diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-net-queues | 8 | ||||
| -rw-r--r-- | Documentation/networking/scaling.txt | 9 | ||||
| -rw-r--r-- | include/linux/netdevice.h | 8 | ||||
| -rw-r--r-- | net/core/net-sysfs.c | 67 |
4 files changed, 80 insertions, 12 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-net-queues b/Documentation/ABI/testing/sysfs-class-net-queues index 5e9aeb91d355..0c0df91b1516 100644 --- a/Documentation/ABI/testing/sysfs-class-net-queues +++ b/Documentation/ABI/testing/sysfs-class-net-queues @@ -24,6 +24,14 @@ Description: Indicates the number of transmit timeout events seen by this network interface transmit queue. +What: /sys/class/<iface>/queues/tx-<queue>/tx_maxrate +Date: March 2015 +KernelVersion: 4.1 +Contact: netdev@vger.kernel.org +Description: + A Mbps max-rate set for the queue, a value of zero means disabled, + default is disabled. + What: /sys/class/<iface>/queues/tx-<queue>/xps_cpus Date: November 2010 KernelVersion: 2.6.38 diff --git a/Documentation/networking/scaling.txt b/Documentation/networking/scaling.txt index 99ca40e8e810..cbfac0949635 100644 --- a/Documentation/networking/scaling.txt +++ b/Documentation/networking/scaling.txt @@ -421,6 +421,15 @@ best CPUs to share a given queue are probably those that share the cache with the CPU that processes transmit completions for that queue (transmit interrupts). +Per TX Queue rate limitation: +============================= + +These are rate-limitation mechanisms implemented by HW, where currently +a max-rate attribute is supported, by setting a Mbps value to + +/sys/class/net/<dev>/queues/tx-<n>/tx_maxrate + +A value of zero means disabled, and this is the default. Further Information =================== diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index dd1d069758be..76c5de4978a8 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -587,6 +587,7 @@ struct netdev_queue { #ifdef CONFIG_BQL struct dql dql; #endif + unsigned long tx_maxrate; } ____cacheline_aligned_in_smp; static inline int netdev_queue_numa_node_read(const struct netdev_queue *q) @@ -1022,6 +1023,10 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev, * be otherwise expressed by feature flags. The check is called with * the set of features that the stack has calculated and it returns * those the driver believes to be appropriate. + * int (*ndo_set_tx_maxrate)(struct net_device *dev, + * int queue_index, u32 maxrate); + * Called when a user wants to set a max-rate limitation of specific + * TX queue. */ struct net_device_ops { int (*ndo_init)(struct net_device *dev); @@ -1178,6 +1183,9 @@ struct net_device_ops { netdev_features_t (*ndo_features_check) (struct sk_buff *skb, struct net_device *dev, netdev_features_t features); + int (*ndo_set_tx_maxrate)(struct net_device *dev, + int queue_index, + u32 maxrate); }; /** diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index cf30620a88e1..7e58bd7ec232 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -951,6 +951,60 @@ static ssize_t show_trans_timeout(struct netdev_queue *queue, return sprintf(buf, "%lu", trans_timeout); } +#ifdef CONFIG_XPS +static inline unsigned int get_netdev_queue_index(struct netdev_queue *queue) +{ + struct net_device *dev = queue->dev; + int i; + + for (i = 0; i < dev->num_tx_queues; i++) + if (queue == &dev->_tx[i]) + break; + + BUG_ON(i >= dev->num_tx_queues); + + return i; +} + +static ssize_t show_tx_maxrate(struct netdev_queue *queue, + struct netdev_queue_attribute *attribute, + char *buf) +{ + return sprintf(buf, "%lu\n", queue->tx_maxrate); +} + +static ssize_t set_tx_maxrate(struct netdev_queue *queue, + struct netdev_queue_attribute *attribute, + const char *buf, size_t len) +{ + struct net_device *dev = queue->dev; + int err, index = get_netdev_queue_index(queue); + u32 rate = 0; + + err = kstrtou32(buf, 10, &rate); + if (err < 0) + return err; + + if (!rtnl_trylock()) + return restart_syscall(); + + err = -EOPNOTSUPP; + if (dev->netdev_ops->ndo_set_tx_maxrate) + err = dev->netdev_ops->ndo_set_tx_maxrate(dev, index, rate); + + rtnl_unlock(); + if (!err) { + queue->tx_maxrate = rate; + return len; + } + return err; +} + +static struct netdev_queue_attribute queue_tx_maxrate = + __ATTR(tx_maxrate, S_IRUGO | S_IWUSR, + show_tx_maxrate, set_tx_maxrate); +#endif + static struct netdev_queue_attribute queue_trans_timeout = __ATTR(tx_timeout, S_IRUGO, show_trans_timeout, NULL); @@ -1065,18 +1119,6 @@ static struct attribute_group dql_group = { #endif /* CONFIG_BQL */ #ifdef CONFIG_XPS -static unsigned int get_netdev_queue_index(struct netdev_queue *queue) -{ - struct net_device *dev = queue->dev; - unsigned int i; - - i = queue - dev->_tx; - BUG_ON(i >= dev->num_tx_queues); - - return i; -} - - static ssize_t show_xps_map(struct netdev_queue *queue, struct netdev_queue_attribute *attribute, char *buf) { @@ -1153,6 +1195,7 @@ static struct attribute *netdev_queue_default_attrs[] = { &queue_trans_timeout.attr, #ifdef CONFIG_XPS &xps_cpus_attribute.attr, + &queue_tx_maxrate.attr, #endif NULL }; |