tcp: add generic netlink support for tcp_metrics
Add support for genl "tcp_metrics". No locking
is changed, only that now we can unlink and delete
entries after grace period. We implement get/del for
single entry and dump to support show/flush filtering
in user space. Del without address attribute causes
flush for all addresses, sadly under genl_mutex.
v2:
- remove rcu_assign_pointer as suggested by Eric Dumazet,
it is not needed because there are no other writes under lock
- move the flushing code in tcp_metrics_flush_all
v3:
- remove synchronize_rcu on flush as suggested by Eric Dumazet
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/tcp_metrics.h b/include/linux/tcp_metrics.h
new file mode 100644
index 0000000..cb5157b
--- /dev/null
+++ b/include/linux/tcp_metrics.h
@@ -0,0 +1,54 @@
+/* tcp_metrics.h - TCP Metrics Interface */
+
+#ifndef _LINUX_TCP_METRICS_H
+#define _LINUX_TCP_METRICS_H
+
+#include <linux/types.h>
+
+/* NETLINK_GENERIC related info
+ */
+#define TCP_METRICS_GENL_NAME "tcp_metrics"
+#define TCP_METRICS_GENL_VERSION 0x1
+
+enum tcp_metric_index {
+ TCP_METRIC_RTT,
+ TCP_METRIC_RTTVAR,
+ TCP_METRIC_SSTHRESH,
+ TCP_METRIC_CWND,
+ TCP_METRIC_REORDERING,
+
+ /* Always last. */
+ __TCP_METRIC_MAX,
+};
+
+#define TCP_METRIC_MAX (__TCP_METRIC_MAX - 1)
+
+enum {
+ TCP_METRICS_ATTR_UNSPEC,
+ TCP_METRICS_ATTR_ADDR_IPV4, /* u32 */
+ TCP_METRICS_ATTR_ADDR_IPV6, /* binary */
+ TCP_METRICS_ATTR_AGE, /* msecs */
+ TCP_METRICS_ATTR_TW_TSVAL, /* u32, raw, rcv tsval */
+ TCP_METRICS_ATTR_TW_TS_STAMP, /* s32, sec age */
+ TCP_METRICS_ATTR_VALS, /* nested +1, u32 */
+ TCP_METRICS_ATTR_FOPEN_MSS, /* u16 */
+ TCP_METRICS_ATTR_FOPEN_SYN_DROPS, /* u16, count of drops */
+ TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS, /* msecs age */
+ TCP_METRICS_ATTR_FOPEN_COOKIE, /* binary */
+
+ __TCP_METRICS_ATTR_MAX,
+};
+
+#define TCP_METRICS_ATTR_MAX (__TCP_METRICS_ATTR_MAX - 1)
+
+enum {
+ TCP_METRICS_CMD_UNSPEC,
+ TCP_METRICS_CMD_GET,
+ TCP_METRICS_CMD_DEL,
+
+ __TCP_METRICS_CMD_MAX,
+};
+
+#define TCP_METRICS_CMD_MAX (__TCP_METRICS_CMD_MAX - 1)
+
+#endif /* _LINUX_TCP_METRICS_H */