mm/slub: Convert deactivate_slab() to take a struct slab

Improves type safety and removes calls to slab_page().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

diff --git a/mm/slub.c b/mm/slub.c
index e6fd0619d1f28ecbe509025c6aaee293aa5a0ac5..5330d0b02f13d97c2ba63ee0c63ae7db95a427e1 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2298,25 +2298,25 @@ static void init_kmem_cache_cpus(struct kmem_cache *s)
 }
 
 /*
- * Finishes removing the cpu slab. Merges cpu's freelist with page's freelist,
+ * Finishes removing the cpu slab. Merges cpu's freelist with slab's freelist,
  * unfreezes the slabs and puts it on the proper list.
  * Assumes the slab has been already safely taken away from kmem_cache_cpu
  * by the caller.
  */
-static void deactivate_slab(struct kmem_cache *s, struct page *page,
+static void deactivate_slab(struct kmem_cache *s, struct slab *slab,
                            void *freelist)
 {
        enum slab_modes { M_NONE, M_PARTIAL, M_FULL, M_FREE };
-       struct kmem_cache_node *n = get_node(s, page_to_nid(page));
+       struct kmem_cache_node *n = get_node(s, slab_nid(slab));
        int lock = 0, free_delta = 0;
        enum slab_modes l = M_NONE, m = M_NONE;
        void *nextfree, *freelist_iter, *freelist_tail;
        int tail = DEACTIVATE_TO_HEAD;
        unsigned long flags = 0;
-       struct page new;
-       struct page old;
+       struct slab new;
+       struct slab old;
 
-       if (page->freelist) {
+       if (slab->freelist) {
                stat(s, DEACTIVATE_REMOTE_FREES);
                tail = DEACTIVATE_TO_TAIL;
        }
@@ -2335,7 +2335,7 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
                 * 'freelist_iter' is already corrupted.  So isolate all objects
                 * starting at 'freelist_iter' by skipping them.
                 */
-               if (freelist_corrupted(s, page, &freelist_iter, nextfree))
+               if (freelist_corrupted(s, slab_page(slab), &freelist_iter, nextfree))
                        break;
 
                freelist_tail = freelist_iter;
@@ -2345,25 +2345,25 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
        }
 
        /*
-        * Stage two: Unfreeze the page while splicing the per-cpu
-        * freelist to the head of page's freelist.
+        * Stage two: Unfreeze the slab while splicing the per-cpu
+        * freelist to the head of slab's freelist.
         *
-        * Ensure that the page is unfrozen while the list presence
+        * Ensure that the slab is unfrozen while the list presence
         * reflects the actual number of objects during unfreeze.
         *
         * We setup the list membership and then perform a cmpxchg
-        * with the count. If there is a mismatch then the page
-        * is not unfrozen but the page is on the wrong list.
+        * with the count. If there is a mismatch then the slab
+        * is not unfrozen but the slab is on the wrong list.
         *
         * Then we restart the process which may have to remove
-        * the page from the list that we just put it on again
+        * the slab from the list that we just put it on again
         * because the number of objects in the slab may have
         * changed.
         */
 redo:
 
-       old.freelist = READ_ONCE(page->freelist);
-       old.counters = READ_ONCE(page->counters);
+       old.freelist = READ_ONCE(slab->freelist);
+       old.counters = READ_ONCE(slab->counters);
        VM_BUG_ON(!old.frozen);
 
        /* Determine target state of the slab */
@@ -2385,7 +2385,7 @@ redo:
                        lock = 1;
                        /*
                         * Taking the spinlock removes the possibility
-                        * that acquire_slab() will see a slab page that
+                        * that acquire_slab() will see a slab that
                         * is frozen
                         */
                        spin_lock_irqsave(&n->list_lock, flags);
@@ -2405,18 +2405,18 @@ redo:
 
        if (l != m) {
                if (l == M_PARTIAL)
-                       remove_partial(n, page);
+                       remove_partial(n, slab_page(slab));
                else if (l == M_FULL)
-                       remove_full(s, n, page);
+                       remove_full(s, n, slab_page(slab));
 
                if (m == M_PARTIAL)
-                       add_partial(n, page, tail);
+                       add_partial(n, slab_page(slab), tail);
                else if (m == M_FULL)
-                       add_full(s, n, page);
+                       add_full(s, n, slab_page(slab));
        }
 
        l = m;
-       if (!cmpxchg_double_slab(s, page,
+       if (!cmpxchg_double_slab(s, slab_page(slab),
                                old.freelist, old.counters,
                                new.freelist, new.counters,
                                "unfreezing slab"))
@@ -2431,7 +2431,7 @@ redo:
                stat(s, DEACTIVATE_FULL);
        else if (m == M_FREE) {
                stat(s, DEACTIVATE_EMPTY);
-               discard_slab(s, page);
+               discard_slab(s, slab_page(slab));
                stat(s, FREE_SLAB);
        }
 }
@@ -2603,7 +2603,7 @@ static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
        local_unlock_irqrestore(&s->cpu_slab->lock, flags);
 
        if (slab) {
-               deactivate_slab(s, slab_page(slab), freelist);
+               deactivate_slab(s, slab, freelist);
                stat(s, CPUSLAB_FLUSH);
        }
 }
@@ -2619,7 +2619,7 @@ static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
        c->tid = next_tid(c->tid);
 
        if (slab) {
-               deactivate_slab(s, slab_page(slab), freelist);
+               deactivate_slab(s, slab, freelist);
                stat(s, CPUSLAB_FLUSH);
        }
 
@@ -2961,7 +2961,7 @@ deactivate_slab:
        c->slab = NULL;
        c->freelist = NULL;
        local_unlock_irqrestore(&s->cpu_slab->lock, flags);
-       deactivate_slab(s, slab_page(slab), freelist);
+       deactivate_slab(s, slab, freelist);
 
 new_slab:
 
@@ -3043,7 +3043,7 @@ retry_load_slab:
 
                local_unlock_irqrestore(&s->cpu_slab->lock, flags);
 
-               deactivate_slab(s, slab_page(flush_slab), flush_freelist);
+               deactivate_slab(s, flush_slab, flush_freelist);
 
                stat(s, CPUSLAB_FLUSH);
 
@@ -3055,7 +3055,7 @@ retry_load_slab:
 
 return_single:
 
-       deactivate_slab(s, slab_page(slab), get_freepointer(s, freelist));
+       deactivate_slab(s, slab, get_freepointer(s, freelist));
        return freelist;
 }