Commit 92af3e95 authored by Jesse Brandeburg's avatar Jesse Brandeburg Committed by David S. Miller
Browse files

e1000e: drop lltx, remove unnecessary lock 



LLTX is deprecated and complicated, don't use it.  It was observed by Don Ash
<donash4@gmail.com> that e1000e was acquiring this lock in the NAPI cleanup
path.  This is obviously a bug, as this is a leftover from when e1000
supported multiple tx queues and fake netdevs.

another user reported this to us and tested routing with the 2.6.27 kernel and
this patch and reported a 3.5 % improvement in packets forwarded in a
multi-port test on 82571 parts.

Signed-off-by: default avatarJesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: default avatarBruce Allan <bruce.w.allan@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5ef3041e

drivers/net/e1000e/e1000.h

+0 −2
Original line number Diff line number Diff line
@@ -195,8 +195,6 @@ struct e1000_adapter { 
	u16 link_duplex;

	u16 eeprom_vers;



	spinlock_t tx_queue_lock; /* prevent concurrent tail updates */



	/* track device up/down/testing state */

	unsigned long state;

drivers/net/e1000e/netdev.c

+3 −31
Original line number Diff line number Diff line
@@ -47,7 +47,7 @@ 


#include "e1000.h"



#define DRV_VERSION "0.3.3.3-k6"

#define DRV_VERSION "0.3.3.4-k2"

char e1000e_driver_name[] = "e1000e";

const char e1000e_driver_version[] = DRV_VERSION;
@@ -1698,7 +1698,6 @@ int e1000e_setup_tx_resources(struct e1000_adapter *adapter) 


	tx_ring->next_to_use = 0;

	tx_ring->next_to_clean = 0;

	spin_lock_init(&adapter->tx_queue_lock);



	return 0;

err:
@@ -2007,16 +2006,7 @@ static int e1000_clean(struct napi_struct *napi, int budget) 
	    !(adapter->rx_ring->ims_val & adapter->tx_ring->ims_val))

		goto clean_rx;



	/*

	 * e1000_clean is called per-cpu.  This lock protects

	 * tx_ring from being cleaned by multiple cpus

	 * simultaneously.  A failure obtaining the lock means

	 * tx_ring is currently being cleaned anyway.

	 */

	if (spin_trylock(&adapter->tx_queue_lock)) {

	tx_cleaned = e1000_clean_tx_irq(adapter);

		spin_unlock(&adapter->tx_queue_lock);

	}



clean_rx:

	adapter->clean_rx(adapter, &work_done, budget);
@@ -2922,8 +2912,6 @@ static int __devinit e1000_sw_init(struct e1000_adapter *adapter) 
	if (e1000_alloc_queues(adapter))

		return -ENOMEM;



	spin_lock_init(&adapter->tx_queue_lock);



	/* Explicitly disable IRQ since the NIC can be in any state. */

	e1000_irq_disable(adapter);
@@ -4069,7 +4057,6 @@ static int e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev) 
	unsigned int max_txd_pwr = E1000_MAX_TXD_PWR;

	unsigned int tx_flags = 0;

	unsigned int len = skb->len - skb->data_len;

	unsigned long irq_flags;

	unsigned int nr_frags;

	unsigned int mss;

	int count = 0;
@@ -4138,18 +4125,12 @@ static int e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev) 
	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;



	/*

	 * 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, count + 2))

		return NETDEV_TX_BUSY;

	}



	if (adapter->vlgrp && vlan_tx_tag_present(skb)) {

		tx_flags |= E1000_TX_FLAGS_VLAN;
@@ -4161,7 +4142,6 @@ static int e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev) 
	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;

	}
@@ -4182,7 +4162,6 @@ static int e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev) 
	if (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_OK;

	}
@@ -4193,7 +4172,6 @@ static int e1000_xmit_frame(struct sk_buff *skb, struct net_device *netdev) 
	/* 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;

}
@@ -4922,12 +4900,6 @@ static int __devinit e1000_probe(struct pci_dev *pdev, 
	if (pci_using_dac)

		netdev->features |= NETIF_F_HIGHDMA;



	/*

	 * We should not be using LLTX anymore, but we are still Tx faster with

	 * it.

	 */

	netdev->features |= NETIF_F_LLTX;



	if (e1000e_enable_mng_pass_thru(&adapter->hw))

		adapter->flags |= FLAG_MNG_PT_ENABLED;

CRA Git | Maintained and supported by SUSTech CRA and CCSE