MAPLE_TREE considerably less usable. Update this code to output the raw pointers using %px rather than %p when CONFIG_DEBUG_VM_MAPLE_TREE is defined. This is justified, as the use of this configuration flag indicates that this is a test environment. Userland does not understand %px, so use %p there. In an abundance of caution, if CONFIG_DEBUG_VM_MAPLE_TREE is not set, also use %p to avoid exposing raw kernel pointers except when we are positive a testing mode is enabled. This was inspired by the investigation performed in recent debugging efforts around a maple tree regression [0] where kernel pointer tagging had to be disabled in order to obtain truly meaningful and useful data. [0]:https://lore.kernel.org/all/20241001023402.3374-1-spasswolf@web.de/ Link: https://lkml.kernel.org/r/20241007115335.90104-1-lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm/truncate: reset xa_has_values flag on each iterationShakeel Butt
Currently mapping_try_invalidate() and invalidate_inode_pages2_range() traverses the xarray in batches and then for each batch, maintains and sets the flag named xa_has_values if the batch has a shadow entry to clear the entries at the end of the iteration. However they forgot to reset the flag at the end of the iteration which causes them to always try to clear the shadow entries in the subsequent iterations where there might not be any shadow entries. Fix this inefficiency. Link: https://lkml.kernel.org/r/20241002225150.2334504-1-shakeel.butt@linux.dev Fixes: 61c663e020d2 ("mm/truncate: batch-clear shadow entries") Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Yu Zhao <yuzhao@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: swap: make some count_mthp_stat() call-sites be THP-agnostic.Kanchana P Sridhar
In commit 246d3aa3e531 ("mm: cleanup count_mthp_stat() definition"), Ryan Roberts has pointed out the merits of mm code that does not require THP, to be compile-able without requiring THP ifdefs. As a step in that direction, he has moved count_mthp_stat() to be always defined, resolving to a no-op if THP is not defined. Barry Song referred me to Ryan's commit when I was working on the "mm: zswap swap-out of large folios" patch-series [1]. This patch propagates the benefits of the above change to page_io.c and vmscan.c. As a result, there is one less reason to have the ifdef THP in these code sections. [1]: https://patchwork.kernel.org/project/linux-mm/list/?series=894347 Link: https://lkml.kernel.org/r/20241002225822.9006-1-kanchana.p.sridhar@intel.com Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> Reviewed-by: Nhat Pham <nphamcs@gmail.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Wajdi Feghali <wajdi.k.feghali@intel.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Barry Song <21cnbao@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: move set_pxd_safe() helpers from generic to platformAnshuman Khandual
set_pxd_safe() helpers that serve a specific purpose for both x86 and riscv platforms, do not need to be in the common memory code. Otherwise they just unnecessarily make the common API more complicated. This moves the helpers from common code to platform instead. Link: https://lkml.kernel.org/r/20241003044842.246016-1-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06gup: convert FOLL_TOUCH case in follow_page_pte() to folioMatthew Wilcox (Oracle)
We already have the folio here, so just use it, removing three hidden calls to compound_head(). Link: https://lkml.kernel.org/r/20241002151403.1345296-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: remove PageKsm()Matthew Wilcox (Oracle)
All callers have been converted to use folio_test_ksm() or PageAnonNotKsm(), so we can remove this wrapper. Link: https://lkml.kernel.org/r/20241002152533.1350629-6-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alex Shi <alexs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06mm: add PageAnonNotKsm()Matthew Wilcox (Oracle)
Check that this anonymous page is really anonymous, not anonymous-or-KSM. This optimises the debug check, but its real purpose is to remove the last two users of PageKsm(). [willy@infradead.org: fix assertions] Link: https://lkml.kernel.org/r/ZwApWPER7caIA_N3@casper.infradead.org Link: https://lkml.kernel.org/r/20241002152533.1350629-5-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alex Shi <alexs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06ksm: convert should_skip_rmap_item() to take a folioMatthew Wilcox (Oracle)
Remove a call to PageKSM() by passing the folio containing tmp_page to should_skip_rmap_item. Removes a hidden call to compound_head(). Link: https://lkml.kernel.org/r/20241002152533.1350629-4-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alex Shi <alexs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06ksm: convert cmp_and_merge_page() to use a folioMatthew Wilcox (Oracle)
By making try_to_merge_two_pages() and stable_tree_search() return a folio, we can replace kpage with kfolio. This replaces 7 calls to compound_head() with one. [cuigaosheng1@huawei.com: add IS_ERR_OR_NULL check for stable_tree_search()] Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com> Link: https://lkml.kernel.org/r/20241002152533.1350629-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alex Shi <alexs@kernel.org> Cc: Gaosheng Cui <cuigaosheng1@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06ksm: use a folio in try_to_merge_one_page()Matthew Wilcox (Oracle)
