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Merge branch 'dma_rmb_wmb'

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Alexander Duyck says:

====================
Replace wmb()/rmb() with dma_wmb()/dma_rmb() where appropriate

This is a start of a side project cleaning up the drivers that can make use
of the dma_wmb and dma_rmb calls.  The general idea is to start removing
the unnecessary wmb/rmb calls from a number of drivers and to make use of
the lighter weight dma_wmb/dma_rmb calls as this should allow for an
overall improvement in performance as each barrier can cost a significant
number of cycles and on architectures such as x86 this is unnecessary.

These changes are what I would consider low hanging fruit.  The likelihood
of the changes introducing an error should be low since the use of the
barriers in these cases are fairly obvious.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2015-04-08 12:15:15 -04:00
commit b5de97bc17
6 changed files with 29 additions and 29 deletions
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6
drivers/net/ethernet/intel/e1000/e1000_main.c
View File

@ -3856,7 +3856,7 @@ static bool e1000_clean_tx_irq(struct e1000_adapter *adapter,
while ((eop_desc->upper.data & cpu_to_le32(E1000_TXD_STAT_DD)) &&
(count < tx_ring->count)) {
bool cleaned = false;
rmb(); /* read buffer_info after eop_desc */
dma_rmb(); /* read buffer_info after eop_desc */
for ( ; !cleaned; count++) {
tx_desc = E1000_TX_DESC(*tx_ring, i);
buffer_info = &tx_ring->buffer_info[i];
@ -4154,7 +4154,7 @@ static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
if (*work_done >= work_to_do)
break;
(*work_done)++;
rmb(); /* read descriptor and rx_buffer_info after status DD */
dma_rmb(); /* read descriptor and rx_buffer_info after status DD */
status = rx_desc->status;
@ -4375,7 +4375,7 @@ static bool e1000_clean_rx_irq(struct e1000_adapter *adapter,
if (*work_done >= work_to_do)
break;
(*work_done)++;
rmb(); /* read descriptor and rx_buffer_info after status DD */
dma_rmb(); /* read descriptor and rx_buffer_info after status DD */
status = rx_desc->status;
length = le16_to_cpu(rx_desc->length);

8
drivers/net/ethernet/intel/e1000e/netdev.c
View File

@ -947,7 +947,7 @@ static bool e1000_clean_rx_irq(struct e1000_ring *rx_ring, int *work_done,
if (*work_done >= work_to_do)
break;
(*work_done)++;
rmb(); /* read descriptor and rx_buffer_info after status DD */
dma_rmb(); /* read descriptor and rx_buffer_info after status DD */
skb = buffer_info->skb;
buffer_info->skb = NULL;
@ -1232,7 +1232,7 @@ static bool e1000_clean_tx_irq(struct e1000_ring *tx_ring)
(count < tx_ring->count)) {
bool cleaned = false;
rmb(); /* read buffer_info after eop_desc */
dma_rmb(); /* read buffer_info after eop_desc */
for (; !cleaned; count++) {
tx_desc = E1000_TX_DESC(*tx_ring, i);
buffer_info = &tx_ring->buffer_info[i];
@ -1332,7 +1332,7 @@ static bool e1000_clean_rx_irq_ps(struct e1000_ring *rx_ring, int *work_done,
break;
(*work_done)++;
skb = buffer_info->skb;
rmb(); /* read descriptor and rx_buffer_info after status DD */
dma_rmb(); /* read descriptor and rx_buffer_info after status DD */
/* in the packet split case this is header only */
prefetch(skb->data - NET_IP_ALIGN);
@ -1536,7 +1536,7 @@ static bool e1000_clean_jumbo_rx_irq(struct e1000_ring *rx_ring, int *work_done,
if (*work_done >= work_to_do)
break;
(*work_done)++;
rmb(); /* read descriptor and rx_buffer_info after status DD */
dma_rmb(); /* read descriptor and rx_buffer_info after status DD */
skb = buffer_info->skb;
buffer_info->skb = NULL;

