sfc: Split MAC stats DMA initiation and completion
From: Steve Hodgson <shodgson@solarflare.com>
Currently we initiate MAC stats DMA and busy-wait for completion when
stats are requested. We can improve on this with a periodic timer to
initiate and poll for stats, and opportunistically poll when stats are
requested.
Since efx_nic::stats_disable_count and efx_stats_{disable,enable}()
are Falcon-specific, rename them and move them accordingly.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index 155aa1c..41ca5db 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -637,6 +637,7 @@
netif_addr_unlock_bh(efx->net_dev);
}
+ falcon_stop_nic_stats(efx);
falcon_deconfigure_mac_wrapper(efx);
/* Reconfigure the PHY, disabling transmit in mac level loopback. */
@@ -651,6 +652,8 @@
efx->mac_op->reconfigure(efx);
+ falcon_start_nic_stats(efx);
+
/* Inform kernel of loss/gain of carrier */
efx_link_status_changed(efx);
return;
@@ -749,7 +752,6 @@
efx->mac_op->reconfigure(efx);
efx->port_initialized = true;
- efx_stats_enable(efx);
mutex_unlock(&efx->mac_lock);
return 0;
@@ -802,7 +804,6 @@
if (!efx->port_initialized)
return;
- efx_stats_disable(efx);
efx->phy_op->fini(efx);
efx->port_initialized = false;
@@ -1158,6 +1159,8 @@
if (efx->state == STATE_RUNNING)
queue_delayed_work(efx->workqueue, &efx->monitor_work,
efx_monitor_interval);
+
+ falcon_start_nic_stats(efx);
}
/* Flush all delayed work. Should only be called when no more delayed work
@@ -1195,6 +1198,8 @@
if (!efx->port_enabled)
return;
+ falcon_stop_nic_stats(efx);
+
/* Disable interrupts and wait for ISR to complete */
falcon_disable_interrupts(efx);
if (efx->legacy_irq)
@@ -1438,20 +1443,6 @@
return 0;
}
-void efx_stats_disable(struct efx_nic *efx)
-{
- spin_lock(&efx->stats_lock);
- ++efx->stats_disable_count;
- spin_unlock(&efx->stats_lock);
-}
-
-void efx_stats_enable(struct efx_nic *efx)
-{
- spin_lock(&efx->stats_lock);
- --efx->stats_disable_count;
- spin_unlock(&efx->stats_lock);
-}
-
/* Context: process, dev_base_lock or RTNL held, non-blocking. */
static struct net_device_stats *efx_net_stats(struct net_device *net_dev)
{
@@ -1459,17 +1450,9 @@
struct efx_mac_stats *mac_stats = &efx->mac_stats;
struct net_device_stats *stats = &net_dev->stats;
- /* Update stats if possible, but do not wait if another thread
- * is updating them or if MAC stats fetches are temporarily
- * disabled; slightly stale stats are acceptable.
- */
- if (!spin_trylock(&efx->stats_lock))
- return stats;
- if (!efx->stats_disable_count) {
- efx->mac_op->update_stats(efx);
- falcon_update_nic_stats(efx);
- }
- spin_unlock(&efx->stats_lock);
+ spin_lock_bh(&efx->stats_lock);
+ falcon_update_nic_stats(efx);
+ spin_unlock_bh(&efx->stats_lock);
stats->rx_packets = mac_stats->rx_packets;
stats->tx_packets = mac_stats->tx_packets;
@@ -1726,7 +1709,6 @@
{
EFX_ASSERT_RESET_SERIALISED(efx);
- efx_stats_disable(efx);
efx_stop_all(efx);
mutex_lock(&efx->mac_lock);
mutex_lock(&efx->spi_lock);
@@ -1776,10 +1758,8 @@
mutex_unlock(&efx->spi_lock);
mutex_unlock(&efx->mac_lock);
- if (ok) {
+ if (ok)
efx_start_all(efx);
- efx_stats_enable(efx);
- }
return rc;
}
@@ -1977,7 +1957,6 @@
efx->rx_checksum_enabled = true;
spin_lock_init(&efx->netif_stop_lock);
spin_lock_init(&efx->stats_lock);
- efx->stats_disable_count = 1;
mutex_init(&efx->mac_lock);
efx->mac_op = &efx_dummy_mac_operations;
efx->phy_op = &efx_dummy_phy_operations;
@@ -2219,9 +2198,8 @@
goto fail4;
}
- /* Switch to the running state before we expose the device to
- * the OS. This is to ensure that the initial gathering of
- * MAC stats succeeds. */
+ /* Switch to the running state before we expose the device to the OS,
+ * so that dev_open()|efx_start_all() will actually start the device */
efx->state = STATE_RUNNING;
rc = efx_register_netdev(efx);