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* zsmalloc: make zspage chain size configurableSergey Senozhatsky2023-02-021-8/+4
| | | | | | | | | | | | | | | | Remove hard coded limit on the maximum number of physical pages per-zspage. This will allow tuning of zsmalloc pool as zspage chain size changes `pages per-zspage` and `objects per-zspage` characteristics of size classes which also affects size classes clustering (the way size classes are merged). Link: https://lkml.kernel.org/r/20230118005210.2814763-4-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: skip chain size calculation for pow_of_2 classesSergey Senozhatsky2023-02-021-0/+3
| | | | | | | | | | | If a class size is power of 2 then it wastes no memory and the best configuration is 1 physical page per-zspage. Link: https://lkml.kernel.org/r/20230118005210.2814763-3-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: rework zspage chain size selectionSergey Senozhatsky2023-02-021-37/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "zsmalloc: make zspage chain size configurable". Computers are bad at division. We currently decide the best zspage chain size (max number of physical pages per-zspage) by looking at a `used percentage` value. This is not enough as we lose precision during usage percentage calculations For example, let's look at size class 208: pages per zspage wasted bytes used% 1 144 96 2 80 99 3 16 99 4 160 99 Current algorithm will select 2 page per zspage configuration, as it's the first one to reach 99%. However, 3 pages per zspage waste less memory. Change algorithm and select zspage configuration that has lowest wasted value. Link: https://lkml.kernel.org/r/20230118005210.2814763-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20230118005210.2814763-2-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Sync mm-stable with mm-hotfixes-stable to pick up dependent patchesAndrew Morton2023-01-311-32/+205
|\ | | | | | | Merge branch 'mm-hotfixes-stable' into mm-stable
| * zsmalloc: fix a race with deferred_handles storingNhat Pham2023-01-311-32/+205
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, there is a race between zs_free() and zs_reclaim_page(): zs_reclaim_page() finds a handle to an allocated object, but before the eviction happens, an independent zs_free() call to the same handle could come in and overwrite the object value stored at the handle with the last deferred handle. When zs_reclaim_page() finally gets to call the eviction handler, it will see an invalid object value (i.e the previous deferred handle instead of the original object value). This race happens quite infrequently. We only managed to produce it with out-of-tree developmental code that triggers zsmalloc writeback with a much higher frequency than usual. This patch fixes this race by storing the deferred handle in the object header instead. We differentiate the deferred handle from the other two cases (handle for allocated object, and linkage for free object) with a new tag. If zspage reclamation succeeds, we will free these deferred handles by walking through the zspage objects. On the other hand, if zspage reclamation fails, we reconstruct the zspage freelist (with the deferred handle tag and allocated tag) before trying again with the reclamation. [arnd@arndb.de: avoid unused-function warning] Link: https://lkml.kernel.org/r/20230117170507.2651972-1-arnd@kernel.org Link: https://lkml.kernel.org/r/20230110231701.326724-1-nphamcs@gmail.com Fixes: 9997bc017549 ("zsmalloc: implement writeback mechanism for zsmalloc") Signed-off-by: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Seth Jennings <sjenning@redhat.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | mm: remove PageMovable exportGreg Kroah-Hartman2023-01-181-3/+0
|/ | | | | | | | | | | | | | | | | The only in-kernel users that need PageMovable() to be exported are z3fold and zsmalloc and they are only using it for dubious debugging functionality. So remove those usages and the export so that no driver code accidentally thinks that they are allowed to use this symbol. Link: https://lkml.kernel.org/r/20230106135900.3763622-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: implement writeback mechanism for zsmallocNhat Pham2022-12-111-11/+183
| | | | | | | | | | | | | | | | | | This commit adds the writeback mechanism for zsmalloc, analogous to the zbud allocator. Zsmalloc will attempt to determine the coldest zspage (i.e least recently used) in the pool, and attempt to write back all the stored compressed objects via the pool's evict handler. Link: https://lkml.kernel.org/r/20221128191616.1261026-7-nphamcs@gmail.com Signed-off-by: Nhat Pham <nphamcs@gmail.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Seth Jennings <sjenning@redhat.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: add zpool_ops field to zs_pool to store evict handlersNhat Pham2022-12-111-1/+10
