[PATCH 48/62] mm/slub: Convert cmpxchg_double_slab to struct slab

["Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>]

Improve type safety for both cmpxchg_double_slab() and
__cmpxchg_double_slab().

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
 mm/slub.c | 46 +++++++++++++++++++++++-----------------------
 1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 72a50fab64b5..0d9299679ea2 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -448,7 +448,7 @@ static __always_inline void slab_unlock(struct page *page, unsigned long *flags)
  * by an _irqsave() lock variant. Except on PREEMPT_RT where locks are different
  * so we disable interrupts as part of slab_[un]lock().
  */
-static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
+static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab,
 		void *freelist_old, unsigned long counters_old,
 		void *freelist_new, unsigned long counters_new,
 		const char *n)
@@ -458,7 +458,7 @@ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page
 #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \
     defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE)
 	if (s->flags & __CMPXCHG_DOUBLE) {
-		if (cmpxchg_double(&page->freelist, &page->counters,
+		if (cmpxchg_double(&slab->freelist, &slab->counters,
 				   freelist_old, counters_old,
 				   freelist_new, counters_new))
 			return true;
@@ -468,15 +468,15 @@ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page
 		/* init to 0 to prevent spurious warnings */
 		unsigned long flags = 0;
 
-		slab_lock(page, &flags);
-		if (page->freelist == freelist_old &&
-					page->counters == counters_old) {
-			page->freelist = freelist_new;
-			page->counters = counters_new;
-			slab_unlock(page, &flags);
+		slab_lock(slab_page(slab), &flags);
+		if (slab->freelist == freelist_old &&
+					slab->counters == counters_old) {
+			slab->freelist = freelist_new;
+			slab->counters = counters_new;
+			slab_unlock(slab_page(slab), &flags);
 			return true;
 		}
-		slab_unlock(page, &flags);
+		slab_unlock(slab_page(slab), &flags);
 	}
 
 	cpu_relax();
@@ -489,7 +489,7 @@ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page
 	return false;
 }
 
-static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
+static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab,
 		void *freelist_old, unsigned long counters_old,
 		void *freelist_new, unsigned long counters_new,
 		const char *n)
@@ -497,7 +497,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
 #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \
     defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE)
 	if (s->flags & __CMPXCHG_DOUBLE) {
-		if (cmpxchg_double(&page->freelist, &page->counters,
+		if (cmpxchg_double(&slab->freelist, &slab->counters,
 				   freelist_old, counters_old,
 				   freelist_new, counters_new))
 			return true;
@@ -507,16 +507,16 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
 		unsigned long flags;
 
 		local_irq_save(flags);
-		__slab_lock(page);
-		if (page->freelist == freelist_old &&
-					page->counters == counters_old) {
-			page->freelist = freelist_new;
-			page->counters = counters_new;
-			__slab_unlock(page);
+		__slab_lock(slab_page(slab));
+		if (slab->freelist == freelist_old &&
+					slab->counters == counters_old) {
+			slab->freelist = freelist_new;
+			slab->counters = counters_new;
+			__slab_unlock(slab_page(slab));
 			local_irq_restore(flags);
 			return true;
 		}
-		__slab_unlock(page);
+		__slab_unlock(slab_page(slab));
 		local_irq_restore(flags);
 	}
 
@@ -2068,7 +2068,7 @@ static inline void *acquire_slab(struct kmem_cache *s,
 	VM_BUG_ON(new.frozen);
 	new.frozen = 1;
 
-	if (!__cmpxchg_double_slab(s, slab_page(slab),
+	if (!__cmpxchg_double_slab(s, slab,
 			freelist, counters,
 			new.freelist, new.counters,
 			"acquire_slab"))
@@ -2412,7 +2412,7 @@ static void deactivate_slab(struct kmem_cache *s, struct slab *slab,
 	}
 
 	l = m;
-	if (!cmpxchg_double_slab(s, slab_page(slab),
+	if (!cmpxchg_double_slab(s, slab,
 				old.freelist, old.counters,
 				new.freelist, new.counters,
 				"unfreezing slab"))
@@ -2466,7 +2466,7 @@ static void __unfreeze_partials(struct kmem_cache *s, struct slab *partial_slab)
 
 			new.frozen = 0;
 
-		} while (!__cmpxchg_double_slab(s, slab_page(slab),
+		} while (!__cmpxchg_double_slab(s, slab,
 				old.freelist, old.counters,
 				new.freelist, new.counters,
 				"unfreezing slab"));
@@ -2837,7 +2837,7 @@ static inline void *get_freelist(struct kmem_cache *s, struct slab *slab)
 		new.inuse = slab->objects;
 		new.frozen = freelist != NULL;
 
-	} while (!__cmpxchg_double_slab(s, slab_page(slab),
+	} while (!__cmpxchg_double_slab(s, slab,
 		freelist, counters,
 		NULL, new.counters,
 		"get_freelist"));
@@ -3329,7 +3329,7 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
 			}
 		}
 
-	} while (!cmpxchg_double_slab(s, slab_page(slab),
+	} while (!cmpxchg_double_slab(s, slab,
 		prior, counters,
 		head, new.counters,
 		"__slab_free"));
-- 
2.32.0