From 060212928670593fb89243640bf05cf89560b023 Mon Sep 17 00:00:00 2001
From: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Date: Mon, 10 Jun 2013 11:39:50 +0300
Subject: net: add low latency socket poll
Adds an ndo_ll_poll method and the code that supports it.
This method can be used by low latency applications to busy-poll
Ethernet device queues directly from the socket code.
sysctl_net_ll_poll controls how many microseconds to poll.
Default is zero (disabled).
Individual protocol support will be added by subsequent patches.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/core/skbuff.c | 4 ++++
net/core/sock.c | 6 ++++++
net/core/sysctl_net_core.c | 10 ++++++++++
3 files changed, 20 insertions(+)
(limited to 'net/core')
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 73f57a0e1523..4a4181e16c1a 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -733,6 +733,10 @@ static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
new->vlan_tci = old->vlan_tci;
skb_copy_secmark(new, old);
+
+#ifdef CONFIG_NET_LL_RX_POLL
+ new->napi_id = old->napi_id;
+#endif
}
/*
diff --git a/net/core/sock.c b/net/core/sock.c
index 88868a9d21da..788c0da5eed1 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -139,6 +139,8 @@
#include <net/tcp.h>
#endif
+#include <net/ll_poll.h>
+
static DEFINE_MUTEX(proto_list_mutex);
static LIST_HEAD(proto_list);
@@ -2284,6 +2286,10 @@ void sock_init_data(struct socket *sock, struct sock *sk)
sk->sk_stamp = ktime_set(-1L, 0);
+#ifdef CONFIG_NET_LL_RX_POLL
+ sk->sk_napi_id = 0;
+#endif
+
/*
* Before updating sk_refcnt, we must commit prior changes to memory
* (Documentation/RCU/rculist_nulls.txt for details)
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index 741db5fc7806..4b48f39582b0 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -19,6 +19,7 @@
#include <net/ip.h>
#include <net/sock.h>
#include <net/net_ratelimit.h>
+#include <net/ll_poll.h>
static int one = 1;
@@ -284,6 +285,15 @@ static struct ctl_table net_core_table[] = {
.proc_handler = flow_limit_table_len_sysctl
},
#endif /* CONFIG_NET_FLOW_LIMIT */
+#ifdef CONFIG_NET_LL_RX_POLL
+ {
+ .procname = "low_latency_poll",
+ .data = &sysctl_net_ll_poll,
+ .maxlen = sizeof(unsigned long),
+ .mode = 0644,
+ .proc_handler = proc_doulongvec_minmax
+ },
+#endif
#endif /* CONFIG_NET */
{
.procname = "netdev_budget",
--
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