| | | | | | | | | | | | | | | | This adds a new field to zs_pool to store evict handlers for writeback, analogous to the zbud allocator. Link: https://lkml.kernel.org/r/20221128191616.1261026-6-nphamcs@gmail.com Signed-off-by: Nhat Pham <nphamcs@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Seth Jennings <sjenning@redhat.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: add a LRU to zs_pool to keep track of zspages in LRU orderNhat Pham2022-12-111-0/+50
| | | | | | | | | | | | | | | This helps determines the coldest zspages as candidates for writeback. Link: https://lkml.kernel.org/r/20221128191616.1261026-5-nphamcs@gmail.com Signed-off-by: Nhat Pham <nphamcs@gmail.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Seth Jennings <sjenning@redhat.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: consolidate zs_pool's migrate_lock and size_class's locksNhat Pham2022-12-111-50/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, zsmalloc has a hierarchy of locks, which includes a pool-level migrate_lock, and a lock for each size class. We have to obtain both locks in the hotpath in most cases anyway, except for zs_malloc. This exception will no longer exist when we introduce a LRU into the zs_pool for the new writeback functionality - we will need to obtain a pool-level lock to synchronize LRU handling even in zs_malloc. In preparation for zsmalloc writeback, consolidate these locks into a single pool-level lock, which drastically reduces the complexity of synchronization in zsmalloc. We have also benchmarked the lock consolidation to see the performance effect of this change on zram. First, we ran a synthetic FS workload on a server machine with 36 cores (same machine for all runs), using fs_mark -d ../zram1mnt -s 100000 -n 2500 -t 32 -k before and after for btrfs and ext4 on zram (FS usage is 80%). Here is the result (unit is file/second): With lock consolidation (btrfs): Average: 13520.2, Median: 13531.0, Stddev: 137.5961482019028 Without lock consolidation (btrfs): Average: 13487.2, Median: 13575.0, Stddev: 309.08283679298665 With lock consolidation (ext4): Average: 16824.4, Median: 16839.0, Stddev: 89.97388510006668 Without lock consolidation (ext4) Average: 16958.0, Median: 16986.0, Stddev: 194.7370021336469 As you can see, we observe a 0.3% regression for btrfs, and a 0.9% regression for ext4. This is a small, barely measurable difference in my opinion. For a more realistic scenario, we also tries building the kernel on zram. Here is the time it takes (in seconds): With lock consolidation (btrfs): real Average: 319.6, Median: 320.0, Stddev: 0.8944271909999159 user Average: 6894.2, Median: 6895.0, Stddev: 25.528415540334656 sys Average: 521.4, Median: 522.0, Stddev: 1.51657508881031 Without lock consolidation (btrfs): real Average: 319.8, Median: 320.0, Stddev: 0.8366600265340756 user Average: 6896.6, Median: 6899.0, Stddev: 16.04057355583023 sys Average: 520.6, Median: 521.0, Stddev: 1.140175425099138 With lock consolidation (ext4): real Average: 320.0, Median: 319.0, Stddev: 1.4142135623730951 user Average: 6896.8, Median: 6878.0, Stddev: 28.621670111997307 sys Average: 521.2, Median: 521.0, Stddev: 1.7888543819998317 Without lock consolidation (ext4) real Average: 319.6, Median: 319.0, Stddev: 0.8944271909999159 user Average: 6886.2, Median: 6887.0, Stddev: 16.93221781102523 sys Average: 520.4, Median: 520.0, Stddev: 1.140175425099138 The difference is entirely within the noise of a typical run on zram. This hardly justifies the complexity of maintaining both the pool lock and the class lock. In fact, for writeback, we would need to introduce yet another lock to prevent data races on the pool's LRU, further complicating the lock handling logic. IMHO, it is just better to collapse all of these into a single pool-level lock. Link: https://lkml.kernel.org/r/20221128191616.1261026-4-nphamcs@gmail.com Signed-off-by: Nhat Pham <nphamcs@gmail.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Seth Jennings <sjenning@redhat.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zram: add size class equals check into recompressionAlexey Romanov2022-11-301-0/+21
