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netdev: Move atomic queue state bits into netdev_queue.
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Signed-off-by: David S. Miller <davem@davemloft.net>
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David S. Miller committed Jul 9, 2008
1 parent b19fa1f commit 79d1638
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Showing 3 changed files with 51 additions and 26 deletions.
55 changes: 39 additions & 16 deletions include/linux/netdevice.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -281,14 +281,12 @@ struct header_ops {

enum netdev_state_t
{
__LINK_STATE_XOFF=0,
__LINK_STATE_START,
__LINK_STATE_PRESENT,
__LINK_STATE_SCHED,
__LINK_STATE_NOCARRIER,
__LINK_STATE_LINKWATCH_PENDING,
__LINK_STATE_DORMANT,
__LINK_STATE_QDISC_RUNNING,
};


Expand Down Expand Up @@ -448,10 +446,17 @@ static inline void napi_synchronize(const struct napi_struct *n)
# define napi_synchronize(n) barrier()
#endif

enum netdev_queue_state_t
{
__QUEUE_STATE_XOFF,
__QUEUE_STATE_QDISC_RUNNING,
};

struct netdev_queue {
spinlock_t lock;
struct net_device *dev;
struct Qdisc *qdisc;
unsigned long state;
struct sk_buff *gso_skb;
spinlock_t _xmit_lock;
int xmit_lock_owner;
Expand Down Expand Up @@ -952,9 +957,7 @@ extern void __netif_schedule(struct netdev_queue *txq);

static inline void netif_schedule_queue(struct netdev_queue *txq)
{
struct net_device *dev = txq->dev;

if (!test_bit(__LINK_STATE_XOFF, &dev->state))
if (!test_bit(__QUEUE_STATE_XOFF, &txq->state))
__netif_schedule(txq);
}

Expand All @@ -969,9 +972,14 @@ static inline void netif_schedule(struct net_device *dev)
*
* Allow upper layers to call the device hard_start_xmit routine.
*/
static inline void netif_tx_start_queue(struct netdev_queue *dev_queue)
{
clear_bit(__QUEUE_STATE_XOFF, &dev_queue->state);
}

static inline void netif_start_queue(struct net_device *dev)
{
clear_bit(__LINK_STATE_XOFF, &dev->state);
netif_tx_start_queue(&dev->tx_queue);
}

/**
Expand All @@ -981,16 +989,21 @@ static inline void netif_start_queue(struct net_device *dev)
* Allow upper layers to call the device hard_start_xmit routine.
* Used for flow control when transmit resources are available.
*/
static inline void netif_wake_queue(struct net_device *dev)
static inline void netif_tx_wake_queue(struct netdev_queue *dev_queue)
{
#ifdef CONFIG_NETPOLL_TRAP
if (netpoll_trap()) {
clear_bit(__LINK_STATE_XOFF, &dev->state);
clear_bit(__QUEUE_STATE_XOFF, &dev_queue->state);
return;
}
#endif
if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state))
__netif_schedule(&dev->tx_queue);
if (test_and_clear_bit(__QUEUE_STATE_XOFF, &dev_queue->state))
__netif_schedule(dev_queue);
}

static inline void netif_wake_queue(struct net_device *dev)
{
netif_tx_wake_queue(&dev->tx_queue);
}

/**
Expand All @@ -1000,9 +1013,14 @@ static inline void netif_wake_queue(struct net_device *dev)
* Stop upper layers calling the device hard_start_xmit routine.
* Used for flow control when transmit resources are unavailable.
*/
static inline void netif_tx_stop_queue(struct netdev_queue *dev_queue)
{
set_bit(__QUEUE_STATE_XOFF, &dev_queue->state);
}

static inline void netif_stop_queue(struct net_device *dev)
{
set_bit(__LINK_STATE_XOFF, &dev->state);
netif_tx_stop_queue(&dev->tx_queue);
}

/**
Expand All @@ -1011,9 +1029,14 @@ static inline void netif_stop_queue(struct net_device *dev)
*
* Test if transmit queue on device is currently unable to send.
*/
static inline int netif_tx_queue_stopped(const struct netdev_queue *dev_queue)
{
return test_bit(__QUEUE_STATE_XOFF, &dev_queue->state);
}

static inline int netif_queue_stopped(const struct net_device *dev)
{
return test_bit(__LINK_STATE_XOFF, &dev->state);
return netif_tx_queue_stopped(&dev->tx_queue);
}

