diff options
| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2025-03-14 13:36:13 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-03-21 22:03:12 -0700 |
| commit | 7cc57ecae40a68ff7204bca5e17a0241fe505ec7 (patch) | |
| tree | 26a8eea064fdf812d8412ccf90305cb7eaa59982 /mm | |
| parent | 1506c25508acd740ced5e92c539ed3d12f622c5b (diff) | |
mm: remove references to folio in split_page_memcg()
We know that the passed in page is not part of a folio (it's a plain page
allocated with GFP_ACCOUNT), so we should get rid of the misleading
references to folios.
Introduce page_objcg() and page_set_objcg() helpers to make things more
clear.
Link: https://lkml.kernel.org/r/20250314133617.138071-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/memcontrol.c | 30 |
1 files changed, 23 insertions, 7 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index fa7a3a1b710a..d95b1f4216ac 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2677,6 +2677,23 @@ out: return ret; } +static struct obj_cgroup *page_objcg(const struct page *page) +{ + unsigned long memcg_data = page->memcg_data; + + if (mem_cgroup_disabled() || !memcg_data) + return NULL; + + VM_BUG_ON_PAGE((memcg_data & OBJEXTS_FLAGS_MASK) != MEMCG_DATA_KMEM, + page); + return (struct obj_cgroup *)(memcg_data - MEMCG_DATA_KMEM); +} + +static void page_set_objcg(struct page *page, const struct obj_cgroup *objcg) +{ + page->memcg_data = (unsigned long)objcg | MEMCG_DATA_KMEM; +} + /** * __memcg_kmem_charge_page: charge a kmem page to the current memory cgroup * @page: page to charge @@ -2695,8 +2712,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) ret = obj_cgroup_charge_pages(objcg, gfp, 1 << order); if (!ret) { obj_cgroup_get(objcg); - page->memcg_data = (unsigned long)objcg | - MEMCG_DATA_KMEM; + page_set_objcg(page, objcg); return 0; } } @@ -3069,18 +3085,18 @@ void __memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, * The objcg is only set on the first page, so transfer it to all the * other pages. */ -void split_page_memcg(struct page *first, unsigned order) +void split_page_memcg(struct page *page, unsigned order) { - struct folio *folio = page_folio(first); + struct obj_cgroup *objcg = page_objcg(page); unsigned int i, nr = 1 << order; - if (mem_cgroup_disabled() || !folio_memcg_charged(folio)) + if (!objcg) return; for (i = 1; i < nr; i++) - folio_page(folio, i)->memcg_data = folio->memcg_data; + page_set_objcg(&page[i], objcg); - obj_cgroup_get_many(__folio_objcg(folio), nr - 1); + obj_cgroup_get_many(objcg, nr - 1); } void folio_split_memcg_refs(struct folio *folio, unsigned old_order, |