| | | | | | | | | | | | | | | | | It makes no sense for us to recompress the object if it will be in the same size class. We anyway don't get any memory gain. But, at the same time, we get a CPU time overhead when inserting this object into zspage and decompressing it afterwards. [senozhatsky: rebased and fixed conflicts] Link: https://lkml.kernel.org/r/20221109115047.2921851-9-senozhatsky@chromium.org Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: replace IS_ERR() with IS_ERR_VALUE()Deming Wang2022-11-301-1/+1
| | | | | | | | | Avoid typecasts that are needed for IS_ERR() and use IS_ERR_VALUE() instead. Link: https://lkml.kernel.org/r/20221104023818.1728-1-wangdeming@inspur.com Signed-off-by: Deming Wang <wangdeming@inspur.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: zs_destroy_pool: add size_class NULL checkAlexey Romanov2022-10-201-0/+3
| | | | | | | | | | | | | | | Inside the zs_destroy_pool() function, there can still be NULL size_class pointers: if when the next size_class is allocated, inside zs_create_pool() function, kzalloc will return NULL and handling the error condition, zs_create_pool() will call zs_destroy_pool(). Link: https://lkml.kernel.org/r/20221013112825.61869-1-avromanov@sberdevices.ru Fixes: f24263a5a076 ("zsmalloc: remove unnecessary size_class NULL check") Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: use correct types in _first_obj_offset functionsAlexey Romanov2022-10-031-4/+4
| | | | | | | | | | | | | | | | | Since commit ffedd09fa9b0 ("zsmalloc: Stop using slab fields in struct page") we are using page->page_type (unsigned int) field instead of page->units (int) as first object offset in a subpage of zspage. So get_first_obj_offset() and set_first_obj_offset() functions should work with unsigned int type. Link: https://lkml.kernel.org/r/20220909083722.85024-1-avromanov@sberdevices.ru Fixes: ffedd09fa9b0 ("zsmalloc: Stop using slab fields in struct page") Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: zs_object_copy: replace email link to docAlexey Romanov2022-09-111-2/+2
| | | | | | | | | | | | | Emails are not documentation. [akpm@linux-foundation.org: fix whitespace damage, repair doc reference] [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20220815144825.39001-1-avromanov@sberdevices.ru Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: remove unnecessary size_class NULL checkAlexey Romanov2022-09-111-7/+0
| | | | | | | | | | | | | | | | | | | | pool->size_class array elements can't be NULL, so this check is not needed. In the whole code, we assign pool->size_class[i] values that are not NULL. Releasing memory for these values occurs in the zs_destroy_pool() function, which also releases and destroys the pool. In addition, in the zs_stats_size_show() and async_free_zspage(), with similar iterations over the array, we don't check it for NULL pointer. Link: https://lkml.kernel.org/r/20220811153755.16102-3-avromanov@sberdevices.ru Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: zs_object_copy: add clarifying commentAlexey Romanov2022-09-111-0/+7
| | | | | | | | | | | | | | | | | | | | | | | Patch series "tidy up zsmalloc implementation" This patchset remove some unnecessary checks and adds a clarifying comment. While analysing zs_object_copy() function code, I spent some time to understand what the call kunmap_atomic(d_addr) is for. It seems that this point is not trivial and it is worth adding a comment. This patch (of 2): It's not obvious why kunmap_atomic(d_addr) call is needed. [akpm@linux-foundation.org: tweak comment layout] Link: https://lkml.kernel.org/r/20220811153755.16102-1-avromanov@sberdevices.ru Link: https://lkml.kernel.org/r/20220811153755.16102-2-avromanov@sberdevices.ru Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/zsmalloc: do not attempt to free IS_ERR handleSergey Senozhatsky2022-08-281-1/+1
| | | | | | | | | | | | | | | | | zsmalloc() now returns ERR_PTR values as handles, which zram accidentally can pass to zs_free(). Another bad scenario is when zcomp_compress() fails - handle has default -ENOMEM value, and zs_free() will try to free that "pointer value". Add the missing check and make sure that zs_free() bails out when ERR_PTR() is passed to it. Link: https://lkml.kernel.org/r/20220816050906.2583956-1-senozhatsky@chromium.org Fixes: c7e6f17b52e9 ("zsmalloc: zs_malloc: return ERR_PTR on failure") Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org>, Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'mm-stable-2022-08-03' of ↵Linus Torvalds2022-08-051-6/+10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Most of the MM queue. A few things are still pending. Liam's maple tree rework didn't make it. This has resulted in a few other minor patch series being held over for next time. Multi-gen LRU still isn't merged as we were waiting for mapletree to stabilize. The current plan is