/**
Expand Down Expand Up @@ -1043,7 +1066,7 @@ static inline int netif_running(const struct net_device *dev)
*/
static inline void netif_start_subqueue(struct net_device *dev, u16 queue_index)
{
clear_bit(__LINK_STATE_XOFF, &dev->egress_subqueue[queue_index].state);
clear_bit(__QUEUE_STATE_XOFF, &dev->egress_subqueue[queue_index].state);
}

/**
Expand All @@ -1059,7 +1082,7 @@ static inline void netif_stop_subqueue(struct net_device *dev, u16 queue_index)
if (netpoll_trap())
return;
#endif
set_bit(__LINK_STATE_XOFF, &dev->egress_subqueue[queue_index].state);
set_bit(__QUEUE_STATE_XOFF, &dev->egress_subqueue[queue_index].state);
}

/**
Expand All @@ -1072,7 +1095,7 @@ static inline void netif_stop_subqueue(struct net_device *dev, u16 queue_index)
static inline int __netif_subqueue_stopped(const struct net_device *dev,
u16 queue_index)
{
return test_bit(__LINK_STATE_XOFF,
return test_bit(__QUEUE_STATE_XOFF,
&dev->egress_subqueue[queue_index].state);
}

Expand All @@ -1095,7 +1118,7 @@ static inline void netif_wake_subqueue(struct net_device *dev, u16 queue_index)
if (netpoll_trap())
return;
#endif
if (test_and_clear_bit(__LINK_STATE_XOFF,
if (test_and_clear_bit(__QUEUE_STATE_XOFF,
&dev->egress_subqueue[queue_index].state))
__netif_schedule(&dev->tx_queue);
}
Expand Down
2 changes: 1 addition & 1 deletion include/net/pkt_sched.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -91,7 +91,7 @@ static inline void qdisc_run(struct netdev_queue *txq)
struct net_device *dev = txq->dev;

if (!netif_queue_stopped(dev) &&
!test_and_set_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
!test_and_set_bit(__QUEUE_STATE_QDISC_RUNNING, &txq->state))
__qdisc_run(txq);
}

Expand Down
20 changes: 11 additions & 9 deletions net/sched/sch_generic.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -121,9 +121,9 @@ static inline int handle_dev_cpu_collision(struct sk_buff *skb,
/*
* NOTE: Called under queue->lock with locally disabled BH.
*
* __LINK_STATE_QDISC_RUNNING guarantees only one CPU can process this
* device at a time. queue->lock serializes queue accesses for
* this device AND txq->qdisc pointer itself.
* __QUEUE_STATE_QDISC_RUNNING guarantees only one CPU can process
* this queue at a time. queue->lock serializes queue accesses for
* this queue AND txq->qdisc pointer itself.
*
* netif_tx_lock serializes accesses to device driver.
*
Expand Down Expand Up @@ -206,7 +206,7 @@ void __qdisc_run(struct netdev_queue *txq)
}
}

clear_bit(__LINK_STATE_QDISC_RUNNING, &dev->state);
clear_bit(__QUEUE_STATE_QDISC_RUNNING, &txq->state);
}

static void dev_watchdog(unsigned long arg)
Expand Down Expand Up @@ -605,9 +605,10 @@ static void dev_deactivate_queue(struct netdev_queue *dev_queue,

void dev_deactivate(struct net_device *dev)
{
struct netdev_queue *dev_queue = &dev->tx_queue;
int running;

dev_deactivate_queue(&dev->tx_queue, &noop_qdisc);
dev_deactivate_queue(dev_queue, &noop_qdisc);

dev_watchdog_down(dev);

Expand All @@ -616,16 +617,17 @@ void dev_deactivate(struct net_device *dev)

/* Wait for outstanding qdisc_run calls. */
do {
while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
while (test_bit(__QUEUE_STATE_QDISC_RUNNING, &dev_queue->state))
yield();

/*
* Double-check inside queue lock to ensure that all effects
* of the queue run are visible when we return.
*/
spin_lock_bh(&dev->tx_queue.lock);
running = test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state);
spin_unlock_bh(&dev->tx_queue.lock);
spin_lock_bh(&dev_queue->lock);
running = test_bit(__QUEUE_STATE_QDISC_RUNNING,
&dev_queue->state);
spin_unlock_bh(&dev_queue->lock);

/*
* The running flag should never be set at this point because
Expand Down

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