kernel/include/linux/slub_def.h, branch linux-6.16.y

mm/slab: move the rest of slub_def.h to mm/slab.h

2023-12-06T10:57:21Z

mm/slab.h is the only place to include include/linux/slub_def.h which has allowed switching between SLAB and SLUB. Now we can simply move the contents over and remove slub_def.h. Use this opportunity to fix up some whitespace (alignment) issues. Reviewed-by: Kees Cook Acked-by: David Rientjes Tested-by: David Rientjes Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka

mm/slab: move struct kmem_cache_cpu declaration to slub.c

2023-12-06T10:57:21Z

Nothing outside SLUB itself accesses the struct kmem_cache_cpu fields so it does not need to be declared in slub_def.h. This allows also to move enum stat_item. Reviewed-by: Kees Cook Acked-by: David Rientjes Tested-by: David Rientjes Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka

slub: Replace cmpxchg_double()

2023-06-05T07:36:39Z

Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Arnd Bergmann Reviewed-by: Mark Rutland Acked-by: Vlastimil Babka Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Tested-by: Mark Rutland Link: https://lore.kernel.org/r/20230531132323.924677086@infradead.org

mm/kasan: simplify and refine kasan_cache code

2023-01-19T01:12:55Z

struct 'kasan_cache' has a member 'is_kmalloc' indicating whether its host kmem_cache is a kmalloc cache. With newly introduced is_kmalloc_cache() helper, 'is_kmalloc' and its related function can be replaced and removed. Also 'kasan_cache' is only needed by KASAN generic mode, and not by SW/HW tag modes, so refine its protection macro accordingly, suggested by Andrey Konoval. Link: https://lkml.kernel.org/r/20230104060605.930910-2-feng.tang@intel.com Signed-off-by: Feng Tang Reviewed-by: Andrey Konovalov Acked-by: Vlastimil Babka Acked-by: David Rientjes Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Christoph Lameter Cc: Dmitry Vyukov Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Joonsoo Kim Cc: Pekka Enberg Cc: Roman Gushchin Cc: Vincenzo Frascino Signed-off-by: Andrew Morton

mm, slub: remove percpu slabs with CONFIG_SLUB_TINY

2022-11-30T23:09:09Z

SLUB gets most of its scalability by percpu slabs. However for CONFIG_SLUB_TINY the goal is minimal memory overhead, not scalability. Thus, #ifdef out the whole kmem_cache_cpu percpu structure and associated code. Additionally to the slab page savings, this reduces percpu allocator usage, and code size. This change builds on recent commit c7323a5ad078 ("mm/slub: restrict sysfs validation to debug caches and make it safe"), as caches with enabled debugging also avoid percpu slabs and all allocations and freeing ends up working with the partial list. With a bit more refactoring by the preceding patches, use the same code paths with CONFIG_SLUB_TINY. Signed-off-by: Vlastimil Babka Acked-by: Mike Rapoport Reviewed-by: Christoph Lameter

mm, slub: disable SYSFS support with CONFIG_SLUB_TINY

2022-11-27T22:38:09Z

Currently SLUB enables its sysfs support depending unconditionally on the general CONFIG_SYSFS setting. To reduce the configuration combination space, make CONFIG_SLUB_TINY disable SLUB's sysfs support by reusing the existing SLAB_SUPPORTS_SYSFS define. It is unlikely that real tiny systems would combine CONFIG_SLUB_TINY with CONFIG_SYSFS, but a randconfig might. Signed-off-by: Vlastimil Babka Acked-by: Mike Rapoport Reviewed-by: Christoph Lameter

mm, slab: ignore hardened usercopy parameters when disabled

2022-11-27T22:35:04Z

With CONFIG_HARDENED_USERCOPY not enabled, there are no __check_heap_object() checks happening that would use the struct kmem_cache useroffset and usersize fields. Yet the fields are still initialized, preventing merging of otherwise compatible caches. Also the fields contribute to struct kmem_cache size unnecessarily when unused. Thus #ifdef them out completely when CONFIG_HARDENED_USERCOPY is disabled. In kmem_dump_obj() print object_size instead of usersize, as that's actually the intention. In a quick virtme boot test, this has reduced the number of caches in /proc/slabinfo from 131 to 111. Cc: Kees Cook Signed-off-by: Vlastimil Babka Acked-by: Roman Gushchin Acked-by: Mike Rapoport Reviewed-by: Christoph Lameter

mm/slub: remove unused kmem_cache_order_objects max

2022-05-02T08:48:40Z

max field holds the largest slab order that was ever used for a slab cache. But it's unused now. Remove it. Signed-off-by: Miaohe Lin Reviewed-by: Muchun Song Acked-by: David Rientjes Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/20220429090545.33413-1-linmiaohe@huawei.com

mm: Convert struct page to struct slab in functions used by other subsystems

2022-01-06T11:26:13Z

KASAN, KFENCE and memcg interact with SLAB or SLUB internals through functions nearest_obj(), obj_to_index() and objs_per_slab() that use struct page as parameter. This patch converts it to struct slab including all callers, through a coccinelle semantic patch. // Options: --include-headers --no-includes --smpl-spacing include/linux/slab_def.h include/linux/slub_def.h mm/slab.h mm/kasan/*.c mm/kfence/kfence_test.c mm/memcontrol.c mm/slab.c mm/slub.c // Note: needs coccinelle 1.1.1 to avoid breaking whitespace @@ @@ -objs_per_slab_page( +objs_per_slab( ... ) { ... } @@ @@ -objs_per_slab_page( +objs_per_slab( ... ) @@ identifier fn =~ "obj_to_index|objs_per_slab"; @@ fn(..., - const struct page *page + const struct slab *slab ,...) { <... ( - page_address(page) + slab_address(slab) | - page + slab ) ...> } @@ identifier fn =~ "nearest_obj"; @@ fn(..., - struct page *page + const struct slab *slab ,...) { <... ( - page_address(page) + slab_address(slab) | - page + slab ) ...> } @@ identifier fn =~ "nearest_obj|obj_to_index|objs_per_slab"; expression E; @@ fn(..., ( - slab_page(E) + E | - virt_to_page(E) + virt_to_slab(E) | - virt_to_head_page(E) + virt_to_slab(E) | - page + page_slab(page) ) ,...) Signed-off-by: Vlastimil Babka Reviewed-by: Andrey Konovalov Reviewed-by: Roman Gushchin Acked-by: Johannes Weiner Cc: Julia Lawall Cc: Luis Chamberlain Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Marco Elver Cc: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Cc: Cc:

mm/slub: Finish struct page to struct slab conversion

2022-01-06T11:26:02Z

Update comments mentioning pages to mention slabs where appropriate. Also some goto labels. Signed-off-by: Vlastimil Babka Reviewed-by: Roman Gushchin