to merge MGLRU into -mm soon and to later reintroduce mapletree, with a view to hopefully getting both into 6.1-rc1. Summary: - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe Lin, Yang Shi, Anshuman Khandual and Mike Rapoport - Some kmemleak fixes from Patrick Wang and Waiman Long - DAMON updates from SeongJae Park - memcg debug/visibility work from Roman Gushchin - vmalloc speedup from Uladzislau Rezki - more folio conversion work from Matthew Wilcox - enhancements for coherent device memory mapping from Alex Sierra - addition of shared pages tracking and CoW support for fsdax, from Shiyang Ruan - hugetlb optimizations from Mike Kravetz - Mel Gorman has contributed some pagealloc changes to improve latency and realtime behaviour. - mprotect soft-dirty checking has been improved by Peter Xu - Many other singleton patches all over the place" [ XFS merge from hell as per Darrick Wong in https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ] * tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits) tools/testing/selftests/vm/hmm-tests.c: fix build mm: Kconfig: fix typo mm: memory-failure: convert to pr_fmt() mm: use is_zone_movable_page() helper hugetlbfs: fix inaccurate comment in hugetlbfs_statfs() hugetlbfs: cleanup some comments in inode.c hugetlbfs: remove unneeded header file hugetlbfs: remove unneeded hugetlbfs_ops forward declaration hugetlbfs: use helper macro SZ_1{K,M} mm: cleanup is_highmem() mm/hmm: add a test for cross device private faults selftests: add soft-dirty into run_vmtests.sh selftests: soft-dirty: add test for mprotect mm/mprotect: fix soft-dirty check in can_change_pte_writable() mm: memcontrol: fix potential oom_lock recursion deadlock mm/gup.c: fix formatting in check_and_migrate_movable_page() xfs: fail dax mount if reflink is enabled on a partition mm/memcontrol.c: remove the redundant updating of stats_flush_threshold userfaultfd: don't fail on unrecognized features hugetlb_cgroup: fix wrong hugetlb cgroup numa stat ...
| * zsmalloc: zs_malloc: return ERR_PTR on failureHui Zhu2022-07-291-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | zs_malloc returns 0 if it fails. zs_zpool_malloc will return -1 when zs_malloc return 0. But -1 makes the return value unclear. For example, when zswap_frontswap_store calls zs_malloc through zs_zpool_malloc, it will return -1 to its caller. The other return value is -EINVAL, -ENODEV or something else. This commit changes zs_malloc to return ERR_PTR on failure. It didn't just let zs_zpool_malloc return -ENOMEM becaue zs_malloc has two types of failure: - size is not OK return -EINVAL - memory alloc fail return -ENOMEM. Link: https://lkml.kernel.org/r/20220714080757.12161-1-teawater@gmail.com Signed-off-by: Hui Zhu <teawater@antgroup.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * mm: shrinkers: provide shrinkers with namesRoman Gushchin2022-07-031-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently shrinkers are anonymous objects. For debugging purposes they can be identified by count/scan function names, but it's not always useful: e.g. for superblock's shrinkers it's nice to have at least an idea of to which superblock the shrinker belongs. This commit adds names to shrinkers. register_shrinker() and prealloc_shrinker() functions are extended to take a format and arguments to master a name. In some cases it's not possible to determine a good name at the time when a shrinker is allocated. For such cases shrinker_debugfs_rename() is provided. The expected format is: <subsystem>-<shrinker_type>[:<instance>]-<id> For some shrinkers an instance can be encoded as (MAJOR:MINOR) pair. After this change the shrinker debugfs directory looks like: $ cd /sys/kernel/debug/shrinker/ $ ls dquota-cache-16 sb-devpts-28 sb-proc-47 sb-tmpfs-42 mm-shadow-18 sb-devtmpfs-5 sb-proc-48 sb-tmpfs-43 mm-zspool:zram0-34 sb-hugetlbfs-17 sb-pstore-31 sb-tmpfs-44 rcu-kfree-0 sb-hugetlbfs-33 sb-rootfs-2 sb-tmpfs-49 sb-aio-20 sb-iomem-12 sb-securityfs-6 sb-tracefs-13 sb-anon_inodefs-15 sb-mqueue-21 sb-selinuxfs-22 sb-xfs:vda1-36 sb-bdev-3 sb-nsfs-4 sb-sockfs-8 sb-zsmalloc-19 sb-bpf-32 sb-pipefs-14 sb-sysfs-26 thp-deferred_split-10 sb-btrfs:vda2-24 sb-proc-25 sb-tmpfs-1 thp-zero-9 sb-cgroup2-30 sb-proc-39 sb-tmpfs-27 xfs-buf:vda1-37 sb-configfs-23 sb-proc-41 sb-tmpfs-29 xfs-inodegc:vda1-38 sb-dax-11 sb-proc-45 sb-tmpfs-35 sb-debugfs-7 sb-proc-46 sb-tmpfs-40 [roman.gushchin@linux.dev: fix build warnings] Link: https://lkml.kernel.org/r/Yr+ZTnLb9lJk6fJO@castle Reported-by: kernel test robot <lkp@intel.com> Link: https://lkml.kernel.org/r/20220601032227.4076670-4-roman.gushchin@linux.dev Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Dave Chinner <dchinner@redhat.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | mm: Convert all PageMovable users to movable_operationsMatthew Wilcox (Oracle)2022-08-021-80/+22
