[e1000] s/int/unsigned int/ for descriptor ring indexes

* Perf cleanup: s/int/unsigned int/ for descriptor ring indexes
  [suggestion by Jeff Garzik].
* Perf cleanup: cache references to ring elements using local pointer

diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index 7be87ec92fe3c6e8a3b954ab0355659b338a6ba6..390795a115c13406c4e6c018551cceb2ed251f1a 100644 (file)
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -977,35 +977,38 @@ e1000_free_tx_resources(struct e1000_adapter *adapter)
 static void
 e1000_clean_tx_ring(struct e1000_adapter *adapter)
 {
+       struct e1000_desc_ring *tx_ring = &adapter->tx_ring;
+       struct e1000_buffer *buffer_info;
        struct pci_dev *pdev = adapter->pdev;
        unsigned long size;
-       int i;
+       unsigned int i;
 
        /* Free all the Tx ring sk_buffs */
 
-       for(i = 0; i < adapter->tx_ring.count; i++) {
-               if(adapter->tx_ring.buffer_info[i].skb) {
+       for(i = 0; i < tx_ring->count; i++) {
+               buffer_info = &tx_ring->buffer_info[i];
+               if(buffer_info->skb) {
 
                        pci_unmap_page(pdev,
-                                      adapter->tx_ring.buffer_info[i].dma,
-                                      adapter->tx_ring.buffer_info[i].length,
+                                      buffer_info->dma,
+                                      buffer_info->length,
                                       PCI_DMA_TODEVICE);
 
-                       dev_kfree_skb(adapter->tx_ring.buffer_info[i].skb);
+                       dev_kfree_skb(buffer_info->skb);
 
-                       adapter->tx_ring.buffer_info[i].skb = NULL;
+                       buffer_info->skb = NULL;
                }
        }
 
-       size = sizeof(struct e1000_buffer) * adapter->tx_ring.count;
-       memset(adapter->tx_ring.buffer_info, 0, size);
+       size = sizeof(struct e1000_buffer) * tx_ring->count;
+       memset(tx_ring->buffer_info, 0, size);
 
        /* Zero out the descriptor ring */
 
-       memset(adapter->tx_ring.desc, 0, adapter->tx_ring.size);
+       memset(tx_ring->desc, 0, tx_ring->size);
 
-       adapter->tx_ring.next_to_use = 0;
-       adapter->tx_ring.next_to_clean = 0;
+       tx_ring->next_to_use = 0;
+       tx_ring->next_to_clean = 0;
 
        E1000_WRITE_REG(&adapter->hw, TDH, 0);
        E1000_WRITE_REG(&adapter->hw, TDT, 0);
@@ -1021,17 +1024,17 @@ e1000_clean_tx_ring(struct e1000_adapter *adapter)
 static void
 e1000_free_rx_resources(struct e1000_adapter *adapter)
 {
+       struct e1000_desc_ring *rx_ring = &adapter->rx_ring;
        struct pci_dev *pdev = adapter->pdev;
 
        e1000_clean_rx_ring(adapter);
 
-       kfree(adapter->rx_ring.buffer_info);
-       adapter->rx_ring.buffer_info = NULL;
+       kfree(rx_ring->buffer_info);
+       rx_ring->buffer_info = NULL;
 
-       pci_free_consistent(pdev, adapter->rx_ring.size,
-                           adapter->rx_ring.desc, adapter->rx_ring.dma);
+       pci_free_consistent(pdev, rx_ring->size, rx_ring->desc, rx_ring->dma);
 
-       adapter->rx_ring.desc = NULL;
+       rx_ring->desc = NULL;
 }
 
 /**
@@ -1042,35 +1045,38 @@ e1000_free_rx_resources(struct e1000_adapter *adapter)
 static void
 e1000_clean_rx_ring(struct e1000_adapter *adapter)
 {
+       struct e1000_desc_ring *rx_ring = &adapter->rx_ring;
+       struct e1000_buffer *buffer_info;
        struct pci_dev *pdev = adapter->pdev;
        unsigned long size;
-       int i;
+       unsigned int i;
 
