slab: replace free and inuse in struct slab with newly introduced active

Now, free in struct slab is same meaning as inuse.
So, remove both and replace them with active.

Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>

1 files changed, 25 insertions, 29 deletions

diff --git a/mm/slab.c b/mm/slab.c
index c271d5b71093..2ec2336a1ffc 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -174,8 +174,7 @@ struct slab {
         struct {
                 struct list_head list;
                 void *s_mem;            /* including colour offset */
-                unsigned int inuse;     /* num of objs active in slab */
-                unsigned int free;
+                unsigned int active;    /* num of objs active in slab */
         };
 };
 
@@ -1658,7 +1657,7 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
                         active_slabs++;
                 }
                 list_for_each_entry(slabp, &n->slabs_partial, list) {
-                        active_objs += slabp->inuse;
+                        active_objs += slabp->active;
                         active_slabs++;
                 }
                 list_for_each_entry(slabp, &n->slabs_free, list)
@@ -2451,7 +2450,7 @@ static int drain_freelist(struct kmem_cache *cache,
 
                 slabp = list_entry(p, struct slab, list);
 #if DEBUG
-                BUG_ON(slabp->inuse);
+                BUG_ON(slabp->active);
 #endif
                 list_del(&slabp->list);
                 /*
@@ -2570,9 +2569,8 @@ static struct slab *alloc_slabmgmt(struct kmem_cache *cachep,
                 slabp = addr + colour_off;
                 colour_off += cachep->slab_size;
         }
-        slabp->inuse = 0;
+        slabp->active = 0;
         slabp->s_mem = addr + colour_off;
-        slabp->free = 0;
         return slabp;
 }
 
@@ -2642,12 +2640,11 @@ static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp,
 {
         void *objp;
 
-        slabp->inuse++;
-        objp = index_to_obj(cachep, slabp, slab_bufctl(slabp)[slabp->free]);
+        objp = index_to_obj(cachep, slabp, slab_bufctl(slabp)[slabp->active]);
+        slabp->active++;
 #if DEBUG
         WARN_ON(page_to_nid(virt_to_page(objp)) != nodeid);
 #endif
-        slabp->free++;
 
         return objp;
 }
@@ -2663,7 +2660,7 @@ static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp,
         WARN_ON(page_to_nid(virt_to_page(objp)) != nodeid);
 
         /* Verify double free bug */
-        for (i = slabp->free; i < cachep->num; i++) {
+        for (i = slabp->active; i < cachep->num; i++) {
                 if (slab_bufctl(slabp)[i] == objnr) {
                         printk(KERN_ERR "slab: double free detected in cache "
                                         "'%s', objp %p\n", cachep->name, objp);
@@ -2671,9 +2668,8 @@ static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp,
                 }
         }
 #endif
-        slabp->free--;
-        slab_bufctl(slabp)[slabp->free] = objnr;
-        slabp->inuse--;
+        slabp->active--;
+        slab_bufctl(slabp)[slabp->active] = objnr;
 }
 
 /*
@@ -2908,9 +2904,9 @@ retry:
                  * there must be at least one object available for
                  * allocation.
                  */
-                BUG_ON(slabp->inuse >= cachep->num);
+                BUG_ON(slabp->active >= cachep->num);
 
-                while (slabp->inuse < cachep->num && batchcount--) {
+                while (slabp->active < cachep->num && batchcount--) {
                         STATS_INC_ALLOCED(cachep);
                         STATS_INC_ACTIVE(cachep);
                         STATS_SET_HIGH(cachep);
@@ -2921,7 +2917,7 @@ retry:
 
                 /* move slabp to correct slabp list: */
                 list_del(&slabp->list);
-                if (slabp->free == cachep->num)
+                if (slabp->active == cachep->num)
                         list_add(&slabp->list, &n->slabs_full);
                 else
                         list_add(&slabp->list, &n->slabs_partial);
@@ -3206,14 +3202,14 @@ retry:
         STATS_INC_ACTIVE(cachep);
         STATS_SET_HIGH(cachep);
 
-        BUG_ON(slabp->inuse == cachep->num);
+        BUG_ON(slabp->active == cachep->num);
 
         obj = slab_get_obj(cachep, slabp, nodeid);
         n->free_objects--;
         /* move slabp to correct slabp list: */
         list_del(&slabp->list);
 
-        if (slabp->free == cachep->num)
+        if (slabp->active == cachep->num)
                 list_add(&slabp->list, &n->slabs_full);
         else
                 list_add(&slabp->list, &n->slabs_partial);
@@ -3380,7 +3376,7 @@ static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects,
                 n->free_objects++;
 
                 /* fixup slab chains */
-                if (slabp->inuse == 0) {
+                if (slabp->active == 0) {
                         if (n->free_objects > n->free_limit) {
                                 n->free_objects -= cachep->num;
                                 /* No need to drop any previously held
@@ -3441,7 +3437,7 @@ free_done:
                         struct slab *slabp;
 
                         slabp = list_entry(p, struct slab, list);
-                        BUG_ON(slabp->inuse);
+                        BUG_ON(slabp->active);
 
                         i++;
                         p = p->next;
@@ -4066,22 +4062,22 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
                 spin_lock_irq(&n->list_lock);
 
                 list_for_each_entry(slabp, &n->slabs_full, list) {
-                        if (slabp->inuse != cachep->num && !error)
+                        if (slabp->active != cachep->num && !error)
                                 error = "slabs_full accounting error";
                         active_objs += cachep->num;
                         active_slabs++;
                 }
                 list_for_each_entry(slabp, &n->slabs_partial, list) {
-                        if (slabp->inuse == cachep->num && !error)
-                                error = "slabs_partial inuse accounting error";
-                        if (!slabp->inuse && !error)
-                                error = "slabs_partial/inuse accounting error";
-                        active_objs += slabp->inuse;
+                        if (slabp->active == cachep->num && !error)
+                                error = "slabs_partial accounting error";
+                        if (!slabp->active && !error)
+                                error = "slabs_partial accounting error";
+                        active_objs += slabp->active;
                         active_slabs++;
                 }
                 list_for_each_entry(slabp, &n->slabs_free, list) {
-                        if (slabp->inuse && !error)
-                                error = "slabs_free/inuse accounting error";
+                        if (slabp->active && !error)
+                                error = "slabs_free accounting error";
                         num_slabs++;
                 }
                 free_objects += n->free_objects;
@@ -4243,7 +4239,7 @@ static void handle_slab(unsigned long *n, struct kmem_cache *c, struct slab *s)
         for (i = 0, p = s->s_mem; i < c->num; i++, p += c->size) {
                 bool active = true;
 
-                for (j = s->free; j < c->num; j++) {
+                for (j = s->active; j < c->num; j++) {
                         /* Skip freed item */
                         if (slab_bufctl(s)[j] == i) {
                                 active = false;