diff options
| author |   Cong Wang <xiyou.wangcong@gmail.com> | 2018-01-25 18:26:23 -0800 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2018-01-29 12:42:15 -0500 |
| commit | 48bfd55e7e4149a304e89c1999436cf52d094a27 (patch) | |
| tree | 6318e75ea99c74a81622ebe82ee2c71c9338baf4 /net | |
| parent | net: introduce helper dev_change_tx_queue_len() (diff) | |
| download | linux-dev-48bfd55e7e4149a304e89c1999436cf52d094a27.tar.xz linux-dev-48bfd55e7e4149a304e89c1999436cf52d094a27.zip | |
net_sched: plug in qdisc ops change_tx_queue_len
Introduce a new qdisc ops ->change_tx_queue_len() so that
each qdisc could decide how to implement this if it wants.
Previously we simply read dev->tx_queue_len, after pfifo_fast
switches to skb array, we need this API to resize the skb array
when we change dev->tx_queue_len.
To avoid handling race conditions with TX BH, we need to
deactivate all TX queues before change the value and bring them
back after we are done, this also makes implementation easier.
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/dev.c | 1 | ||||
| -rw-r--r-- | net/sched/sch_generic.c | 33 |
2 files changed, 34 insertions, 0 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 520c24671bc5..dda9d7b9a840 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7070,6 +7070,7 @@ int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) dev->tx_queue_len = orig_len; return res; } + return dev_qdisc_change_tx_queue_len(dev); } return 0; diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 1816bde47256..08f9fa27e06e 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -1178,6 +1178,39 @@ void dev_deactivate(struct net_device *dev) } EXPORT_SYMBOL(dev_deactivate); +static int qdisc_change_tx_queue_len(struct net_device *dev, + struct netdev_queue *dev_queue) +{ + struct Qdisc *qdisc = dev_queue->qdisc_sleeping; + const struct Qdisc_ops *ops = qdisc->ops; + + if (ops->change_tx_queue_len) + return ops->change_tx_queue_len(qdisc, dev->tx_queue_len); + return 0; +} + +int dev_qdisc_change_tx_queue_len(struct net_device *dev) +{ + bool up = dev->flags & IFF_UP; + unsigned int i; + int ret = 0; + + if (up) + dev_deactivate(dev); + + for (i = 0; i < dev->num_tx_queues; i++) { + ret = qdisc_change_tx_queue_len(dev, &dev->_tx[i]); + + /* TODO: revert changes on a partial failure */ + if (ret) + break; + } + + if (up) + dev_activate(dev); + return ret; +} + static void dev_init_scheduler_queue(struct net_device *dev, struct netdev_queue *dev_queue, void *_qdisc) |