        /* Free all the Rx ring sk_buffs */
 
-       for(i = 0; i < adapter->rx_ring.count; i++) {
-               if(adapter->rx_ring.buffer_info[i].skb) {
+       for(i = 0; i < rx_ring->count; i++) {
+               buffer_info = &rx_ring->buffer_info[i];
+               if(buffer_info->skb) {
 
                        pci_unmap_single(pdev,
-                                        adapter->rx_ring.buffer_info[i].dma,
-                                        adapter->rx_ring.buffer_info[i].length,
+                                        buffer_info->dma,
+                                        buffer_info->length,
                                         PCI_DMA_FROMDEVICE);
 
-                       dev_kfree_skb(adapter->rx_ring.buffer_info[i].skb);
+                       dev_kfree_skb(buffer_info->skb);
 
-                       adapter->rx_ring.buffer_info[i].skb = NULL;
+                       buffer_info->skb = NULL;
                }
        }
 
-       size = sizeof(struct e1000_buffer) * adapter->rx_ring.count;
-       memset(adapter->rx_ring.buffer_info, 0, size);
+       size = sizeof(struct e1000_buffer) * rx_ring->count;
+       memset(rx_ring->buffer_info, 0, size);
 
        /* Zero out the descriptor ring */
 
-       memset(adapter->rx_ring.desc, 0, adapter->rx_ring.size);
+       memset(rx_ring->desc, 0, rx_ring->size);
 
-       adapter->rx_ring.next_to_clean = 0;
-       adapter->rx_ring.next_to_use = 0;
+       rx_ring->next_to_clean = 0;
+       rx_ring->next_to_use = 0;
 
        E1000_WRITE_REG(&adapter->hw, RDH, 0);
        E1000_WRITE_REG(&adapter->hw, RDT, 0);
@@ -1320,7 +1326,7 @@ e1000_watchdog(unsigned long data)
        struct e1000_adapter *adapter = (struct e1000_adapter *) data;
        struct net_device *netdev = adapter->netdev;
        struct e1000_desc_ring *txdr = &adapter->tx_ring;
-       int i;
+       unsigned int i;
 
        e1000_check_for_link(&adapter->hw);
 
@@ -1406,7 +1412,7 @@ e1000_tso(struct e1000_adapter *adapter, struct sk_buff *skb)
 {
 #ifdef NETIF_F_TSO
        struct e1000_context_desc *context_desc;
-       int i;
+       unsigned int i;
        uint8_t ipcss, ipcso, tucss, tucso, hdr_len;
        uint16_t ipcse, tucse, mss;
 
@@ -1457,7 +1463,7 @@ static inline boolean_t
 e1000_tx_csum(struct e1000_adapter *adapter, struct sk_buff *skb)
 {
        struct e1000_context_desc *context_desc;
-       int i;
+       unsigned int i;
        uint8_t css, cso;
 
        if(skb->ip_summed == CHECKSUM_HW) {
@@ -1490,18 +1496,21 @@ e1000_tx_map(struct e1000_adapter *adapter, struct sk_buff *skb,
        unsigned int first)
 {
        struct e1000_desc_ring *tx_ring = &adapter->tx_ring;
-       int len = skb->len, offset = 0, size, count = 0, i;
+       struct e1000_buffer *buffer_info;
+       int len = skb->len;
+       unsigned int offset = 0, size, count = 0, i;
 
 #ifdef NETIF_F_TSO
-       int tso = skb_shinfo(skb)->tso_size;
+       unsigned int tso = skb_shinfo(skb)->tso_size;
 #endif
-       int nr_frags = skb_shinfo(skb)->nr_frags;
-       int f;
+       unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
+       unsigned int f;
        len -= skb->data_len;
 
        i = tx_ring->next_to_use;
 
        while(len) {
+               buffer_info = &tx_ring->buffer_info[i];
                size = min(len, E1000_MAX_DATA_PER_TXD);
 #ifdef NETIF_F_TSO
                /* Workaround for premature desc write-backs
@@ -1509,13 +1518,13 @@ e1000_tx_map(struct e1000_adapter *adapter, struct sk_buff *skb,
                if(tso && !nr_frags && size == len && size > 4)
                        size -= 4;
 #endif
-               tx_ring->buffer_info[i].length = size;
-               tx_ring->buffer_info[i].dma =
+               buffer_info->length = size;
+               buffer_info->dma =
                        pci_map_single(adapter->pdev,
                                skb->data + offset,
                                size,
                                PCI_DMA_TODEVICE);
-               tx_ring->buffer_info[i].time_stamp = jiffies;
+               buffer_info->time_stamp = jiffies;
 
