Auke,
heres part of something i promised.
I couldnt do any packet testing on because 82571EB is disabled in the
driver. I uncommented the code out in the table, but the best i could
get was the module loading, some probing and some sysfs renaming
failures (probably a debianism); the machine access is intermittent, so
thats as far as i could go. In any case, you probably have a good reason
for disabling that chip. So, heres the patch, the burden of testing now
falls on you ;->
Once you have 82571EB on and kicking, my next steps are to kill LLTX
then add batching on top.
BTW, since this driver is just for PCIE, would you take a similar patch
for non-PCIE e1000?
comment:
There used to be an "mmiowb()" call right after the dma wake which is
gone now; is this unneeded with pcie? I have restored it, look for the
"XXX".
cheers,
jamal
[E1000E] some cleanups
This patch makes the xmit path code a lot more readable and reusable.
preps for removing LLTX.
Signed-off-by: Jamal Hadi Salim <[EMAIL PROTECTED]>
---
commit ad63c288ce980907f68d94d5faac08625c0b1782
tree 296a6da371b98c6488c544a8910941ea6d8c18a8
parent 7f5d0afdff875b2c4957031f8934741aefe257cc
author Jamal Hadi Salim <[EMAIL PROTECTED]> Sun, 30 Sep 2007 13:26:00 -0400
committer Jamal Hadi Salim <[EMAIL PROTECTED]> Sun, 30 Sep 2007 13:26:00 -0400
drivers/net/e1000e/netdev.c | 187 +++++++++++++++++++++++++++----------------
1 files changed, 119 insertions(+), 68 deletions(-)
diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 4a21d7d..5043504 100644
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -3076,6 +3076,18 @@ link_up:
#define E1000_TX_FLAGS_VLAN_MASK 0xffff0000
#define E1000_TX_FLAGS_VLAN_SHIFT 16
+struct e1000_tx_cbdata {
+ int count;
+ unsigned int max_per_txd;
+ unsigned int nr_frags;
+ unsigned int mss;
+ unsigned int tx_flags;
+};
+
+#define E1000_SKB_CB(__skb) ((struct e1000_tx_cbdata *)&((__skb)->cb[8]))
+#define NETDEV_TX_DROPPED -5
+#define TXD_USE_COUNT(S, X) (((S) >> (X)) + 1)
+
static int e1000_tso(struct e1000_adapter *adapter,
struct sk_buff *skb)
{
@@ -3194,8 +3206,7 @@ static bool e1000_tx_csum(struct e1000_adapter *adapter,
struct sk_buff *skb)
static int e1000_tx_map(struct e1000_adapter *adapter,
struct sk_buff *skb, unsigned int first,
- unsigned int max_per_txd, unsigned int nr_frags,
- unsigned int mss)
+ struct e1000_tx_cbdata *cb)
{
struct e1000_ring *tx_ring = adapter->tx_ring;
struct e1000_buffer *buffer_info;
@@ -3207,11 +3218,11 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
while (len) {
buffer_info = &tx_ring->buffer_info[i];
- size = min(len, max_per_txd);
+ size = min(len, cb->max_per_txd);
/* Workaround for premature desc write-backs
* in TSO mode. Append 4-byte sentinel desc */
- if (mss && !nr_frags && size == len && size > 8)
+ if (cb->mss && !cb->nr_frags && size == len && size > 8)
size -= 4;
buffer_info->length = size;
@@ -3237,7 +3248,7 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
i = 0;
}
- for (f = 0; f < nr_frags; f++) {
+ for (f = 0; f < cb->nr_frags; f++) {
struct skb_frag_struct *frag;
frag = &skb_shinfo(skb)->frags[f];
@@ -3246,10 +3257,11 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
while (len) {
buffer_info = &tx_ring->buffer_info[i];
- size = min(len, max_per_txd);
+ size = min(len, cb->max_per_txd);
/* Workaround for premature desc write-backs
* in TSO mode. Append 4-byte sentinel desc */
- if (mss && f == (nr_frags-1) && size == len && size > 8)
+ if (cb->mss && f == (cb->nr_frags-1) &&
+ size == len && size > 8)
size -= 4;
buffer_info->length = size;
@@ -3334,18 +3346,7 @@ static void e1000_tx_queue(struct e1000_adapter *adapter,