|/ | | | | | | | | These drivers are rather uncomfortably hammered into the address_space_operations hole. They aren't filesystems and don't behave like filesystems. They just need their own movable_operations structure, which we can point to directly from page->mapping. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
* zsmalloc: fix races between asynchronous zspage free and page migrationSultan Alsawaf2022-05-131-4/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The asynchronous zspage free worker tries to lock a zspage's entire page list without defending against page migration. Since pages which haven't yet been locked can concurrently migrate off the zspage page list while lock_zspage() churns away, lock_zspage() can suffer from a few different lethal races. It can lock a page which no longer belongs to the zspage and unsafely dereference page_private(), it can unsafely dereference a torn pointer to the next page (since there's a data race), and it can observe a spurious NULL pointer to the next page and thus not lock all of the zspage's pages (since a single page migration will reconstruct the entire page list, and create_page_chain() unconditionally zeroes out each list pointer in the process). Fix the races by using migrate_read_lock() in lock_zspage() to synchronize with page migration. Link: https://lkml.kernel.org/r/20220509024703.243847-1-sultan@kerneltoast.com Fixes: 77ff465799c602 ("zsmalloc: zs_page_migrate: skip unnecessary loops but not return -EBUSY if zspage is not inuse") Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zsmalloc: replace get_cpu_var with local_lockMike Galbraith2022-01-221-3/+8
| | | | | | | | | | | | | | | | | | | | | | | The usage of get_cpu_var() in zs_map_object() is problematic because it disables preemption and makes it impossible to acquire any sleeping lock on PREEMPT_RT such as a spinlock_t. Replace the get_cpu_var() usage with a local_lock_t which is embedded struct mapping_area. It ensures that the access the struct is synchronized against all users on the same CPU. [minchan: remove the bit_spin_lock part and change the title] Link: https://lkml.kernel.org/r/20211115185909.3949505-10-minchan@kernel.org Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Minchan Kim <minchan@kernel.org> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: replace per zpage lock with pool->migrate_lockMinchan Kim2022-01-221-109/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The zsmalloc has used a bit for spin_lock in zpage handle to keep zpage object alive during several operations. However, it causes the problem for PREEMPT_RT as well as introducing too complicated. This patch replaces the bit spin_lock with pool->migrate_lock rwlock. It could make the code simple as well as zsmalloc work under PREEMPT_RT. The drawback is the pool->migrate_lock is bigger granuarity than per zpage lock so the contention would be higher than old when both IO-related operations(i.e., zsmalloc, zsfree, zs_[map|unmap]) and compaction(page/zpage migration) are going in parallel(*, the migrate_lock is rwlock and IO related functions are all read side lock so there is no contention). However, the write-side is fast enough(dominant overhead is just page copy) so it wouldn't affect much. If the lock granurity becomes more problem later, we could introduce table locks based on handle as a hash value. Link: https://lkml.kernel.org/r/20211115185909.3949505-9-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: remove zspage isolation for migrationMinchan Kim2022-01-221-149/+8
| | | | | | | | | | | | | | | | | | | | | | | zspage isolation for migration introduced additional exceptions to be dealt with since the zspage was isolated from class list. The reason why I isolated zspage from class list was to prevent race between obj_malloc and page migration via allocating zpage from the zspage further. However, it couldn't prevent object freeing from zspage so it needed corner case handling. This patch removes the whole mess. Now, we are fine since class->lock and zspage->lock can prevent the race. Link: https://lkml.kernel.org/r/20211115185909.3949505-7-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: move huge compressed obj from page to zspageMinchan Kim2022-01-221-24/+26
| | | | | | | | | | | | | | | The flag aims for zspage, not per page. Let's move it to zspage. Link: https://lkml.kernel.org/r/20211115185909.3949505-6-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: introduce obj_allocatedMinchan Kim2022-01-221-17/+16
