staging: zcache: optimize zcache_do_preload

zcache_do_preload is called in zcache_put_page where IRQ is disabled, so, need
not care preempt

Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c
index 0529b46..57e25fc 100644 (file)
--- a/drivers/staging/zcache/zcache-main.c
+++ b/drivers/staging/zcache/zcache-main.c
@@ -1031,45 +1031,43 @@ static int zcache_do_preload(struct tmem_pool *pool)
                goto out;
        if (unlikely(zcache_obj_cache == NULL))
                goto out;
-       preempt_disable();
+
+       /* IRQ has already been disabled. */
        kp = &__get_cpu_var(zcache_preloads);
        while (kp->nr < ARRAY_SIZE(kp->objnodes)) {
-               preempt_enable_no_resched();
                objnode = kmem_cache_alloc(zcache_objnode_cache,
                                ZCACHE_GFP_MASK);
                if (unlikely(objnode == NULL)) {
                        zcache_failed_alloc++;
                        goto out;
                }
-               preempt_disable();
-               kp = &__get_cpu_var(zcache_preloads);
-               if (kp->nr < ARRAY_SIZE(kp->objnodes))
-                       kp->objnodes[kp->nr++] = objnode;
-               else
-                       kmem_cache_free(zcache_objnode_cache, objnode);
+
+               kp->objnodes[kp->nr++] = objnode;
        }
-       preempt_enable_no_resched();
+
        obj = kmem_cache_alloc(zcache_obj_cache, ZCACHE_GFP_MASK);
        if (unlikely(obj == NULL)) {
                zcache_failed_alloc++;
                goto out;
        }
+
        page = (void *)__get_free_page(ZCACHE_GFP_MASK);
        if (unlikely(page == NULL)) {
                zcache_failed_get_free_pages++;
                kmem_cache_free(zcache_obj_cache, obj);
                goto out;
        }
-       preempt_disable();
-       kp = &__get_cpu_var(zcache_preloads);
+
        if (kp->obj == NULL)
                kp->obj = obj;
        else
                kmem_cache_free(zcache_obj_cache, obj);
+
        if (kp->page == NULL)
                kp->page = page;
        else
                free_page((unsigned long)page);
+
        ret = 0;
 out:
        return ret;
@@ -1580,7 +1578,6 @@ static int zcache_put_page(int cli_id, int pool_id, struct tmem_oid *oidp,
                                zcache_failed_pers_puts++;
                }
                zcache_put_pool(pool);
-               preempt_enable_no_resched();
        } else {
                zcache_put_to_flush++;
                if (atomic_read(&pool->obj_count) > 0)