Patch series "Remove PageKsm()". The KSM flag is almost always tested on the folio rather than on the page. This series removes the final users of PageKsm() and makes the flag only This patch (of 5): It is safe to use a folio here because all callers took a refcount on this page. The one wrinkle is that we have to recalculate the value of folio after splitting the page, since it has probably changed. Replaces nine calls to compound_head() with one. Link: https://lkml.kernel.org/r/20241002152533.1350629-1-willy@infradead.org Link: https://lkml.kernel.org/r/20241002152533.1350629-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Alex Shi <alexs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05selftests/damon/access_memory_even: remove unused variablesBa Jing
By reading the code, I found these variables are never referenced in the code. Just remove them. Link: https://lkml.kernel.org/r/20240924021426.1980-1-bajing@cmss.chinamobile.com Signed-off-by: Ba Jing <bajing@cmss.chinamobile.com> Reviewed-by: SeongJae Park <sj@kernel.org> Reviewed-by: Dev Jain <dev.jain@arm.com> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05mm/cma: fix useless return in void functionPintu Kumar
There is a unnecessary return statement at the end of void function cma_activate_area. This can be dropped. While at it, also fix another warning related to unsigned. These are reported by checkpatch as well. WARNING: Prefer 'unsigned int' to bare use of 'unsigned' +unsigned cma_area_count; WARNING: void function return statements are not generally useful + return; +} Link: https://lkml.kernel.org/r/20240927181637.19941-1-quic_pintu@quicinc.com Signed-off-by: Pintu Kumar <quic_pintu@quicinc.com> Cc: Pintu Agarwal <pintu.ping@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05mm: optimize invalidation of shadow entriesShakeel Butt
The kernel invalidates the page cache in batches of PAGEVEC_SIZE. For each batch, it traverses the page cache tree and collects the entries (folio and shadow entries) in the struct folio_batch. For the shadow entries present in the folio_batch, it has to traverse the page cache tree for each individual entry to remove them. This patch optimize this by removing them in a single tree traversal. To evaluate the changes, we created 200GiB file on a fuse fs and in a memcg. We created the shadow entries by triggering reclaim through memory.reclaim in that specific memcg and measure the simple fadvise(DONTNEED) operation. # time xfs_io -c 'fadvise -d 0 ${file_size}' file time (sec) Without 5.12 +- 0.061 With-patch 4.19 +- 0.086 (18.16% decrease) Link: https://lkml.kernel.org/r/20240925224716.2904498-3-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Chris Mason <clm@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Omar Sandoval <osandov@osandov.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05mm: optimize truncation of shadow entriesShakeel Butt
Patch series "mm: optimize shadow entries removal", v2. Some of our production workloads which processes a large amount of data spends considerable amount of CPUs on truncation and invalidation of large sized files (100s of GiBs of size). Tracing the operations showed that most of the time is in shadow entries removal. This patch series optimizes the truncation and invalidation operations. This patch (of 2): The kernel truncates the page cache in batches of PAGEVEC_SIZE. For each batch, it traverses the page cache tree and collects the entries (folio and shadow entries) in the struct folio_batch. For the shadow entries present in the folio_batch, it has to traverse the page cache tree for each individual entry to remove them. This patch optimize this by removing them in a single tree traversal. On large machines in our production which run workloads manipulating large amount of data, we have observed that a large amount of CPUs are spent on truncation of very large files (100s of GiBs file sizes). More specifically most of time was spent on shadow entries cleanup, so optimizing the shadow entries cleanup, even a little bit, has good impact. To evaluate the changes, we created 200GiB file on a fuse fs and in a memcg. We created the shadow entries by triggering reclaim through memory.reclaim in that specific memcg and measure the simple truncation operation. # time truncate -s 0 file time (sec) Without 5.164 +- 0.059 With-patch 4.21 +- 0.066 (18.47% decrease) Link: https://lkml.kernel.org/r/20240925224716.2904498-1-shakeel.butt@linux.dev Link: https://lkml.kernel.org/r/20240925224716.2904498-2-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Chris Mason <clm@fb.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Omar Sandoval <osandov@osandov.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05mm: migrate LRU_REFS_MASK bits in folio_migrate_flagsZhaoyang Huang
Bits of LRU_REFS_MASK are not inherited during migration which lead to new folio start from tier0 when MGLRU enabled. Try to bring as much bits of folio->flags as possible since compaction and alloc_contig_range which introduce migration do happen at times. Link: https://lkml.kernel.org/r/20240926050647.5653-1-zhaoyang.huang@unisoc.com Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com> Suggested-by: Yu Zhao <yuzhao@google.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-05mm: pgtable: remove pte_offset_map_nolock()Qi Zheng
Now no users are using the pte_offset_map_nolock(), remove it. Link: https://lkml.kernel.org/r/d04f9bbbcde048fb6ffa6f2bdbc6f9b22d5286f9.1727332572.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Muchun Song <muchun.song@linux.dev> Acked-by: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>