wifi: mac80211: mlme: look up beacon elems only if needed

If NEED_DTIM_BEFORE_ASSOC isn't set, then we don't need
to enter an RCU critical section and look up the beacon
elements.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 292ad46daa9da619c0710fcc764bf1877464d694..059b66d158ff6b3942863fd4595f6a236e5f138d 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -6270,7 +6270,6 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
        struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
        struct ieee80211_bss *bss = (void *)req->bss->priv;
        struct ieee80211_mgd_assoc_data *assoc_data;
-       const struct cfg80211_bss_ies *beacon_ies;
        struct ieee80211_vif_cfg *vif_cfg = &sdata->vif.cfg;
        const struct element *ssid_elem;
        struct ieee80211_link_data *link = &sdata->deflink;
@@ -6488,22 +6487,25 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
                link->smps_mode = link->u.mgd.req_smps;
        }
 
-       rcu_read_lock();
-       beacon_ies = rcu_dereference(req->bss->beacon_ies);
+       if (ieee80211_hw_check(&sdata->local->hw, NEED_DTIM_BEFORE_ASSOC)) {
+               const struct cfg80211_bss_ies *beacon_ies;
 
-       if (ieee80211_hw_check(&sdata->local->hw, NEED_DTIM_BEFORE_ASSOC) &&
-           !beacon_ies) {
-               /*
-                * Wait up to one beacon interval ...
-                * should this be more if we miss one?
-                */
-               sdata_info(sdata, "waiting for beacon from %pM\n",
-                          link->u.mgd.bssid);
-               assoc_data->timeout = TU_TO_EXP_TIME(req->bss->beacon_interval);
-               assoc_data->timeout_started = true;
-               assoc_data->need_beacon = true;
+               rcu_read_lock();
+               beacon_ies = rcu_dereference(req->bss->beacon_ies);
+
+               if (beacon_ies) {
+                       /*
+                        * Wait up to one beacon interval ...
+                        * should this be more if we miss one?
+                        */
+                       sdata_info(sdata, "waiting for beacon from %pM\n",
+                                  link->u.mgd.bssid);
+                       assoc_data->timeout = TU_TO_EXP_TIME(req->bss->beacon_interval);
+                       assoc_data->timeout_started = true;
+                       assoc_data->need_beacon = true;
+               }
+               rcu_read_unlock();
        }
-       rcu_read_unlock();
 
        run_again(sdata, assoc_data->timeout);