diff --git a/mm/slub.c b/mm/slub.c index 545a170ebf9f..2b1a6970e46f 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -355,6 +355,21 @@ static __always_inline void slab_unlock(struct page *page) __bit_spin_unlock(PG_locked, &page->flags); } +static inline void set_page_slub_counters(struct page *page, unsigned long counters_new) +{ + struct page tmp; + tmp.counters = counters_new; + /* + * page->counters can cover frozen/inuse/objects as well + * as page->_count. If we assign to ->counters directly + * we run the risk of losing updates to page->_count, so + * be careful and only assign to the fields we need. + */ + page->frozen = tmp.frozen; + page->inuse = tmp.inuse; + page->objects = tmp.objects; +} + /* Interrupts must be disabled (for the fallback code to work right) */ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page, void *freelist_old, unsigned long counters_old, @@ -376,7 +391,7 @@ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page if (page->freelist == freelist_old && page->counters == counters_old) { page->freelist = freelist_new; - page->counters = counters_new; + set_page_slub_counters(page, counters_new); slab_unlock(page); return 1; } @@ -415,7 +430,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page, if (page->freelist == freelist_old && page->counters == counters_old) { page->freelist = freelist_new; - page->counters = counters_new; + set_page_slub_counters(page, counters_new); slab_unlock(page); local_irq_restore(flags); return 1;