| | | | | | | | | | | | | | | | The usage pattern for obj_to_head is to check whether the zpage is allocated or not. Thus, introduce obj_allocated. Link: https://lkml.kernel.org/r/20211115185909.3949505-5-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: decouple class actions from zspage worksMinchan Kim2022-01-221-10/+13
| | | | | | | | | | | | | | | | | This patch moves class stat update out of obj_malloc since it's not related to zspage operation. This is a preparation to introduce new lock scheme in next patch. Link: https://lkml.kernel.org/r/20211115185909.3949505-4-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: rename zs_stat_type to class_stat_typeMinchan Kim2022-01-221-12/+12
| | | | | | | | | | | | | | | The stat aims for class stat, not zspage so rename it. Link: https://lkml.kernel.org/r/20211115185909.3949505-3-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: introduce some helper functionsMinchan Kim2022-01-221-31/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "zsmalloc: remove bit_spin_lock", v2. zsmalloc uses bit_spin_lock to minimize space overhead since it's zpage granularity lock. However, it causes zsmalloc non-working under PREEMPT_RT as well as adding too much complication. This patchset tries to replace the bit_spin_lock with per-pool rwlock. It also removes unnecessary zspage isolation logic from class, which was the other part too much complication added into zsmalloc. Last patch changes the get_cpu_var to local_lock to make it work in PREEMPT_RT. This patch (of 9): get_zspage_mapping returns fullness as well as class_idx. However, the fullness is usually not used since it could be stale in some contexts. It causes misleading as well as unnecessary instructions so this patch introduces zspage_class. obj_to_location also produces page and index but we don't need always the index, either so this patch introduces obj_to_page. Link: https://lkml.kernel.org/r/20211115185909.3949505-1-minchan@kernel.org Link: https://lkml.kernel.org/r/20211115185909.3949505-2-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: Stop using slab fields in struct pageMatthew Wilcox (Oracle)2022-01-061-9/+9
| | | | | | | | | | | | | | | | The ->freelist and ->units members of struct page are for the use of slab only. I'm not particularly familiar with zsmalloc, so generate the same code by using page->index to store 'page' (page->index and page->freelist are at the same offset in struct page). This should be cleaned up properly at some point by somebody who is familiar with zsmalloc. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
* mm/zsmalloc.c: close race window between zs_pool_dec_isolated() and ↵Miaohe Lin2021-11-061-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | zs_unregister_migration() There is one possible race window between zs_pool_dec_isolated() and zs_unregister_migration() because wait_for_isolated_drain() checks the isolated count without holding class->lock and there is no order inside zs_pool_dec_isolated(). Thus the below race window could be possible: zs_pool_dec_isolated zs_unregister_migration check pool->destroying != 0 pool->destroying = true; smp_mb(); wait_for_isolated_drain() wait for pool->isolated_pages == 0 atomic_long_dec(&pool->isolated_pages); atomic_long_read(&pool->isolated_pages) == 0 Since we observe the pool->destroying (false) before atomic_long_dec() for pool->isolated_pages, waking pool->migration_wait up is missed. Fix this by ensure checking pool->destroying happens after the atomic_long_dec(&pool->isolated_pages). Link: https://lkml.kernel.org/r/20210708115027.7557-1-linmiaohe@huawei.com Fixes: 701d678599d0 ("mm/zsmalloc.c: fix race condition in zs_destroy_pool") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Henry Burns <henryburns@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc.c: improve readability for async_free_zspage()Miaohe Lin2021-07-011-1/+1
| | | | | | | | | | | | | | The class is extracted from pool->size_class[class_idx] again before calling __free_zspage(). It looks like class will change after we fetch the class lock. But this is misleading as class will stay unchanged. Link: https://lkml.kernel.org/r/20210624123930.1769093-4-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc.c: remove confusing code in obj_free()Miaohe Lin2021-07-011-1/+0