}
tx_desc->lower.data |= cpu_to_le32(adapter->txd_cmd);
-
- /* Force memory writes to complete before letting h/w
- * know there are new descriptors to fetch. (Only
- * applicable for weak-ordered memory model archs,
- * such as IA-64). */
- wmb();
-
tx_ring->next_to_use = i;
- writel(i, adapter->hw.hw_addr + tx_ring->tail);
- /* we need this if more than one processor can write to our tail
- * at a time, it synchronizes IO on IA64/Altix systems */
- mmiowb();
}
#define MINIMUM_DHCP_PACKET_SIZE 282
@@ -3417,45 +3418,54 @@ static int e1000_maybe_stop_tx(struct net_device
*netdev, int size)
return __e1000_maybe_stop_tx(netdev, size);
}
-#define TXD_USE_COUNT(S, X) (((S) >> (X)) + 1 )
-static int e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
+static void
+e1000_complete_tx(struct net_device *netdev)
{
struct e1000_adapter *adapter = netdev_priv(netdev);
struct e1000_ring *tx_ring = adapter->tx_ring;
- unsigned int first;
- unsigned int max_per_txd = E1000_MAX_PER_TXD;
+ /* Force memory writes to complete before letting h/w
+ * know there are new descriptors to fetch. (Only
+ * applicable for weak-ordered memory model archs,
+ * such as IA-64). */
+ wmb();
+ writel(tx_ring->next_to_use, adapter->hw.hw_addr + tx_ring->tail);
+ /* XXX: we need this if more than one processor can write to
+ * our tail at a time, it syncronizes IO on IA64/Altix systems */
+ mmiowb();
+ netdev->trans_start = jiffies;
+}
+
+static int e1000_prep_frame(struct sk_buff *skb, struct net_device *netdev)
+{
+ struct e1000_adapter *adapter = netdev_priv(netdev);
unsigned int max_txd_pwr = E1000_MAX_TXD_PWR;
- unsigned int tx_flags = 0;
unsigned int len = skb->len;
- unsigned long irq_flags;
- unsigned int nr_frags = 0;
- unsigned int mss = 0;
- int count = 0;
- int tso;
+ struct e1000_tx_cbdata *cb = E1000_SKB_CB(skb);
unsigned int f;
- len -= skb->data_len;
- if (test_bit(__E1000_DOWN, &adapter->state)) {
- dev_kfree_skb_any(skb);
- return NETDEV_TX_OK;
- }
+ cb->nr_frags = 0;
+ cb->mss = 0;
+ cb->count = 0;
+ cb->max_per_txd = E1000_MAX_PER_TXD;
+
+ len -= skb->data_len;
if (skb->len <= 0) {
dev_kfree_skb_any(skb);
- return NETDEV_TX_OK;
+ return NETDEV_TX_DROPPED;
}
- mss = skb_shinfo(skb)->gso_size;
+ cb->mss = skb_shinfo(skb)->gso_size;
/* The controller does a simple calculation to
* make sure there is enough room in the FIFO before
* initiating the DMA for each buffer. The calc is:
* 4 = ceil(buffer len/mss). To make sure we don't
* overrun the FIFO, adjust the max buffer len if mss
* drops. */
- if (mss) {
+ if (cb->mss) {
u8 hdr_len;
- max_per_txd = min(mss << 2, max_per_txd);
- max_txd_pwr = fls(max_per_txd) - 1;
+ cb->max_per_txd = min(cb->mss << 2, cb->max_per_txd);
+ max_txd_pwr = fls(cb->max_per_txd) - 1;
/* TSO Workaround for 82571/2/3 Controllers -- if skb->data
* points to just header, pull a few bytes of payload from
@@ -3469,80 +3479,121 @@ static int e1000_xmit_frame(struct sk_buff *skb,
struct net_device *netdev)
ndev_err(netdev,
"__pskb_pull_tail failed.\n");
dev_kfree_skb_any(skb);
- return NETDEV_TX_OK;
+ return NETDEV_TX_DROPPED;
}
len = skb->len - skb->data_len;
}
}
/* reserve a descriptor for the offload context */
- if ((mss) || (skb->ip_summed == CHECKSUM_PARTIAL))
- count++;
- count++;
+ if ((cb->mss) || (skb->ip_summed == CHECKSUM_PARTIAL))
+ cb->count++;
+ cb->count++;
- count += TXD_USE_COUNT(len, max_txd_pwr);
+ cb->count += TXD_USE_COUNT(len, max_txd_pwr);
- nr_frags = skb_shinfo(skb)->nr_frags;
- for (f = 0; f < nr_frags; f++)
- count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size,
+ cb->nr_frags = skb_shinfo(skb)->nr_frags;
