From d7be97756f8a4874ac17003de5843c742dd84153 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Mon, 9 Jul 2018 12:19:32 -0400 Subject: net-sysfs: Drop support for XPS and traffic_class on single queue device This patch makes it so that we do not report the traffic class or allow XPS configuration on single queue devices. This is mostly to avoid unnecessary complexity with changes I have planned that will allow us to reuse the unused tc_to_txq and XPS configuration on a single queue device to allow it to make use of a subset of queues on an underlying device. Signed-off-by: Alexander Duyck Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- net/core/net-sysfs.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'net/core/net-sysfs.c') diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index f25ac5ff48a6..dce3ae0fbca2 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1047,9 +1047,14 @@ static ssize_t traffic_class_show(struct netdev_queue *queue, char *buf) { struct net_device *dev = queue->dev; - int index = get_netdev_queue_index(queue); - int tc = netdev_txq_to_tc(dev, index); + int index; + int tc; + if (!netif_is_multiqueue(dev)) + return -ENOENT; + + index = get_netdev_queue_index(queue); + tc = netdev_txq_to_tc(dev, index); if (tc < 0) return -EINVAL; @@ -1214,6 +1219,9 @@ static ssize_t xps_cpus_show(struct netdev_queue *queue, cpumask_var_t mask; unsigned long index; + if (!netif_is_multiqueue(dev)) + return -ENOENT; + index = get_netdev_queue_index(queue); if (dev->num_tc) { @@ -1260,6 +1268,9 @@ static ssize_t xps_cpus_store(struct netdev_queue *queue, cpumask_var_t mask; int err; + if (!netif_is_multiqueue(dev)) + return -ENOENT; + if (!capable(CAP_NET_ADMIN)) return -EPERM; -- cgit v1.2.3 From ffcfe25bb50f27395e15fa999f1a7eb769f55360 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Mon, 9 Jul 2018 12:19:38 -0400 Subject: net: Add support for subordinate device traffic classes This patch is meant to provide the basic tools needed to allow us to create subordinate device traffic classes. The general idea here is to allow subdividing the queues of a device into queue groups accessible through an upper device such as a macvlan. The idea here is to enforce the idea that an upper device has to be a single queue device, ideally with IFF_NO_QUQUE set. With that being the case we can pretty much guarantee that the tc_to_txq mappings and XPS maps for the upper device are unused. As such we could reuse those in order to support subdividing the lower device and distributing those queues between the subordinate devices. In order to distinguish between a regular set of traffic classes and if a device is carrying subordinate traffic classes I changed num_tc from a u8 to a s16 value and use the negative values to represent the subordinate pool values. So starting at -1 and running to -32768 we can encode those as pool values, and the existing values of 0 to 15 can be maintained. Signed-off-by: Alexander Duyck Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- net/core/net-sysfs.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) (limited to 'net/core/net-sysfs.c') diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index dce3ae0fbca2..ffa1d18f2c2c 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1054,11 +1054,23 @@ static ssize_t traffic_class_show(struct netdev_queue *queue, return -ENOENT; index = get_netdev_queue_index(queue); + + /* If queue belongs to subordinate dev use its TC mapping */ + dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; + tc = netdev_txq_to_tc(dev, index); if (tc < 0) return -EINVAL; - return sprintf(buf, "%u\n", tc); + /* We can report the traffic class one of two ways: + * Subordinate device traffic classes are reported with the traffic + * class first, and then the subordinate class so for example TC0 on + * subordinate device 2 will be reported as "0-2". If the queue + * belongs to the root device it will be reported with just the + * traffic class, so just "0" for TC 0 for example. + */ + return dev->num_tc < 0 ? sprintf(buf, "%u%d\n", tc, dev->num_tc) : + sprintf(buf, "%u\n", tc); } #ifdef CONFIG_XPS @@ -1225,7 +1237,14 @@ static ssize_t xps_cpus_show(struct netdev_queue *queue, index = get_netdev_queue_index(queue); if (dev->num_tc) { + /* Do not allow XPS on subordinate device directly */ num_tc = dev->num_tc; + if (num_tc < 0) + return -EINVAL; + + /* If queue belongs to subordinate dev use its map */ + dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; + tc = netdev_txq_to_tc(dev, index); if (tc < 0) return -EINVAL; -- cgit v1.2.3