| | | | | | | | | | | | | | | | | | | | | | | Patch series "Cleanup for zsmalloc". This series contains cleanups to remove confusing code in obj_free(), combine two atomic ops and improve readability for async_free_zspage(). More details can be found in the respective changelogs. This patch (of 2): OBJ_ALLOCATED_TAG is only set for handle to indicate allocated object. It's irrelevant with obj. So remove this misleading code to improve readability. Link: https://lkml.kernel.org/r/20210624123930.1769093-1-linmiaohe@huawei.com Link: https://lkml.kernel.org/r/20210624123930.1769093-2-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fix typos in commentsIngo Molnar2021-05-071-1/+1
| | | | | | | | | | | | | | Fix ~94 single-word typos in locking code comments, plus a few very obvious grammar mistakes. Link: https://lkml.kernel.org/r/20210322212624.GA1963421@gmail.com Link: https://lore.kernel.org/r/20210322205203.GB1959563@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Cc: Bhaskar Chowdhury <unixbhaskar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fix some typos and code style problemsShijie Luo2021-05-071-2/+2
| | | | | | | | | | | | | | | | | | fix some typos and code style problems in mm. gfp.h: s/MAXNODES/MAX_NUMNODES mmzone.h: s/then/than rmap.c: s/__vma_split()/__vma_adjust() swap.c: s/__mod_zone_page_stat/__mod_zone_page_state, s/is is/is swap_state.c: s/whoes/whose z3fold.c: code style problem fix in z3fold_unregister_migration zsmalloc.c: s/of/or, s/give/given Link: https://lkml.kernel.org/r/20210419083057.64820-1-luoshijie1@huawei.com Signed-off-by: Shijie Luo <luoshijie1@huawei.com> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc: use BUG_ON instead of if condition followed by BUG.zhouchuangao2021-05-051-4/+2
| | | | | | | | | | | It can be optimized at compile time. Link: https://lkml.kernel.org/r/1616727798-9110-1-git-send-email-zhouchuangao@vivo.com Signed-off-by: zhouchuangao <zhouchuangao@vivo.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc.c: use page_private() to access page->privateMiaohe Lin2021-02-261-1/+1
| | | | | | | | | | | | It's recommended to use helper macro page_private() to access the private field of page. Use such helper to eliminate direct access. Link: https://lkml.kernel.org/r/20210203091857.20017-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: account the number of compacted pages correctlyRokudo Yan2021-02-261-6/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | There exists multiple path may do zram compaction concurrently. 1. auto-compaction triggered during memory reclaim 2. userspace utils write zram<id>/compaction node So, multiple threads may call zs_shrinker_scan/zs_compact concurrently. But pages_compacted is a per zsmalloc pool variable and modification of the variable is not serialized(through under class->lock). There are two issues here: 1. the pages_compacted may not equal to total number of pages freed(due to concurrently add). 2. zs_shrinker_scan may not return the correct number of pages freed(issued by current shrinker). The fix is simple: 1. account the number of pages freed in zs_compact locally. 2. use actomic variable pages_compacted to accumulate total number. Link: https://lkml.kernel.org/r/20210202122235.26885-1-wu-yan@tcl.com Fixes: 860c707dca155a56 ("zsmalloc: account the number of compacted pages") Signed-off-by: Rokudo Yan <wu-yan@tcl.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc.c: convert to use kmem_cache_zalloc in cache_alloc_zspage()Miaohe Lin2021-02-261-2/+1
| | | | | | | | | | | | | We always memset the zspage allocated via cache_alloc_zspage. So it's more convenient to use kmem_cache_zalloc in cache_alloc_zspage than caller do it manually. Link: https://lkml.kernel.org/r/20210114120032.25885-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc.c: rework the list_add code in insert_zspage()Miaohe Lin2020-12-151-7/+4
| | | | | | | | | | | Rework the list_add code to make it more readable and simple. Link: https://lkml.kernel.org/r/20201015130107.65195-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc.c: drop ZSMALLOC_PGTABLE_MAPPINGMinchan Kim2020-12-061-54/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While I was doing zram testing, I found sometimes decompression failed since the compression buffer was corrupted. With investigation, I found below commit calls cond_resched unconditionally so it could make a problem in atomic context if the task is reschedule. BUG: sleeping function called from invalid context at mm/vmalloc.c:108 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 946, name: memhog 3 locks held by memhog/946: #0: ffff9d01d4b193e8 (&mm->mmap_lock#2){++++}-{4:4}, at: __mm_populate+0x103/0x160 #1: ffffffffa3d53de0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0xa98/0x1160 #2: ffff9d01d56b8110 (&zspage->lock){.+.