bnx2: Optimize fast-path tx and rx work.

Add hw_tx_cons_ptr and hw_rx_cons_ptr to speed up the retreival of
the tx and rx consumer index, since the MSI-X and default status
blocks have different structures.

Combine status_blk and status_blk_msix into a union.  We'll only use
one type of status block for each vector.

Separate the code to detect more rx and tx work from the code to
detect link related work.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 72 insertions, 44 deletions

diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index 4360528ded39..3872e51b3c85 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -624,6 +624,7 @@ static void
 bnx2_free_mem(struct bnx2 *bp)
 {
         int i;
+        struct bnx2_napi *bnapi = &bp->bnx2_napi[0];
 
         bnx2_free_tx_mem(bp);
         bnx2_free_rx_mem(bp);
@@ -636,10 +637,11 @@ bnx2_free_mem(struct bnx2 *bp)
                         bp->ctx_blk[i] = NULL;
                 }
         }
-        if (bp->status_blk) {
+        if (bnapi->status_blk.msi) {
                 pci_free_consistent(bp->pdev, bp->status_stats_size,
-                                    bp->status_blk, bp->status_blk_mapping);
-                bp->status_blk = NULL;
+                                    bnapi->status_blk.msi,
+                                    bp->status_blk_mapping);
+                bnapi->status_blk.msi = NULL;
                 bp->stats_blk = NULL;
         }
 }
@@ -648,6 +650,8 @@ static int
 bnx2_alloc_mem(struct bnx2 *bp)
 {
         int i, status_blk_size, err;
+        struct bnx2_napi *bnapi;
+        void *status_blk;
 
         /* Combine status and statistics blocks into one allocation. */
         status_blk_size = L1_CACHE_ALIGN(sizeof(struct status_block));
@@ -657,27 +661,37 @@ bnx2_alloc_mem(struct bnx2 *bp)
         bp->status_stats_size = status_blk_size +
                                 sizeof(struct statistics_block);
 
-        bp->status_blk = pci_alloc_consistent(bp->pdev, bp->status_stats_size,
-                                              &bp->status_blk_mapping);
-        if (bp->status_blk == NULL)
+        status_blk = pci_alloc_consistent(bp->pdev, bp->status_stats_size,
+                                          &bp->status_blk_mapping);
+        if (status_blk == NULL)
                 goto alloc_mem_err;
 
-        memset(bp->status_blk, 0, bp->status_stats_size);
+        memset(status_blk, 0, bp->status_stats_size);
 
-        bp->bnx2_napi[0].status_blk = bp->status_blk;
+        bnapi = &bp->bnx2_napi[0];
+        bnapi->status_blk.msi = status_blk;
+        bnapi->hw_tx_cons_ptr =
+                &bnapi->status_blk.msi->status_tx_quick_consumer_index0;
+        bnapi->hw_rx_cons_ptr =
+                &bnapi->status_blk.msi->status_rx_quick_consumer_index0;
         if (bp->flags & BNX2_FLAG_MSIX_CAP) {
                 for (i = 1; i < BNX2_MAX_MSIX_VEC; i++) {
-                        struct bnx2_napi *bnapi = &bp->bnx2_napi[i];
+                        struct status_block_msix *sblk;
+
+                        bnapi = &bp->bnx2_napi[i];
 
-                        bnapi->status_blk_msix = (void *)
-                                ((unsigned long) bp->status_blk +
-                                 BNX2_SBLK_MSIX_ALIGN_SIZE * i);
+                        sblk = (void *) (status_blk +
+                                         BNX2_SBLK_MSIX_ALIGN_SIZE * i);
+                        bnapi->status_blk.msix = sblk;
+                        bnapi->hw_tx_cons_ptr =
+                                &sblk->status_tx_quick_consumer_index;
+                        bnapi->hw_rx_cons_ptr =
+                                &sblk->status_rx_quick_consumer_index;
                         bnapi->int_num = i << 24;
                 }
         }
 
-        bp->stats_blk = (void *) ((unsigned long) bp->status_blk +
-                                  status_blk_size);
+        bp->stats_blk = status_blk + status_blk_size;
 
         bp->stats_blk_mapping = bp->status_blk_mapping + status_blk_size;
 
@@ -2515,7 +2529,7 @@ bnx2_alloc_rx_skb(struct bnx2 *bp, struct bnx2_rx_ring_info *rxr, u16 index)
 static int
 bnx2_phy_event_is_set(struct bnx2 *bp, struct bnx2_napi *bnapi, u32 event)
 {
-        struct status_block *sblk = bnapi->status_blk;
+        struct status_block *sblk = bnapi->status_blk.msi;
         u32 new_link_state, old_link_state;
         int is_set = 1;
 
