mwifiex: rework round robin scheduling of bss nodes.
authorAndreas Fenkart <[andreas.fenkart@streamunlimited.com]>
Thu, 18 Apr 2013 23:34:12 +0000 (16:34 -0700)
committerJohn W. Linville <linville@tuxdriver.com>
Tue, 23 Apr 2013 19:18:40 +0000 (15:18 -0400)
Rotate bss prio list, so the bss next to the one served, will come first
in the list of bss' with equal priority. This way we pick bss nodes in a
round robin fashion. Using list rotation instead of a cur ptr simplifies
iteration to calling list_for_each_entry. List rotation is done via
list_move, where the head itself is temporarily removed and then
re-inserted after the bss just served.

Signed-off-by: Andreas Fenkart <andreas.fenkart@streamunlimited.com>
Acked-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
drivers/net/wireless/mwifiex/11n_aggr.c
drivers/net/wireless/mwifiex/init.c
drivers/net/wireless/mwifiex/wmm.c

index c6d7451..a78e065 100644 (file)
@@ -297,12 +297,6 @@ mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
        }
        if (ret != -EBUSY) {
                mwifiex_rotate_priolists(priv, pra_list, ptrindex);
-               /* Now bss_prio_cur pointer points to next node */
-               adapter->bss_prio_tbl[priv->bss_priority].bss_prio_cur =
-                       list_first_entry(
-                               &adapter->bss_prio_tbl[priv->bss_priority]
-                               .bss_prio_cur->list,
-                               struct mwifiex_bss_prio_node, list);
        }
 
        return 0;
index 42d7f0a..9f44fda 100644 (file)
@@ -44,8 +44,6 @@ static int mwifiex_add_bss_prio_tbl(struct mwifiex_private *priv)
 
        bss_prio->priv = priv;
        INIT_LIST_HEAD(&bss_prio->list);
-       if (!tbl[priv->bss_priority].bss_prio_cur)
-               tbl[priv->bss_priority].bss_prio_cur = bss_prio;
 
        spin_lock_irqsave(&tbl[priv->bss_priority].bss_prio_lock, flags);
        list_add_tail(&bss_prio->list, &tbl[priv->bss_priority].bss_prio_head);
@@ -525,7 +523,6 @@ int mwifiex_init_lock_list(struct mwifiex_adapter *adapter)
 
        for (i = 0; i < adapter->priv_num; ++i) {
                INIT_LIST_HEAD(&adapter->bss_prio_tbl[i].bss_prio_head);
-               adapter->bss_prio_tbl[i].bss_prio_cur = NULL;
                spin_lock_init(&adapter->bss_prio_tbl[i].bss_prio_lock);
        }
 
@@ -625,42 +622,36 @@ static void mwifiex_delete_bss_prio_tbl(struct mwifiex_private *priv)
 {
        int i;
        struct mwifiex_adapter *adapter = priv->adapter;
-       struct mwifiex_bss_prio_node *bssprio_node, *tmp_node, **cur;
+       struct mwifiex_bss_prio_node *bssprio_node, *tmp_node;
        struct list_head *head;
        spinlock_t *lock; /* bss priority lock */
        unsigned long flags;
 
        for (i = 0; i < adapter->priv_num; ++i) {
                head = &adapter->bss_prio_tbl[i].bss_prio_head;
-               cur = &adapter->bss_prio_tbl[i].bss_prio_cur;
                lock = &adapter->bss_prio_tbl[i].bss_prio_lock;
                dev_dbg(adapter->dev, "info: delete BSS priority table,"
                                " bss_type = %d, bss_num = %d, i = %d,"
-                               " head = %p, cur = %p\n",
-                             priv->bss_type, priv->bss_num, i, head, *cur);
-               if (*cur) {
+                               " head = %p\n",
+                             priv->bss_type, priv->bss_num, i, head);
+
+               {
                        spin_lock_irqsave(lock, flags);
                        if (list_empty(head)) {
                                spin_unlock_irqrestore(lock, flags);
                                continue;
                        }
-                       bssprio_node = list_first_entry(head,
-                                       struct mwifiex_bss_prio_node, list);
-                       spin_unlock_irqrestore(lock, flags);
-
                        list_for_each_entry_safe(bssprio_node, tmp_node, head,
                                                 list) {
                                if (bssprio_node->priv == priv) {
                                        dev_dbg(adapter->dev, "info: Delete "
                                                "node %p, next = %p\n",
                                                bssprio_node, tmp_node);
-                                       spin_lock_irqsave(lock, flags);
                                        list_del(&bssprio_node->list);
-                                       spin_unlock_irqrestore(lock, flags);
                                        kfree(bssprio_node);
                                }
                        }
-                       *cur = (struct mwifiex_bss_prio_node *)head;
+                       spin_unlock_irqrestore(lock, flags);
                }
        }
 }
index b48e03c..4be3d33 100644 (file)
@@ -878,37 +878,25 @@ mwifiex_wmm_get_highest_priolist_ptr(struct mwifiex_adapter *adapter,
 {
        struct mwifiex_private *priv_tmp;
        struct mwifiex_ra_list_tbl *ptr;
-       struct mwifiex_bss_prio_node *bssprio_node, *bssprio_head;
        struct mwifiex_tid_tbl *tid_ptr;
        atomic_t *hqp;
        unsigned long flags_bss, flags_ra;
        int i, j;
 
+       /* check the BSS with highest priority first */
        for (j = adapter->priv_num - 1; j >= 0; --j) {
                spin_lock_irqsave(&adapter->bss_prio_tbl[j].bss_prio_lock,
                                  flags_bss);
 
