be2net: Minor code cleanup in tx completion process

- To avoid multiple accesses to CQE, extract compl_status and end_idx from
  be_tx_compl_get().

Signed-off-by: Sriharsha Basavapatna <sriharsha.basavapatna@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 31 insertions, 23 deletions

diff --git a/drivers/net/ethernet/emulex/benet/be.h b/drivers/net/ethernet/emulex/benet/be.h
index bc7f3d6872f4..ad33bf1f1df1 100644
--- a/drivers/net/ethernet/emulex/benet/be.h
+++ b/drivers/net/ethernet/emulex/benet/be.h
@@ -238,10 +238,17 @@ struct be_tx_stats {
         struct u64_stats_sync sync_compl;
 };
 
+/* Structure to hold some data of interest obtained from a TX CQE */
+struct be_tx_compl_info {
+        u8 status;              /* Completion status */
+        u16 end_index;          /* Completed TXQ Index */
+};
+
 struct be_tx_obj {
         u32 db_offset;
         struct be_queue_info q;
         struct be_queue_info cq;
+        struct be_tx_compl_info txcp;
         /* Remember the skbs that were transmitted */
         struct sk_buff *sent_skb_list[TX_Q_LEN];
         struct be_tx_stats stats;
diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index a6df4c96150f..78beab560bc0 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -2064,18 +2064,23 @@ static void be_post_rx_frags(struct be_rx_obj *rxo, gfp_t gfp, u32 frags_needed)
         }
 }
 
-static struct be_eth_tx_compl *be_tx_compl_get(struct be_queue_info *tx_cq)
+static struct be_tx_compl_info *be_tx_compl_get(struct be_tx_obj *txo)
 {
-        struct be_eth_tx_compl *txcp = queue_tail_node(tx_cq);
+        struct be_queue_info *tx_cq = &txo->cq;
+        struct be_tx_compl_info *txcp = &txo->txcp;
+        struct be_eth_tx_compl *compl = queue_tail_node(tx_cq);
 
-        if (txcp->dw[offsetof(struct amap_eth_tx_compl, valid) / 32] == 0)
+        if (compl->dw[offsetof(struct amap_eth_tx_compl, valid) / 32] == 0)
                 return NULL;
 
+        /* Ensure load ordering of valid bit dword and other dwords below */
         rmb();
-        be_dws_le_to_cpu(txcp, sizeof(*txcp));
+        be_dws_le_to_cpu(compl, sizeof(*compl));
 
-        txcp->dw[offsetof(struct amap_eth_tx_compl, valid) / 32] = 0;
+        txcp->status = GET_TX_COMPL_BITS(status, compl);
+        txcp->end_index = GET_TX_COMPL_BITS(wrb_index, compl);
 
+        compl->dw[offsetof(struct amap_eth_tx_compl, valid) / 32] = 0;
         queue_tail_inc(tx_cq);
         return txcp;
 }
@@ -2196,9 +2201,9 @@ static void be_tx_compl_clean(struct be_adapter *adapter)
 {
         u16 end_idx, notified_idx, cmpl = 0, timeo = 0, num_wrbs = 0;
         struct device *dev = &adapter->pdev->dev;
-        struct be_tx_obj *txo;
+        struct be_tx_compl_info *txcp;
         struct be_queue_info *txq;
-        struct be_eth_tx_compl *txcp;
+        struct be_tx_obj *txo;
         int i, pending_txqs;
 
         /* Stop polling for compls when HW has been silent for 10ms */
@@ -2209,10 +2214,10 @@ static void be_tx_compl_clean(struct be_adapter *adapter)
                         cmpl = 0;
                         num_wrbs = 0;
                         txq = &txo->q;
-                        while ((txcp = be_tx_compl_get(&txo->cq))) {
-                                end_idx = GET_TX_COMPL_BITS(wrb_index, txcp);
-                                num_wrbs += be_tx_compl_process(adapter, txo,
-                                                                end_idx);
+                        while ((txcp = be_tx_compl_get(txo))) {
+                                num_wrbs +=
+                                        be_tx_compl_process(adapter, txo,
+                                                            txcp->end_index);
                                 cmpl++;
                         }
                         if (cmpl) {
@@ -2571,7 +2576,7 @@ loop_continue:
         return work_done;
 }
 
-static inline void be_update_tx_err(struct be_tx_obj *txo, u32 status)
+static inline void be_update_tx_err(struct be_tx_obj *txo, u8 status)
 {
         switch (status) {
         case BE_TX_COMP_HDR_PARSE_ERR:
@@ -2586,7 +2591,7 @@ static inline void be_update_tx_err(struct be_tx_obj *txo, u32 status)
         }
 }
 
-static inline void lancer_update_tx_err(struct be_tx_obj *txo, u32 status)
+static inline void lancer_update_tx_err(struct be_tx_obj *txo, u8 status)
 {
         switch (status) {
         case LANCER_TX_COMP_LSO_ERR:
@@ -2611,22 +2616,18 @@ static inline void lancer_update_tx_err(struct be_tx_obj *txo, u32 status)
 static void be_process_tx(struct be_adapter *adapter, struct be_tx_obj *txo,
                           int idx)
 {
-        struct be_eth_tx_compl *txcp;
         int num_wrbs = 0, work_done = 0;
-        u32 compl_status;
-        u16 last_idx;
+        struct be_tx_compl_info *txcp;
 
-        while ((txcp = be_tx_compl_get(&txo->cq))) {
-                last_idx = GET_TX_COMPL_BITS(wrb_index, txcp);
-                num_wrbs += be_tx_compl_process(adapter, txo, last_idx);
+        while ((txcp = be_tx_compl_get(txo))) {
+                num_wrbs += be_tx_compl_process(adapter, txo, txcp->end_index);
                 work_done++;
 
-                compl_status = GET_TX_COMPL_BITS(status, txcp);
-                if (compl_status) {
+                if (txcp->status) {
                         if (lancer_chip(adapter))
-                                lancer_update_tx_err(txo, compl_status);
+                                lancer_update_tx_err(txo, txcp->status);
                         else
-                                be_update_tx_err(txo, compl_status);
+                                be_update_tx_err(txo, txcp->status);
                 }
         }