wireless: a global static to local static improvement

There are two improvements in this simple patch:
1. wiphy_counter is a static var only used in one function, so
   can use local static instead of global static;
2. wiphy_counter wrap handling killed one comparision;

Signed-off-by: Denis ChengRq <crquan@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/wireless/core.c b/net/wireless/core.c
index d6940085d59c33c6e3e6000abe01d928adddd478..5cadbeb76a1430ca30d0b1faff578f83807057e5 100644 (file)
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -34,7 +34,6 @@ MODULE_DESCRIPTION("wireless configuration support");
  * often because we need to do it for each command */
 LIST_HEAD(cfg80211_drv_list);
 DEFINE_MUTEX(cfg80211_drv_mutex);
-static int wiphy_counter;
 
 /* for debugfs */
 static struct dentry *ieee80211_debugfs_dir;
@@ -206,6 +205,8 @@ out_unlock:
 
 struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
 {
+       static int wiphy_counter;
+
        struct cfg80211_registered_device *drv;
        int alloc_size;
 
@@ -222,21 +223,18 @@ struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
 
        mutex_lock(&cfg80211_drv_mutex);
 
-       drv->idx = wiphy_counter;
-
-       /* now increase counter for the next device unless
-        * it has wrapped previously */
-       if (wiphy_counter >= 0)
-               wiphy_counter++;
-
-       mutex_unlock(&cfg80211_drv_mutex);
+       drv->idx = wiphy_counter++;
 
        if (unlikely(drv->idx < 0)) {
+               wiphy_counter--;
+               mutex_unlock(&cfg80211_drv_mutex);
                /* ugh, wrapped! */
                kfree(drv);
                return NULL;
        }
 
+       mutex_unlock(&cfg80211_drv_mutex);
+
        /* give it a proper name */
        snprintf(drv->wiphy.dev.bus_id, BUS_ID_SIZE,
                 PHY_NAME "%d", drv->idx);