The patch titled Subject: mm: memcg/slab: remove memcg_kmem_get_cache() has been added to the -mm tree. Its filename is mm-memcg-slab-remove-memcg_kmem_get_cache.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-memcg-slab-remove-memcg_kmem_get_cache.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-memcg-slab-remove-memcg_kmem_get_cache.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Roman Gushchin <guro@xxxxxx> Subject: mm: memcg/slab: remove memcg_kmem_get_cache() The memcg_kmem_get_cache() function became really trivial, so let's just inline it into the single call point: memcg_slab_pre_alloc_hook(). It will make the code less bulky and can also help the compiler to generate a better code. Link: http://lkml.kernel.org/r/20200608230654.828134-15-guro@xxxxxx Signed-off-by: Roman Gushchin <guro@xxxxxx> Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Cc: Tobin C. Harding <tobin@xxxxxxxxxx> Cc: Waiman Long <longman@xxxxxxxxxx> Cc: Dennis Zhou <dennis@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/memcontrol.h | 2 -- mm/memcontrol.c | 25 +------------------------ mm/slab.h | 11 +++++++++-- mm/slab_common.c | 2 +- 4 files changed, 11 insertions(+), 29 deletions(-) --- a/include/linux/memcontrol.h~mm-memcg-slab-remove-memcg_kmem_get_cache +++ a/include/linux/memcontrol.h @@ -1403,8 +1403,6 @@ static inline void memcg_set_shrinker_bi } #endif -struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep); - #ifdef CONFIG_MEMCG_KMEM int __memcg_kmem_charge(struct mem_cgroup *memcg, gfp_t gfp, unsigned int nr_pages); --- a/mm/memcontrol.c~mm-memcg-slab-remove-memcg_kmem_get_cache +++ a/mm/memcontrol.c @@ -393,7 +393,7 @@ void memcg_put_cache_ids(void) /* * A lot of the calls to the cache allocation functions are expected to be - * inlined by the compiler. Since the calls to memcg_kmem_get_cache are + * inlined by the compiler. Since the calls to memcg_slab_pre_alloc_hook() are * conditional to this static branch, we'll have to allow modules that does * kmem_cache_alloc and the such to see this symbol as well */ @@ -2901,29 +2901,6 @@ static void memcg_free_cache_id(int id) } /** - * memcg_kmem_get_cache: select memcg or root cache for allocation - * @cachep: the original global kmem cache - * - * Return the kmem_cache we're supposed to use for a slab allocation. - * - * If the cache does not exist yet, if we are the first user of it, we - * create it asynchronously in a workqueue and let the current allocation - * go through with the original cache. - */ -struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep) -{ - struct kmem_cache *memcg_cachep; - - memcg_cachep = READ_ONCE(cachep->memcg_params.memcg_cache); - if (unlikely(!memcg_cachep)) { - queue_work(system_wq, &cachep->memcg_params.work); - return cachep; - } - - return memcg_cachep; -} - -/** * __memcg_kmem_charge: charge a number of kernel pages to a memcg * @memcg: memory cgroup to charge * @gfp: reclaim mode --- a/mm/slab_common.c~mm-memcg-slab-remove-memcg_kmem_get_cache +++ a/mm/slab_common.c @@ -568,7 +568,7 @@ void memcg_create_kmem_cache(struct kmem } /* - * Since readers won't lock (see memcg_kmem_get_cache()), we need a + * Since readers won't lock (see memcg_slab_pre_alloc_hook()), we need a * barrier here to ensure nobody will see the kmem_cache partially * initialized. */ --- a/mm/slab.h~mm-memcg-slab-remove-memcg_kmem_get_cache +++ a/mm/slab.h @@ -333,9 +333,16 @@ static inline struct kmem_cache *memcg_s if (memcg_kmem_bypass()) return s; - cachep = memcg_kmem_get_cache(s); - if (is_root_cache(cachep)) + cachep = READ_ONCE(s->memcg_params.memcg_cache); + if (unlikely(!cachep)) { + /* + * If memcg cache does not exist yet, we schedule it's + * asynchronous creation and let the current allocation + * go through with the root cache. + */ + queue_work(system_wq, &s->memcg_params.work); return s; + } objcg = get_obj_cgroup_from_current(); if (!objcg) _ Patches currently in -mm which might be from guro@xxxxxx are mm-memcg-factor-out-memcg-and-lruvec-level-changes-out-of-__mod_lruvec_state.patch mm-memcg-prepare-for-byte-sized-vmstat-items.patch mm-memcg-convert-vmstat-slab-counters-to-bytes.patch mm-slub-implement-slub-version-of-obj_to_index.patch mm-memcg-slab-obj_cgroup-api.patch mm-memcg-slab-allocate-obj_cgroups-for-non-root-slab-pages.patch mm-memcg-slab-save-obj_cgroup-for-non-root-slab-objects.patch mm-memcg-slab-charge-individual-slab-objects-instead-of-pages.patch mm-memcg-slab-deprecate-memorykmemslabinfo.patch mm-memcg-slab-move-memcg_kmem_bypass-to-memcontrolh.patch mm-memcg-slab-use-a-single-set-of-kmem_caches-for-all-accounted-allocations.patch mm-memcg-slab-simplify-memcg-cache-creation.patch mm-memcg-slab-remove-memcg_kmem_get_cache.patch mm-memcg-slab-deprecate-slab_root_caches.patch mm-memcg-slab-remove-redundant-check-in-memcg_accumulate_slabinfo.patch mm-memcg-slab-use-a-single-set-of-kmem_caches-for-all-allocations.patch kselftests-cgroup-add-kernel-memory-accounting-tests.patch tools-cgroup-add-memcg_slabinfopy-tool.patch percpu-return-number-of-released-bytes-from-pcpu_free_area.patch mm-memcg-percpu-account-percpu-memory-to-memory-cgroups.patch mm-memcg-percpu-per-memcg-percpu-memory-statistics.patch mm-memcg-charge-memcg-percpu-memory-to-the-parent-cgroup.patch kselftests-cgroup-add-perpcu-memory-accounting-test.patch