                len -= size;
                offset += size;
@@ -1531,6 +1540,7 @@ e1000_tx_map(struct e1000_adapter *adapter, struct sk_buff *skb,
                offset = 0;
 
                while(len) {
+                       buffer_info = &tx_ring->buffer_info[i];
                        size = min(len, E1000_MAX_DATA_PER_TXD);
 #ifdef NETIF_F_TSO
                        /* Workaround for premature desc write-backs
@@ -1538,14 +1548,14 @@ e1000_tx_map(struct e1000_adapter *adapter, struct sk_buff *skb,
                        if(tso && f == (nr_frags-1) && size == len && size > 4)
                                size -= 4;
 #endif
-                       tx_ring->buffer_info[i].length = size;
-                       tx_ring->buffer_info[i].dma =
+                       buffer_info->length = size;
+                       buffer_info->dma =
                                pci_map_page(adapter->pdev,
                                        frag->page,
                                        frag->page_offset + offset,
                                        size,
                                        PCI_DMA_TODEVICE);
-                       tx_ring->buffer_info[i].time_stamp = jiffies;
+                       buffer_info->time_stamp = jiffies;
 
                        len -= size;
                        offset += size;
@@ -1553,7 +1563,7 @@ e1000_tx_map(struct e1000_adapter *adapter, struct sk_buff *skb,
                        if(++i == tx_ring->count) i = 0;
                }
        }
-       if(--i < 0) i = tx_ring->count - 1;
+       i = (i == 0) ? tx_ring->count - 1 : i - 1;
        tx_ring->buffer_info[i].skb = skb;
        tx_ring->buffer_info[first].next_to_watch = i;
 
@@ -1565,8 +1575,9 @@ e1000_tx_queue(struct e1000_adapter *adapter, int count, int tx_flags)
 {
        struct e1000_desc_ring *tx_ring = &adapter->tx_ring;
        struct e1000_tx_desc *tx_desc = NULL;
+       struct e1000_buffer *buffer_info;
        uint32_t txd_upper = 0, txd_lower = E1000_TXD_CMD_IFCS;
-       int i;
+       unsigned int i;
 
        if(tx_flags & E1000_TX_FLAGS_TSO) {
                txd_lower |= E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D |
@@ -1587,10 +1598,11 @@ e1000_tx_queue(struct e1000_adapter *adapter, int count, int tx_flags)
        i = tx_ring->next_to_use;
 
        while(count--) {
+               buffer_info = &tx_ring->buffer_info[i];
                tx_desc = E1000_TX_DESC(*tx_ring, i);
-               tx_desc->buffer_addr = cpu_to_le64(tx_ring->buffer_info[i].dma);
+               tx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
                tx_desc->lower.data =
-                       cpu_to_le32(txd_lower | tx_ring->buffer_info[i].length);
+                       cpu_to_le32(txd_lower | buffer_info->length);
                tx_desc->upper.data = cpu_to_le32(txd_upper);
                if(++i == tx_ring->count) i = 0;
        }
@@ -1656,7 +1668,7 @@ e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
 {
        struct e1000_adapter *adapter = netdev->priv;
        unsigned int first;
-       int tx_flags = 0;
+       unsigned int tx_flags = 0;
 
        if(skb->len <= 0) {
                dev_kfree_skb_any(skb);
@@ -1968,7 +1980,7 @@ e1000_intr(int irq, void *data, struct pt_regs *regs)
        struct e1000_adapter *adapter = netdev->priv;
        uint32_t icr = E1000_READ_REG(&adapter->hw, ICR);
 #ifndef CONFIG_E1000_NAPI
-       int i;
+       unsigned int i;
 #endif
 
        if(!icr)
@@ -2040,7 +2052,8 @@ e1000_clean_tx_irq(struct e1000_adapter *adapter)
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_tx_desc *tx_desc, *eop_desc;
        struct e1000_buffer *buffer_info;
-       int i, eop, cleaned = FALSE;
+       unsigned int i, eop;
+       boolean_t cleaned = FALSE;
 
