kernel/linux.git/mm/slub.c, branch v5.18

mm, kfence: support kmem_dump_obj() for KFENCE objects

2022-04-15T21:49:55+00:00

Calling kmem_obj_info() via kmem_dump_obj() on KFENCE objects has been producing garbage data due to the object not actually being maintained by SLAB or SLUB. Fix this by implementing __kfence_obj_info() that copies relevant information to struct kmem_obj_info when the object was allocated by KFENCE; this is called by a common kmem_obj_info(), which also calls the slab/slub/slob specific variant now called __kmem_obj_info(). For completeness, kmem_dump_obj() now displays if the object was allocated by KFENCE. Link: https://lore.kernel.org/all/20220323090520.GG16885@xsang-OptiPlex-9020/ Link: https://lkml.kernel.org/r/20220406131558.3558585-1-elver@google.com Fixes: b89fb5ef0ce6 ("mm, kfence: insert KFENCE hooks for SLUB") Fixes: d3fb45f370d9 ("mm, kfence: insert KFENCE hooks for SLAB") Signed-off-by: Marco Elver Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reported-by: kernel test robot Acked-by: Vlastimil Babka [slab] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'slab-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

2022-03-23T19:33:21+00:00

Pull slab updates from Vlastimil Babka: - A few non-trivial SLUB code cleanups, most notably a refactoring of deactivate_slab(). - A bunch of trivial changes, such as removal of unused parameters, making stuff static, and employing helper functions. * tag 'slab-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: mm: slub: Delete useless parameter of alloc_slab_page() mm: slab: Delete unused SLAB_DEACTIVATED flag mm/slub: remove forced_order parameter in calculate_sizes mm/slub: refactor deactivate_slab() mm/slub: limit number of node partial slabs only in cache creation mm/slub: use helper macro __ATTR_XX_MODE for SLAB_ATTR(_RO) mm/slab_common: use helper function is_power_of_2() mm/slob: make kmem_cache_boot static

mm: introduce kmem_cache_alloc_lru

2022-03-22T22:57:03+00:00

We currently allocate scope for every memcg to be able to tracked on every superblock instantiated in the system, regardless of whether that superblock is even accessible to that memcg. These huge memcg counts come from container hosts where memcgs are confined to just a small subset of the total number of superblocks that instantiated at any given point in time. For these systems with huge container counts, list_lru does not need the capability of tracking every memcg on every superblock. What it comes down to is that adding the memcg to the list_lru at the first insert. So introduce kmem_cache_alloc_lru to allocate objects and its list_lru. In the later patch, we will convert all inode and dentry allocation from kmem_cache_alloc to kmem_cache_alloc_lru. Link: https://lkml.kernel.org/r/20220228122126.37293-3-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Roman Gushchin Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'slab/for-5.18/cleanups' into slab/for-linus

2022-03-21T18:48:49+00:00

Non-trivial SLUB code cleanups, notably refactoring of deactivate_slab().

mm: slub: Delete useless parameter of alloc_slab_page()

2022-03-10T17:14:25+00:00

The parameter @s is useless for alloc_slab_page(). It was added in 2014 by commit 5dfb41750992 ("sl[au]b: charge slabs to kmemcg explicitly"). The need for it was removed in 2020 by commit 1f3147b49d75 ("mm: slub: call account_slab_page() after slab page initialization"). Let's delete it. [willy@infradead.org: Added detailed history of @s] Signed-off-by: Xiongwei Song Reviewed-by: Matthew Wilcox (Oracle) Acked-by: David Rientjes Reviewed-by: Roman Gushchin Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/20220310140701.87908-3-sxwjean@me.com

mm/slub: remove forced_order parameter in calculate_sizes

2022-03-09T11:28:08+00:00

Since commit 32a6f409b693 ("mm, slub: remove runtime allocation order changes"), forced_order is always -1. Remove this unneeded parameter to simplify the code. Signed-off-by: Miaohe Lin Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/20220309092036.50844-1-linmiaohe@huawei.com

mm/slub: refactor deactivate_slab()

2022-03-09T11:25:29+00:00

Simplify deactivate_slab() by unlocking n->list_lock and retrying cmpxchg_double() when cmpxchg_double() fails, and perform add_{partial,full} only when it succeed. Releasing and taking n->list_lock again here is not harmful as SLUB avoids deactivating slabs as much as possible. [ vbabka@suse.cz: perform add_{partial,full} when cmpxchg_double() succeed. count deactivating full slabs even if debugging flag is not set. ] Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Vlastimil Babka Reviewed-by: Roman Gushchin Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/20220307074057.902222-3-42.hyeyoo@gmail.com

mm/slub: limit number of node partial slabs only in cache creation

2022-03-09T11:25:18+00:00

SLUB sets number of minimum partial slabs for node (min_partial) using set_min_partial(). SLUB holds at least min_partial slabs even if they're empty to avoid excessive use of page allocator. set_min_partial() limits value of min_partial limits value of min_partial MIN_PARTIAL and MAX_PARTIAL. As set_min_partial() can be called by min_partial_store() too, Only limit value of min_partial in kmem_cache_open() so that it can be changed to value that a user wants. [ rientjes@google.com: Fold set_min_partial() into its callers ] Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Vlastimil Babka Reviewed-by: Roman Gushchin Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/20220307074057.902222-2-42.hyeyoo@gmail.com

mm/slub: use helper macro __ATTR_XX_MODE for SLAB_ATTR(_RO)

2022-03-07T17:08:35+00:00

This allows more concise code, and VERIFY_OCTAL_PERMISSIONS() can help validate any future change. Signed-off-by: Lianjie Zhang Acked-by: David Rientjes Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/20220306073818.15089-1-zhanglianjie@uniontech.com

mm/slub: Define struct slab fields for CONFIG_SLUB_CPU_PARTIAL only when enabled

2022-01-06T11:26:53+00:00

The fields 'next' and 'slabs' are only used when CONFIG_SLUB_CPU_PARTIAL is enabled. We can put their definition to #ifdef to prevent accidental use when disabled. Currenlty show_slab_objects() and slabs_cpu_partial_show() contain code accessing the slabs field that's effectively dead with CONFIG_SLUB_CPU_PARTIAL=n through the wrappers slub_percpu_partial() and slub_percpu_partial_read_once(), but to prevent a compile error, we need to hide all this code behind #ifdef. Signed-off-by: Vlastimil Babka Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Roman Gushchin Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>