-               if (list_empty(&adapter->bss_prio_tbl[j].bss_prio_head))
-                       goto skip_prio_tbl;
-
-               if (adapter->bss_prio_tbl[j].bss_prio_cur ==
-                   (struct mwifiex_bss_prio_node *)
-                   &adapter->bss_prio_tbl[j].bss_prio_head) {
-                       adapter->bss_prio_tbl[j].bss_prio_cur =
-                               list_first_entry(&adapter->bss_prio_tbl[j]
-                                                .bss_prio_head,
-                                                struct mwifiex_bss_prio_node,
-                                                list);
-               }
-
-               bssprio_node = adapter->bss_prio_tbl[j].bss_prio_cur;
-               bssprio_head = bssprio_node;
+               /* iterate over BSS with the equal priority */
+               list_for_each_entry(adapter->bss_prio_tbl[j].bss_prio_cur,
+                                   &adapter->bss_prio_tbl[j].bss_prio_head,
+                                   list) {
 
-               do {
-                       priv_tmp = bssprio_node->priv;
+                       priv_tmp = adapter->bss_prio_tbl[j].bss_prio_cur->priv;
 
                        if (atomic_read(&priv_tmp->wmm.tx_pkts_queued) == 0)
-                               goto skip_bss;
+                               continue;
 
                        /* iterate over the WMM queues of the BSS */
                        hqp = &priv_tmp->wmm.highest_queued_prio;
@@ -933,24 +921,8 @@ mwifiex_wmm_get_highest_priolist_ptr(struct mwifiex_adapter *adapter,
                                                       ra_list_spinlock,
                                                       flags_ra);
                        }
+               }
 
-skip_bss:
-                       /* Get next bss priority node */
-                       bssprio_node = list_first_entry(&bssprio_node->list,
-                                               struct mwifiex_bss_prio_node,
-                                               list);
-
-                       if (bssprio_node ==
-                           (struct mwifiex_bss_prio_node *)
-                           &adapter->bss_prio_tbl[j].bss_prio_head)
-                               /* Get next bss priority node */
-                               bssprio_node = list_first_entry(
-                                               &bssprio_node->list,
-                                               struct mwifiex_bss_prio_node,
-                                               list);
-               } while (bssprio_node != bssprio_head);
-
-skip_prio_tbl:
                spin_unlock_irqrestore(&adapter->bss_prio_tbl[j].bss_prio_lock,
                                       flags_bss);
        }
@@ -971,12 +943,12 @@ found:
        return ptr;
 }
 
-/* This functions rotates ra lists so packets are picked in round robin
- * fashion.
+/* This functions rotates ra and bss lists so packets are picked round robin.
  *
  * After a packet is successfully transmitted, rotate the ra list, so the ra
  * next to the one transmitted, will come first in the list. This way we pick
- * the ra in a round robin fashion.
+ * the ra' in a round robin fashion. Same applies to bss nodes of equal
+ * priority.
  *
  * Function also increments wmm.packets_out counter.
  */
@@ -984,17 +956,24 @@ void mwifiex_rotate_priolists(struct mwifiex_private *priv,
                                 struct mwifiex_ra_list_tbl *ra,
                                 int tid)
 {
+       struct mwifiex_adapter *adapter = priv->adapter;
+       struct mwifiex_bss_prio_tbl *tbl = adapter->bss_prio_tbl;
        struct mwifiex_tid_tbl *tid_ptr = &priv->wmm.tid_tbl_ptr[tid];
        unsigned long flags;
 
+       spin_lock_irqsave(&tbl[priv->bss_priority].bss_prio_lock, flags);
+       /*
+        * dirty trick: we remove 'head' temporarily and reinsert it after
+        * curr bss node. imagine list to stay fixed while head is moved
+        */
+       list_move(&tbl[priv->bss_priority].bss_prio_head,
+                 &tbl[priv->bss_priority].bss_prio_cur->list);
+       spin_unlock_irqrestore(&tbl[priv->bss_priority].bss_prio_lock, flags);
+
        spin_lock_irqsave(&priv->wmm.ra_list_spinlock, flags);
        if (mwifiex_is_ralist_valid(priv, ra, tid)) {
                priv->wmm.packets_out[tid]++;
-               /*
-                * dirty trick: we remove 'head' temporarily and reinsert it
-                * after curr bss node. imagine list to stay fixed while only
-                * head is moved
-                */
+               /* same as above */
                list_move(&tid_ptr->ra_list, &ra->list);
        }
        spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, flags);
@@ -1087,12 +1066,6 @@ mwifiex_send_single_packet(struct mwifiex_private *priv,
                                       ra_list_flags);
        } else {
                mwifiex_rotate_priolists(priv, ptr, ptr_index);
-               adapter->bss_prio_tbl[priv->bss_priority].bss_prio_cur =
-                       list_first_entry(
-                               &adapter->bss_prio_tbl[priv->bss_priority]
-                               .bss_prio_cur->list,
-                               struct mwifiex_bss_prio_node,
-                               list);
                atomic_dec(&priv->wmm.tx_pkts_queued);
        }
 }
@@ -1198,12 +1171,6 @@ mwifiex_send_processed_packet(struct mwifiex_private *priv,
        }
        if (ret != -EBUSY) {
                mwifiex_rotate_priolists(priv, ptr, ptr_index);
-               adapter->bss_prio_tbl[priv->bss_priority].bss_prio_cur =
-                       list_first_entry(
-                               &adapter->bss_prio_tbl[priv->bss_priority]
-                               .bss_prio_cur->list,
-                               struct mwifiex_bss_prio_node,
-                               list);
                atomic_dec(&priv->wmm.tx_pkts_queued);
        }
 }