diff options
| -rw-r--r-- | Documentation/sysctl/net.txt | 22 | ||||
| -rw-r--r-- | include/linux/netdevice.h | 6 | ||||
| -rw-r--r-- | net/core/ethtool.c | 11 | ||||
| -rw-r--r-- | net/core/sysctl_net_core.c | 19 |
4 files changed, 58 insertions, 0 deletions
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt index e26c607468a6..666594b43cff 100644 --- a/Documentation/sysctl/net.txt +++ b/Documentation/sysctl/net.txt @@ -142,6 +142,28 @@ netdev_max_backlog Maximum number of packets, queued on the INPUT side, when the interface receives packets faster than kernel can process them. +netdev_rss_key +-------------- + +RSS (Receive Side Scaling) enabled drivers use a 40 bytes host key that is +randomly generated. +Some user space might need to gather its content even if drivers do not +provide ethtool -x support yet. + +myhost:~# cat /proc/sys/net/core/netdev_rss_key +84:50:f4:00:a8:15:d1:a7:e9:7f:1d:60:35:c7:47:25:42:97:74:ca:56:bb:b6:a1:d8: ... (52 bytes total) + +File contains nul bytes if no driver ever called netdev_rss_key_fill() function. +Note: +/proc/sys/net/core/netdev_rss_key contains 52 bytes of key, +but most drivers only use 40 bytes of it. + +myhost:~# ethtool -x eth0 +RX flow hash indirection table for eth0 with 8 RX ring(s): + 0: 0 1 2 3 4 5 6 7 +RSS hash key: +84:50:f4:00:a8:15:d1:a7:e9:7f:1d:60:35:c7:47:25:42:97:74:ca:56:bb:b6:a1:d8:43:e3:c9:0c:fd:17:55:c2:3a:4d:69:ed:f1:42:89 + netdev_tstamp_prequeue ---------------------- diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 4a6f770377d3..db63cf459ba1 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3422,6 +3422,12 @@ void netdev_upper_dev_unlink(struct net_device *dev, void netdev_adjacent_rename_links(struct net_device *dev, char *oldname); void *netdev_lower_dev_get_private(struct net_device *dev, struct net_device *lower_dev); + +/* RSS keys are 40 or 52 bytes long */ +#define NETDEV_RSS_KEY_LEN 52 +extern u8 netdev_rss_key[NETDEV_RSS_KEY_LEN]; +void netdev_rss_key_fill(void *buffer, size_t len); + int dev_get_nest_level(struct net_device *dev, bool (*type_check)(struct net_device *dev)); int skb_checksum_help(struct sk_buff *skb); diff --git a/net/core/ethtool.c b/net/core/ethtool.c index b0f84f5ddda8..715f51f321e9 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -25,6 +25,7 @@ #include <linux/slab.h> #include <linux/rtnetlink.h> #include <linux/sched.h> +#include <linux/net.h> /* * Some useful ethtool_ops methods that're device independent. @@ -573,6 +574,16 @@ static int ethtool_copy_validate_indir(u32 *indir, void __user *useraddr, return 0; } +u8 netdev_rss_key[NETDEV_RSS_KEY_LEN]; + +void netdev_rss_key_fill(void *buffer, size_t len) +{ + BUG_ON(len > sizeof(netdev_rss_key)); + net_get_random_once(netdev_rss_key, sizeof(netdev_rss_key)); + memcpy(buffer, netdev_rss_key, len); +} +EXPORT_SYMBOL(netdev_rss_key_fill); + static noinline_for_stack int ethtool_get_rxfh_indir(struct net_device *dev, void __user *useraddr) { diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index f93f092fe226..31baba2a71ce 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -217,6 +217,18 @@ static int set_default_qdisc(struct ctl_table *table, int write, } #endif +static int proc_do_rss_key(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table fake_table; + char buf[NETDEV_RSS_KEY_LEN * 3]; + + snprintf(buf, sizeof(buf), "%*phC", NETDEV_RSS_KEY_LEN, netdev_rss_key); + fake_table.data = buf; + fake_table.maxlen = sizeof(buf); + return proc_dostring(&fake_table, write, buffer, lenp, ppos); +} + static struct ctl_table net_core_table[] = { #ifdef CONFIG_NET { @@ -265,6 +277,13 @@ static struct ctl_table net_core_table[] = { .mode = 0644, .proc_handler = proc_dointvec }, + { + .procname = "netdev_rss_key", + .data = &netdev_rss_key, + .maxlen = sizeof(int), + .mode = 0444, + .proc_handler = proc_do_rss_key, + }, #ifdef CONFIG_BPF_JIT { .procname = "bpf_jit_enable", |