8
drivers/net/ethernet/neterion/s2io.c
View File

@ -2520,7 +2520,7 @@ static int fill_rx_buffers(struct s2io_nic *nic, struct ring_info *ring,
DBG_PRINT(INFO_DBG, "%s: Could not allocate skb\n",
ring->dev->name);
if (first_rxdp) {
wmb();
dma_wmb();
first_rxdp->Control_1 |= RXD_OWN_XENA;
}
swstats->mem_alloc_fail_cnt++;
@ -2634,7 +2634,7 @@ static int fill_rx_buffers(struct s2io_nic *nic, struct ring_info *ring,
rxdp->Control_2 |= SET_RXD_MARKER;
if (!(alloc_tab & ((1 << rxsync_frequency) - 1))) {
if (first_rxdp) {
wmb();
dma_wmb();
first_rxdp->Control_1 |= RXD_OWN_XENA;
}
first_rxdp = rxdp;
@ -2649,7 +2649,7 @@ end:
* and other fields are seen by adapter correctly.
*/
if (first_rxdp) {
wmb();
dma_wmb();
first_rxdp->Control_1 |= RXD_OWN_XENA;
}
@ -6950,7 +6950,7 @@ static int rxd_owner_bit_reset(struct s2io_nic *sp)
}
set_rxd_buffer_size(sp, rxdp, size);
wmb();
dma_wmb();
/* flip the Ownership bit to Hardware */
rxdp->Control_1 |= RXD_OWN_XENA;
}

14
drivers/net/ethernet/sun/sungem.c
View File

@ -718,7 +718,7 @@ static __inline__ void gem_post_rxds(struct gem *gp, int limit)
cluster_start = curr = (gp->rx_new & ~(4 - 1));
count = 0;
kick = -1;
wmb();
dma_wmb();
while (curr != limit) {
curr = NEXT_RX(curr);
if (++count == 4) {
@ -1038,7 +1038,7 @@ static netdev_tx_t gem_start_xmit(struct sk_buff *skb,
if (gem_intme(entry))
ctrl |= TXDCTRL_INTME;
txd->buffer = cpu_to_le64(mapping);
wmb();
dma_wmb();
txd->control_word = cpu_to_le64(ctrl);
entry = NEXT_TX(entry);
} else {
@ -1076,7 +1076,7 @@ static netdev_tx_t gem_start_xmit(struct sk_buff *skb,
txd = &gp->init_block->txd[entry];
txd->buffer = cpu_to_le64(mapping);
wmb();
dma_wmb();
txd->control_word = cpu_to_le64(this_ctrl | len);
if (gem_intme(entry))
@ -1086,7 +1086,7 @@ static netdev_tx_t gem_start_xmit(struct sk_buff *skb,
}
txd = &gp->init_block->txd[first_entry];
txd->buffer = cpu_to_le64(first_mapping);
wmb();
dma_wmb();
txd->control_word =
cpu_to_le64(ctrl | TXDCTRL_SOF | intme | first_len);
}
@ -1585,7 +1585,7 @@ static void gem_clean_rings(struct gem *gp)
gp->rx_skbs[i] = NULL;
}
rxd->status_word = 0;
wmb();
dma_wmb();
rxd->buffer = 0;
}
@ -1647,7 +1647,7 @@ static void gem_init_rings(struct gem *gp)
RX_BUF_ALLOC_SIZE(gp),
PCI_DMA_FROMDEVICE);
rxd->buffer = cpu_to_le64(dma_addr);
wmb();
dma_wmb();
rxd->status_word = cpu_to_le64(RXDCTRL_FRESH(gp));
skb_reserve(skb, RX_OFFSET);
}
@ -1656,7 +1656,7 @@ static void gem_init_rings(struct gem *gp)
struct gem_txd *txd = &gb->txd[i];
txd->control_word = 0;
wmb();
dma_wmb();
txd->buffer = 0;
}
wmb();