+ for (f = 0; f < cb->nr_frags; f++)
+ cb->count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size,
max_txd_pwr);
if (adapter->hw.mac.tx_pkt_filtering)
e1000_transfer_dhcp_info(adapter, skb);
- if (!spin_trylock_irqsave(&adapter->tx_queue_lock, irq_flags))
- /* Collision - tell upper layer to requeue */
- return NETDEV_TX_LOCKED;
+ if (adapter->vlgrp && vlan_tx_tag_present(skb)) {
+ cb->tx_flags |= E1000_TX_FLAGS_VLAN;
+ cb->tx_flags |= (vlan_tx_tag_get(skb) <<
+ E1000_TX_FLAGS_VLAN_SHIFT);
+ }
+
+ return NETDEV_TX_OK;
+}
+
+static int e1000_queue_frame(struct sk_buff *skb, struct net_device *netdev)
+{
+ struct e1000_adapter *adapter = netdev_priv(netdev);
+ struct e1000_ring *tx_ring = adapter->tx_ring;
+ unsigned int first;
+ int tso;
+ struct e1000_tx_cbdata *cb = E1000_SKB_CB(skb);
+
/* need: count + 2 desc gap to keep tail from touching
* head, otherwise try next time */
- if (e1000_maybe_stop_tx(netdev, count + 2)) {
- spin_unlock_irqrestore(&adapter->tx_queue_lock, irq_flags);
+ if (e1000_maybe_stop_tx(netdev, cb->count + 2))
return NETDEV_TX_BUSY;
- }
-
- if (adapter->vlgrp && vlan_tx_tag_present(skb)) {
- tx_flags |= E1000_TX_FLAGS_VLAN;
- tx_flags |= (vlan_tx_tag_get(skb) << E1000_TX_FLAGS_VLAN_SHIFT);
- }
first = tx_ring->next_to_use;
tso = e1000_tso(adapter, skb);
if (tso < 0) {
dev_kfree_skb_any(skb);
- spin_unlock_irqrestore(&adapter->tx_queue_lock, irq_flags);
- return NETDEV_TX_OK;
+ return NETDEV_TX_DROPPED;
}
if (tso)
- tx_flags |= E1000_TX_FLAGS_TSO;
+ cb->tx_flags |= E1000_TX_FLAGS_TSO;
else if (e1000_tx_csum(adapter, skb))
- tx_flags |= E1000_TX_FLAGS_CSUM;
+ cb->tx_flags |= E1000_TX_FLAGS_CSUM;
/* Old method was to assume IPv4 packet by default if TSO was enabled.
* 82571 hardware supports TSO capabilities for IPv6 as well...
* no longer assume, we must. */
if (skb->protocol == htons(ETH_P_IP))
- tx_flags |= E1000_TX_FLAGS_IPV4;
+ cb->tx_flags |= E1000_TX_FLAGS_IPV4;
- count = e1000_tx_map(adapter, skb, first, max_per_txd, nr_frags, mss);
- if (count < 0) {
+ cb->count = e1000_tx_map(adapter, skb, first, cb);
+ if (cb->count < 0) {
/* handle pci_map_single() error in e1000_tx_map */
dev_kfree_skb_any(skb);
- spin_unlock_irqrestore(&adapter->tx_queue_lock, irq_flags);
+ return NETDEV_TX_DROPPED;
+ }
+
+ e1000_tx_queue(adapter, cb->tx_flags, cb->count);
+
+ return NETDEV_TX_OK;
+}
+
+static int e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
+{
+ int ret = NETDEV_TX_OK;
+ struct e1000_adapter *adapter = netdev_priv(netdev);
+ unsigned long irq_flags;
+ struct e1000_tx_cbdata *cb = E1000_SKB_CB(skb);
+
+ ret = e1000_prep_frame(skb, netdev);
+ if (unlikely(ret != NETDEV_TX_OK))
+ return NETDEV_TX_OK;
+
+ if (test_bit(__E1000_DOWN, &adapter->state)) {
+ dev_kfree_skb_any(skb);
return NETDEV_TX_OK;
}
- e1000_tx_queue(adapter, tx_flags, count);
+ if (!spin_trylock_irqsave(&adapter->tx_queue_lock, irq_flags))
+ /* Collision - tell upper layer to requeue */
+ return NETDEV_TX_LOCKED;
- netdev->trans_start = jiffies;
+ /* need: count + 2 desc gap to keep tail from touching
+ * head, otherwise try next time */
+ if (e1000_maybe_stop_tx(netdev, cb->count + 2)) {
+ spin_unlock_irqrestore(&adapter->tx_queue_lock, irq_flags);
+ return NETDEV_TX_BUSY;
+ }
+
+ ret = e1000_queue_frame(skb, netdev);
+
+ if (ret == NETDEV_TX_OK)
+ e1000_complete_tx(netdev);
+
+ if (ret == NETDEV_TX_DROPPED)
+ ret = NETDEV_TX_OK;
/* Make sure there is space in the ring for the next send. */
e1000_maybe_stop_tx(netdev, MAX_SKB_FRAGS + 2);
spin_unlock_irqrestore(&adapter->tx_queue_lock, irq_flags);
- return NETDEV_TX_OK;
+ return ret;
}
/**