+}-{3:3}, at: zs_map_object+0x8e/0x1f0 CPU: 0 PID: 946 Comm: memhog Not tainted 5.9.3-00011-gc5bfc0287345-dirty #316 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014 Call Trace: unmap_kernel_range_noflush+0x2eb/0x350 unmap_kernel_range+0x14/0x30 zs_unmap_object+0xd5/0xe0 zram_bvec_rw.isra.0+0x38c/0x8e0 zram_rw_page+0x90/0x101 bdev_write_page+0x92/0xe0 __swap_writepage+0x94/0x4a0 pageout+0xe3/0x3a0 shrink_page_list+0xb94/0xd60 shrink_inactive_list+0x158/0x460 We can fix this by removing the ZSMALLOC_PGTABLE_MAPPING feature (which contains the offending calling code) from zsmalloc. Even though this option showed some amount improvement(e.g., 30%) in some arm32 platforms, it has been headache to maintain since it have abused APIs[1](e.g., unmap_kernel_range in atomic context). Since we are approaching to deprecate 32bit machines and already made the config option available for only builtin build since v5.8, lastly it has been not default option in zsmalloc, it's time to drop the option for better maintenance. [1] http://lore.kernel.org/linux-mm/20201105170249.387069-1-minchan@kernel.org Fixes: e47110e90584 ("mm/vunmap: add cond_resched() in vunmap_pmd_range") Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Harish Sriram <harish@linux.ibm.com> Cc: Uladzislau Rezki <urezki@gmail.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201117202916.GA3856507@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zsmalloc: switch from alloc_vm_area to get_vm_areaChristoph Hellwig2020-10-181-2/+8
| | | | | | | | | | | | | | | | | | | | | | | Just manually pre-fault the PTEs using apply_to_page_range. Co-developed-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Juergen Gross <jgross@suse.com> Cc: Matthew Auld <matthew.auld@intel.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Link: https://lkml.kernel.org/r/20201002122204.1534411-6-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/zsmalloc.c: fix duplicated wordsRandy Dunlap2020-08-121-1/+1
| | | | | | | | | | | Change "as as" to "as a". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/20200801173822.14973-16-rdunlap@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: reorder includes after introduction of linux/pgtable.hMike Rapoport2020-06-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include of the latter in the middle of asm includes. Fix this up with the aid of the below script and manual adjustments here and there. import sys import re if len(sys.argv) is not 3: print "USAGE: %s <file> <header>" % (sys.argv[0]) sys.exit(1) hdr_to_move="#include <linux/%s>" % sys.argv[2] moved = False in_hdrs = False with open(sys.argv[1], "r") as f: lines = f.readlines() for _line in lines: line = _line.rstrip(' ') if line == hdr_to_move: continue if line.startswith("#include <linux/"): in_hdrs = True elif not moved and in_hdrs: moved = True print hdr_to_move print line Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: introduce include/linux/pgtable.hMike Rapoport2020-06-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The include/linux/pgtable.h is going to be the home of generic page table manipulation functions. Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and make the latter include asm/pgtable.h. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: remove map_vm_rangeChristoph Hellwig2020-06-021-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switch all callers to map_kernel_range, which symmetric to the unmap side (as well as the _noflush versions). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Gao Xiang <xiang@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Kelley <mikelley@microsoft.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200414131348.444715-17-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: rename CONFIG_PGTABLE_MAPPING to CONFIG_ZSMALLOC_PGTABLE_MAPPINGChristoph Hellwig2020-06-021-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename the Kconfig variable to clarify the scope. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Gao Xiang <xiang@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Kelley <mikelley@microsoft.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200414131348.444715-11-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use fallthrough;Joe Perches2020-04-071-1/+1
| | | | | | | | | | | | | | Convert the various /* fallthrough */ comments to the pseudo-keyword fallthrough; Done via script: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/ Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: http://lkml.kernel.org/r/f62fea5d10eb0ccfc05d87c242a620c261219b66.camel@perches.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>