16
drivers/net/ethernet/sun/sunhme.c
View File

@ -196,14 +196,14 @@ static u32 sbus_hme_read32(void __iomem *reg)
static void sbus_hme_write_rxd(struct happy_meal_rxd *rxd, u32 flags, u32 addr)
{
rxd->rx_addr = (__force hme32)addr;
wmb();
dma_wmb();
rxd->rx_flags = (__force hme32)flags;
}
static void sbus_hme_write_txd(struct happy_meal_txd *txd, u32 flags, u32 addr)
{
txd->tx_addr = (__force hme32)addr;
wmb();
dma_wmb();
txd->tx_flags = (__force hme32)flags;
}
@ -225,14 +225,14 @@ static u32 pci_hme_read32(void __iomem *reg)
static void pci_hme_write_rxd(struct happy_meal_rxd *rxd, u32 flags, u32 addr)
{
rxd->rx_addr = (__force hme32)cpu_to_le32(addr);
wmb();
dma_wmb();
rxd->rx_flags = (__force hme32)cpu_to_le32(flags);
}
static void pci_hme_write_txd(struct happy_meal_txd *txd, u32 flags, u32 addr)
{
txd->tx_addr = (__force hme32)cpu_to_le32(addr);
wmb();
dma_wmb();
txd->tx_flags = (__force hme32)cpu_to_le32(flags);
}
@ -268,12 +268,12 @@ static u32 pci_hme_read_desc32(hme32 *p)
sbus_readl(__reg)
#define hme_write_rxd(__hp, __rxd, __flags, __addr) \
do { (__rxd)->rx_addr = (__force hme32)(u32)(__addr); \
wmb(); \
dma_wmb(); \
(__rxd)->rx_flags = (__force hme32)(u32)(__flags); \
} while(0)
#define hme_write_txd(__hp, __txd, __flags, __addr) \
do { (__txd)->tx_addr = (__force hme32)(u32)(__addr); \
wmb(); \
dma_wmb(); \
(__txd)->tx_flags = (__force hme32)(u32)(__flags); \
} while(0)
#define hme_read_desc32(__hp, __p) ((__force u32)(hme32)*(__p))
@ -293,12 +293,12 @@ do { (__txd)->tx_addr = (__force hme32)(u32)(__addr); \
readl(__reg)
#define hme_write_rxd(__hp, __rxd, __flags, __addr) \
do { (__rxd)->rx_addr = (__force hme32)cpu_to_le32(__addr); \
wmb(); \
dma_wmb(); \
(__rxd)->rx_flags = (__force hme32)cpu_to_le32(__flags); \
} while(0)
#define hme_write_txd(__hp, __txd, __flags, __addr) \
do { (__txd)->tx_addr = (__force hme32)cpu_to_le32(__addr); \
wmb(); \
dma_wmb(); \
(__txd)->tx_flags = (__force hme32)cpu_to_le32(__flags); \
} while(0)
static inline u32 hme_read_desc32(struct happy_meal *hp, hme32 *p)

6
drivers/net/ethernet/sun/sunvnet.c
View File

@ -519,7 +519,7 @@ static int vnet_walk_rx_one(struct vnet_port *port,
if (desc->hdr.state != VIO_DESC_READY)
return 1;
rmb();
dma_rmb();
viodbg(DATA, "vio_walk_rx_one desc[%02x:%02x:%08x:%08x:%llx:%llx]\n",
desc->hdr.state, desc->hdr.ack,
@ -1380,7 +1380,7 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
/* This has to be a non-SMP write barrier because we are writing
* to memory which is shared with the peer LDOM.
*/
wmb();
dma_wmb();
d->hdr.state = VIO_DESC_READY;
@ -1395,7 +1395,7 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
* is marked READY, but start_cons was false.
* If so, vnet_ack() should send out the missed "start" trigger.
*
* Note that the wmb() above makes sure the cookies et al. are
* Note that the dma_wmb() above makes sure the cookies et al. are
* not globally visible before the VIO_DESC_READY, and that the
* stores are ordered correctly by the compiler. The consumer will
* not proceed until the VIO_DESC_READY is visible assuring that