        i = tx_ring->next_to_clean;
        eop = tx_ring->buffer_info[i].next_to_watch;
@@ -2106,16 +2119,19 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter)
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_rx_desc *rx_desc;
+       struct e1000_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned long flags;
        uint32_t length;
        uint8_t last_byte;
-       int i, cleaned = FALSE;
+       unsigned int i;
+       boolean_t cleaned = FALSE;
 
        i = rx_ring->next_to_clean;
        rx_desc = E1000_RX_DESC(*rx_ring, i);
 
        while(rx_desc->status & E1000_RXD_STAT_DD) {
+               buffer_info = &rx_ring->buffer_info[i];
 
 #ifdef CONFIG_E1000_NAPI
                if(*work_done >= work_to_do)
@@ -2127,11 +2143,11 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter)
                cleaned = TRUE;
 
                pci_unmap_single(pdev,
-                                rx_ring->buffer_info[i].dma,
-                                rx_ring->buffer_info[i].length,
+                                buffer_info->dma,
+                                buffer_info->length,
                                 PCI_DMA_FROMDEVICE);
 
-               skb = rx_ring->buffer_info[i].skb;
+               skb = buffer_info->skb;
                length = le16_to_cpu(rx_desc->length);
 
                if(!(rx_desc->status & E1000_RXD_STAT_EOP)) {
@@ -2142,7 +2158,7 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter)
 
                        dev_kfree_skb_irq(skb);
                        rx_desc->status = 0;
-                       rx_ring->buffer_info[i].skb = NULL;
+                       buffer_info->skb = NULL;
 
                        if(++i == rx_ring->count) i = 0;
 
@@ -2170,7 +2186,7 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter)
 
                                dev_kfree_skb_irq(skb);
                                rx_desc->status = 0;
-                               rx_ring->buffer_info[i].skb = NULL;
+                               buffer_info->skb = NULL;
 
                                if(++i == rx_ring->count) i = 0;
 
@@ -2206,7 +2222,7 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter)
                netdev->last_rx = jiffies;
 
                rx_desc->status = 0;
-               rx_ring->buffer_info[i].skb = NULL;
+               buffer_info->skb = NULL;
 
                if(++i == rx_ring->count) i = 0;
 
@@ -2232,13 +2248,15 @@ e1000_alloc_rx_buffers(struct e1000_adapter *adapter)
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_rx_desc *rx_desc;
+       struct e1000_buffer *buffer_info;
        struct sk_buff *skb;
        int reserve_len = 2;
-       int i;
+       unsigned int i;
 
        i = rx_ring->next_to_use;
+       buffer_info = &rx_ring->buffer_info[i];
 
-       while(!rx_ring->buffer_info[i].skb) {
+       while(!buffer_info->skb) {
                rx_desc = E1000_RX_DESC(*rx_ring, i);
 
                skb = dev_alloc_skb(adapter->rx_buffer_len + reserve_len);
@@ -2256,15 +2274,15 @@ e1000_alloc_rx_buffers(struct e1000_adapter *adapter)
 
                skb->dev = netdev;
 
-               rx_ring->buffer_info[i].skb = skb;
-               rx_ring->buffer_info[i].length = adapter->rx_buffer_len;
-               rx_ring->buffer_info[i].dma =
+               buffer_info->skb = skb;
+               buffer_info->length = adapter->rx_buffer_len;
+               buffer_info->dma =
                        pci_map_single(pdev,
                                       skb->data,
                                       adapter->rx_buffer_len,
                                       PCI_DMA_FROMDEVICE);
 
-               rx_desc->buffer_addr = cpu_to_le64(rx_ring->buffer_info[i].dma);
+               rx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
 
                if((i & ~(E1000_RX_BUFFER_WRITE - 1)) == i) {
                        /* Force memory writes to complete before letting h/w
@@ -2277,6 +2295,7 @@ e1000_alloc_rx_buffers(struct e1000_adapter *adapter)
                }
 
                if(++i == rx_ring->count) i = 0;
+               buffer_info = &rx_ring->buffer_info[i];
        }
 
        rx_ring->next_to_use = i;