net: add socket option for low latency polling
adds a socket option for low latency polling.
This allows overriding the global sysctl value with a per-socket one.
Unexport sysctl_net_ll_poll since for now it's not needed in modules.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/sock.c b/net/core/sock.c
index 788c0da..1e744b1 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -913,6 +913,19 @@
sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
break;
+#ifdef CONFIG_NET_LL_RX_POLL
+ case SO_LL:
+ /* allow unprivileged users to decrease the value */
+ if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
+ ret = -EPERM;
+ else {
+ if (val < 0)
+ ret = -EINVAL;
+ else
+ sk->sk_ll_usec = val;
+ }
+ break;
+#endif
default:
ret = -ENOPROTOOPT;
break;
@@ -1170,6 +1183,12 @@
v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
break;
+#ifdef CONFIG_NET_LL_RX_POLL
+ case SO_LL:
+ v.val = sk->sk_ll_usec;
+ break;
+#endif
+
default:
return -ENOPROTOOPT;
}
@@ -2288,6 +2307,7 @@
#ifdef CONFIG_NET_LL_RX_POLL
sk->sk_napi_id = 0;
+ sk->sk_ll_usec = sysctl_net_ll_poll;
#endif
/*