tilepro ethernet driver: fix a few minor issues
This commit fixes a number of issues seen with the driver:
- Improve handling of return credits to the hardware shim
- Use skb_frag_size() appropriately
- Fix driver so it works properly with netpoll for console over UDP
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/drivers/net/ethernet/tile/tilepro.c b/drivers/net/ethernet/tile/tilepro.c
index 261356c..75e5905 100644
--- a/drivers/net/ethernet/tile/tilepro.c
+++ b/drivers/net/ethernet/tile/tilepro.c
@@ -342,6 +342,21 @@
}
+static void tile_net_return_credit(struct tile_net_cpu *info)
+{
+ struct tile_netio_queue *queue = &info->queue;
+ netio_queue_user_impl_t *qup = &queue->__user_part;
+
+ /* Return four credits after every fourth packet. */
+ if (--qup->__receive_credit_remaining == 0) {
+ u32 interval = qup->__receive_credit_interval;
+ qup->__receive_credit_remaining = interval;
+ __netio_fastio_return_credits(qup->__fastio_index, interval);
+ }
+}
+
+
+
/*
* Provide a linux buffer to LIPP.
*/
@@ -864,19 +879,11 @@
stats->rx_packets++;
stats->rx_bytes += len;
-
- if (small)
- info->num_needed_small_buffers++;
- else
- info->num_needed_large_buffers++;
}
- /* Return four credits after every fourth packet. */
- if (--qup->__receive_credit_remaining == 0) {
- u32 interval = qup->__receive_credit_interval;
- qup->__receive_credit_remaining = interval;
- __netio_fastio_return_credits(qup->__fastio_index, interval);
- }
+ /* ISSUE: It would be nice to defer this until the packet has */
+ /* actually been processed. */
+ tile_net_return_credit(info);
/* Consume this packet. */
qup->__packet_receive_read = index2;
@@ -1543,7 +1550,7 @@
/* Drain all the LIPP buffers. */
while (true) {
- int buffer;
+ unsigned int buffer;
/* NOTE: This should never fail. */
if (hv_dev_pread(priv->hv_devhdl, 0, (HV_VirtAddr)&buffer,
@@ -1707,7 +1714,7 @@
if (!hash_default) {
void *va = pfn_to_kaddr(pfn) + f->page_offset;
BUG_ON(PageHighMem(skb_frag_page(f)));
- finv_buffer_remote(va, f->size, 0);
+ finv_buffer_remote(va, skb_frag_size(f), 0);
}
cpa = ((phys_addr_t)pfn << PAGE_SHIFT) + f->page_offset;
@@ -1735,8 +1742,8 @@
* Sometimes, if "sendfile()" requires copying, we will be called with
* "data" containing the header and payload, with "frags" being empty.
*
- * In theory, "sh->nr_frags" could be 3, but in practice, it seems
- * that this will never actually happen.
+ * Sometimes, for example when using NFS over TCP, a single segment can
+ * span 3 fragments, which must be handled carefully in LEPP.
*
* See "emulate_large_send_offload()" for some reference code, which
* does not handle checksumming.
@@ -1844,10 +1851,8 @@
spin_lock_irqsave(&priv->eq_lock, irqflags);
- /*
- * Handle completions if needed to make room.
- * HACK: Spin until there is sufficient room.
- */
+ /* Handle completions if needed to make room. */
+ /* NOTE: Return NETDEV_TX_BUSY if there is still no room. */
if (lepp_num_free_comp_slots(eq) == 0) {
nolds = tile_net_lepp_grab_comps(eq, olds, wanted, 0);
if (nolds == 0) {
@@ -1861,6 +1866,7 @@
cmd_tail = eq->cmd_tail;
/* Prepare to advance, detecting full queue. */
+ /* NOTE: Return NETDEV_TX_BUSY if the queue is full. */
cmd_next = cmd_tail + cmd_size;
if (cmd_tail < cmd_head && cmd_next >= cmd_head)
goto busy;
@@ -2023,10 +2029,8 @@
spin_lock_irqsave(&priv->eq_lock, irqflags);
- /*
- * Handle completions if needed to make room.
- * HACK: Spin until there is sufficient room.
- */
+ /* Handle completions if needed to make room. */
+ /* NOTE: Return NETDEV_TX_BUSY if there is still no room. */
if (lepp_num_free_comp_slots(eq) == 0) {
nolds = tile_net_lepp_grab_comps(eq, olds, wanted, 0);
if (nolds == 0) {
@@ -2040,6 +2044,7 @@
cmd_tail = eq->cmd_tail;
/* Copy the commands, or fail. */
+ /* NOTE: Return NETDEV_TX_BUSY if the queue is full. */
for (i = 0; i < num_frags; i++) {
/* Prepare to advance, detecting full queue. */
@@ -2261,6 +2266,23 @@
return 0;
}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/*
+ * Polling 'interrupt' - used by things like netconsole to send skbs
+ * without having to re-enable interrupts. It's not called while
+ * the interrupt routine is executing.
+ */
+static void tile_net_netpoll(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+ disable_percpu_irq(priv->intr_id);
+ tile_net_handle_ingress_interrupt(priv->intr_id, dev);
+ enable_percpu_irq(priv->intr_id, 0);
+}
+#endif
+
+
static const struct net_device_ops tile_net_ops = {
.ndo_open = tile_net_open,
.ndo_stop = tile_net_stop,
@@ -2269,7 +2291,10 @@
.ndo_get_stats = tile_net_get_stats,
.ndo_change_mtu = tile_net_change_mtu,
.ndo_tx_timeout = tile_net_tx_timeout,
- .ndo_set_mac_address = tile_net_set_mac_address
+ .ndo_set_mac_address = tile_net_set_mac_address,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+ .ndo_poll_controller = tile_net_netpoll,
+#endif
};
@@ -2409,7 +2434,7 @@
*/
static int tile_net_init_module(void)
{
- pr_info("Tilera IPP Net Driver\n");
+ pr_info("Tilera Network Driver\n");
tile_net_devs[0] = tile_net_dev_init("xgbe0");
tile_net_devs[1] = tile_net_dev_init("xgbe1");