@@ -2551,11 +2565,9 @@ bnx2_get_hw_tx_cons(struct bnx2_napi *bnapi)
 {
         u16 cons;
 
-        if (bnapi->int_num == 0)
-                cons = bnapi->status_blk->status_tx_quick_consumer_index0;
-        else
-                cons = bnapi->status_blk_msix->status_tx_quick_consumer_index;
-
+        /* Tell compiler that status block fields can change. */
+        barrier();
+        cons = *bnapi->hw_tx_cons_ptr;
         if (unlikely((cons & MAX_TX_DESC_CNT) == MAX_TX_DESC_CNT))
                 cons++;
         return cons;
@@ -2822,11 +2834,9 @@ bnx2_get_hw_rx_cons(struct bnx2_napi *bnapi)
 {
         u16 cons;
 
-        if (bnapi->int_num == 0)
-                cons = bnapi->status_blk->status_rx_quick_consumer_index0;
-        else
-                cons = bnapi->status_blk_msix->status_rx_quick_consumer_index;
-
+        /* Tell compiler that status block fields can change. */
+        barrier();
+        cons = *bnapi->hw_rx_cons_ptr;
         if (unlikely((cons & MAX_RX_DESC_CNT) == MAX_RX_DESC_CNT))
                 cons++;
         return cons;
@@ -2990,7 +3000,7 @@ bnx2_msi(int irq, void *dev_instance)
         struct bnx2 *bp = netdev_priv(dev);
         struct bnx2_napi *bnapi = &bp->bnx2_napi[0];
 
-        prefetch(bnapi->status_blk);
+        prefetch(bnapi->status_blk.msi);
         REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD,
                 BNX2_PCICFG_INT_ACK_CMD_USE_INT_HC_PARAM |
                 BNX2_PCICFG_INT_ACK_CMD_MASK_INT);
@@ -3011,7 +3021,7 @@ bnx2_msi_1shot(int irq, void *dev_instance)
         struct bnx2 *bp = netdev_priv(dev);
         struct bnx2_napi *bnapi = &bp->bnx2_napi[0];
 
-        prefetch(bnapi->status_blk);
+        prefetch(bnapi->status_blk.msi);
 
         /* Return here if interrupt is disabled. */
         if (unlikely(atomic_read(&bp->intr_sem) != 0))
@@ -3028,7 +3038,7 @@ bnx2_interrupt(int irq, void *dev_instance)
         struct net_device *dev = dev_instance;
         struct bnx2 *bp = netdev_priv(dev);
         struct bnx2_napi *bnapi = &bp->bnx2_napi[0];
-        struct status_block *sblk = bnapi->status_blk;
+        struct status_block *sblk = bnapi->status_blk.msi;
 
         /* When using INTx, it is possible for the interrupt to arrive
          * at the CPU before the status block posted prior to the
@@ -3069,7 +3079,7 @@ bnx2_tx_msix(int irq, void *dev_instance)
         struct bnx2 *bp = netdev_priv(dev);
         struct bnx2_napi *bnapi = &bp->bnx2_napi[BNX2_TX_VEC];
 
-        prefetch(bnapi->status_blk_msix);
+        prefetch(bnapi->status_blk.msix);
 
         /* Return here if interrupt is disabled. */
         if (unlikely(atomic_read(&bp->intr_sem) != 0))
@@ -3079,19 +3089,28 @@ bnx2_tx_msix(int irq, void *dev_instance)
         return IRQ_HANDLED;
 }
 
-#define STATUS_ATTN_EVENTS      (STATUS_ATTN_BITS_LINK_STATE | \
-                                 STATUS_ATTN_BITS_TIMER_ABORT)
-
 static inline int
-bnx2_has_work(struct bnx2_napi *bnapi)
+bnx2_has_fast_work(struct bnx2_napi *bnapi)
 {
         struct bnx2_tx_ring_info *txr = &bnapi->tx_ring;
         struct bnx2_rx_ring_info *rxr = &bnapi->rx_ring;
-        struct status_block *sblk = bnapi->status_blk;
 
