slub: Eliminate repeated use of c->page through a new page variable

__slab_alloc is full of "c->page" repeats. Lets just use one local variable
named "page" for this. Also avoids the need to a have another variable
called "new".

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/mm/slub.c b/mm/slub.c
index 837f932..ab44368 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1790,7 +1790,7 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
                          unsigned long addr, struct kmem_cache_cpu *c)
 {
        void **object;
-       struct page *new;
+       struct page *page;
 #ifdef CONFIG_CMPXCHG_LOCAL
        unsigned long flags;
 
@@ -1808,28 +1808,30 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
        /* We handle __GFP_ZERO in the caller */
        gfpflags &= ~__GFP_ZERO;
 
-       if (!c->page)
+       page = c->page;
+       if (!page)
                goto new_slab;
 
-       slab_lock(c->page);
+       slab_lock(page);
        if (unlikely(!node_match(c, node)))
                goto another_slab;
 
        stat(s, ALLOC_REFILL);
 
 load_freelist:
-       object = c->page->freelist;
+       object = page->freelist;
        if (unlikely(!object))
                goto another_slab;
        if (kmem_cache_debug(s))
                goto debug;
 
        c->freelist = get_freepointer(s, object);
-       c->page->inuse = c->page->objects;
-       c->page->freelist = NULL;
-       c->node = page_to_nid(c->page);
+       page->inuse = page->objects;
+       page->freelist = NULL;
+       c->node = page_to_nid(page);
+
 unlock_out:
-       slab_unlock(c->page);
+       slab_unlock(page);
 #ifdef CONFIG_CMPXCHG_LOCAL
        c->tid = next_tid(c->tid);
        local_irq_restore(flags);
@@ -1841,9 +1843,9 @@ another_slab:
        deactivate_slab(s, c);
 
 new_slab:
-       new = get_partial(s, gfpflags, node);
-       if (new) {
-               c->page = new;
+       page = get_partial(s, gfpflags, node);
+       if (page) {
+               c->page = page;
                stat(s, ALLOC_FROM_PARTIAL);
                goto load_freelist;
        }
@@ -1852,19 +1854,20 @@ new_slab:
        if (gfpflags & __GFP_WAIT)
                local_irq_enable();
 
-       new = new_slab(s, gfpflags, node);
+       page = new_slab(s, gfpflags, node);
 
        if (gfpflags & __GFP_WAIT)
                local_irq_disable();
 
-       if (new) {
+       if (page) {
                c = __this_cpu_ptr(s->cpu_slab);
                stat(s, ALLOC_SLAB);
                if (c->page)
                        flush_slab(s, c);
-               slab_lock(new);
-               __SetPageSlubFrozen(new);
-               c->page = new;
+
+               slab_lock(page);
+               __SetPageSlubFrozen(page);
+               c->page = page;
                goto load_freelist;
        }
        if (!(gfpflags & __GFP_NOWARN) && printk_ratelimit())
@@ -1874,11 +1877,11 @@ new_slab:
 #endif
        return NULL;
 debug:
-       if (!alloc_debug_processing(s, c->page, object, addr))
+       if (!alloc_debug_processing(s, page, object, addr))
                goto another_slab;
 
-       c->page->inuse++;
-       c->page->freelist = get_freepointer(s, object);
+       page->inuse++;
+       page->freelist = get_freepointer(s, object);
        c->node = NUMA_NO_NODE;
        goto unlock_out;
 }