         if ((bnx2_get_hw_rx_cons(bnapi) != rxr->rx_cons) ||
             (bnx2_get_hw_tx_cons(bnapi) != txr->hw_tx_cons))
                 return 1;
+        return 0;
+}
+
+#define STATUS_ATTN_EVENTS      (STATUS_ATTN_BITS_LINK_STATE | \
+                                 STATUS_ATTN_BITS_TIMER_ABORT)
+
+static inline int
+bnx2_has_work(struct bnx2_napi *bnapi)
+{
+        struct status_block *sblk = bnapi->status_blk.msi;
+
+        if (bnx2_has_fast_work(bnapi))
+                return 1;
 
         if ((sblk->status_attn_bits & STATUS_ATTN_EVENTS) !=
             (sblk->status_attn_bits_ack & STATUS_ATTN_EVENTS))
@@ -3106,7 +3125,7 @@ static int bnx2_tx_poll(struct napi_struct *napi, int budget)
         struct bnx2 *bp = bnapi->bp;
         struct bnx2_tx_ring_info *txr = &bnapi->tx_ring;
         int work_done = 0;
-        struct status_block_msix *sblk = bnapi->status_blk_msix;
+        struct status_block_msix *sblk = bnapi->status_blk.msix;
 
         do {
                 work_done += bnx2_tx_int(bp, bnapi, budget - work_done);
@@ -3124,12 +3143,9 @@ static int bnx2_tx_poll(struct napi_struct *napi, int budget)
         return work_done;
 }
 
-static int bnx2_poll_work(struct bnx2 *bp, struct bnx2_napi *bnapi,
-                          int work_done, int budget)
+static void bnx2_poll_link(struct bnx2 *bp, struct bnx2_napi *bnapi)
 {
-        struct bnx2_tx_ring_info *txr = &bnapi->tx_ring;
-        struct bnx2_rx_ring_info *rxr = &bnapi->rx_ring;
-        struct status_block *sblk = bnapi->status_blk;
+        struct status_block *sblk = bnapi->status_blk.msi;
         u32 status_attn_bits = sblk->status_attn_bits;
         u32 status_attn_bits_ack = sblk->status_attn_bits_ack;
 
@@ -3145,6 +3161,13 @@ static int bnx2_poll_work(struct bnx2 *bp, struct bnx2_napi *bnapi,
                        bp->hc_cmd | BNX2_HC_COMMAND_COAL_NOW_WO_INT);
                 REG_RD(bp, BNX2_HC_COMMAND);
         }
+}
+
+static int bnx2_poll_work(struct bnx2 *bp, struct bnx2_napi *bnapi,
+                          int work_done, int budget)
+{
+        struct bnx2_tx_ring_info *txr = &bnapi->tx_ring;
+        struct bnx2_rx_ring_info *rxr = &bnapi->rx_ring;
 
         if (bnx2_get_hw_tx_cons(bnapi) != txr->hw_tx_cons)
                 bnx2_tx_int(bp, bnapi, 0);
@@ -3160,9 +3183,11 @@ static int bnx2_poll(struct napi_struct *napi, int budget)
         struct bnx2_napi *bnapi = container_of(napi, struct bnx2_napi, napi);
         struct bnx2 *bp = bnapi->bp;
         int work_done = 0;
-        struct status_block *sblk = bnapi->status_blk;
+        struct status_block *sblk = bnapi->status_blk.msi;
 
         while (1) {
+                bnx2_poll_link(bp, bnapi);
+
                 work_done = bnx2_poll_work(bp, bnapi, work_done, budget);
 
                 if (unlikely(work_done >= budget))
diff --git a/drivers/net/bnx2.h b/drivers/net/bnx2.h
index 1c5ce80f6269..362bef6ff5ff 100644
--- a/drivers/net/bnx2.h
+++ b/drivers/net/bnx2.h
@@ -6609,8 +6609,12 @@ struct bnx2_rx_ring_info {
 struct bnx2_napi {
         struct napi_struct      napi            ____cacheline_aligned;
         struct bnx2             *bp;
-        struct status_block     *status_blk;
-        struct status_block_msix        *status_blk_msix;
+        union {
+                struct status_block             *msi;
+                struct status_block_msix        *msix;
+        } status_blk;
+        u16                     *hw_tx_cons_ptr;
+        u16                     *hw_rx_cons_ptr;
         u32                     last_status_idx;
         u32                     int_num;
 
@@ -6759,7 +6763,6 @@ struct bnx2 {
 
         u32                     stats_ticks;
 
-        struct status_block     *status_blk;
         dma_addr_t              status_blk_mapping;
 
         struct statistics_block *stats_blk;