From: Krishna Kumar <krkumar2@in•ibm.com>
To: davem@davemloft•net, arnd@arndb•de
Cc: bhutchings@solarflare•com, netdev@vger•kernel.org,
therbert@google•com, Krishna Kumar <krkumar2@in•ibm.com>,
mst@redhat•com
Subject: [PATCH v2 1/2] core: Factor out flow calculation from get_rps_cpu
Date: Mon, 02 Aug 2010 20:03:04 +0530 [thread overview]
Message-ID: <20100802143304.1517.42494.sendpatchset@krkumar2.in.ibm.com> (raw)
From: Krishna Kumar <krkumar2@in•ibm.com>
Factor out flow calculation code from get_rps_cpu, since macvtap
driver can use the same code.
Signed-off-by: Krishna Kumar <krkumar2@in•ibm.com>
---
net/core/dev.c | 94 +++++++++++++++++++++++++++++------------------
1 file changed, 58 insertions(+), 36 deletions(-)
diff -ruNp org/net/core/dev.c new/net/core/dev.c
--- org/net/core/dev.c 2010-08-02 10:06:59.000000000 +0530
+++ new/net/core/dev.c 2010-08-02 19:29:34.000000000 +0530
@@ -2263,51 +2263,24 @@ static inline void ____napi_schedule(str
__raise_softirq_irqoff(NET_RX_SOFTIRQ);
}
-#ifdef CONFIG_RPS
-
-/* One global table that all flow-based protocols share. */
-struct rps_sock_flow_table *rps_sock_flow_table __read_mostly;
-EXPORT_SYMBOL(rps_sock_flow_table);
-
/*
- * get_rps_cpu is called from netif_receive_skb and returns the target
- * CPU from the RPS map of the receiving queue for a given skb.
- * rcu_read_lock must be held on entry.
+ * skb_calculate_flow: calculate a flow hash based on src/dst addresses
+ * and src/dst port numbers. On success, returns a hash number (> 0),
+ * otherwise -1.
*/
-static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
- struct rps_dev_flow **rflowp)
+int skb_calculate_flow(struct net_device *dev, struct sk_buff *skb)
{
+ int hash = skb->rxhash;
struct ipv6hdr *ip6;
struct iphdr *ip;
- struct netdev_rx_queue *rxqueue;
- struct rps_map *map;
- struct rps_dev_flow_table *flow_table;
- struct rps_sock_flow_table *sock_flow_table;
- int cpu = -1;
u8 ip_proto;
- u16 tcpu;
u32 addr1, addr2, ihl;
union {
u32 v32;
u16 v16[2];
} ports;
- if (skb_rx_queue_recorded(skb)) {
- u16 index = skb_get_rx_queue(skb);
- if (unlikely(index >= dev->num_rx_queues)) {
- WARN_ONCE(dev->num_rx_queues > 1, "%s received packet "
- "on queue %u, but number of RX queues is %u\n",
- dev->name, index, dev->num_rx_queues);
- goto done;
- }
- rxqueue = dev->_rx + index;
- } else
- rxqueue = dev->_rx;
-
- if (!rxqueue->rps_map && !rxqueue->rps_flow_table)
- goto done;
-
- if (skb->rxhash)
+ if (hash)
goto got_hash; /* Skip hash computation on packet header */
switch (skb->protocol) {
@@ -2334,6 +2307,7 @@ static int get_rps_cpu(struct net_device
default:
goto done;
}
+
switch (ip_proto) {
case IPPROTO_TCP:
case IPPROTO_UDP:
@@ -2356,11 +2330,59 @@ static int get_rps_cpu(struct net_device
/* get a consistent hash (same value on both flow directions) */
if (addr2 < addr1)
swap(addr1, addr2);
- skb->rxhash = jhash_3words(addr1, addr2, ports.v32, hashrnd);
- if (!skb->rxhash)
- skb->rxhash = 1;
+
+ hash = jhash_3words(addr1, addr2, ports.v32, hashrnd);
+ if (!hash)
+ hash = 1;
got_hash:
+ return hash;
+
+done:
+ return -1;
+}
+EXPORT_SYMBOL(skb_calculate_flow);
+
+#ifdef CONFIG_RPS
+
+/* One global table that all flow-based protocols share. */
+struct rps_sock_flow_table *rps_sock_flow_table __read_mostly;
+EXPORT_SYMBOL(rps_sock_flow_table);
+
+/*
+ * get_rps_cpu is called from netif_receive_skb and returns the target
+ * CPU from the RPS map of the receiving queue for a given skb.
+ * rcu_read_lock must be held on entry.
+ */
+static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
+ struct rps_dev_flow **rflowp)
+{
+ struct netdev_rx_queue *rxqueue;
+ struct rps_map *map;
+ struct rps_dev_flow_table *flow_table;
+ struct rps_sock_flow_table *sock_flow_table;
+ int cpu = -1;
+ u16 tcpu;
+
+ if (skb_rx_queue_recorded(skb)) {
+ u16 index = skb_get_rx_queue(skb);
+ if (unlikely(index >= dev->num_rx_queues)) {
+ WARN_ONCE(dev->num_rx_queues > 1, "%s received packet "
+ "on queue %u, but number of RX queues is %u\n",
+ dev->name, index, dev->num_rx_queues);
+ goto done;
+ }
+ rxqueue = dev->_rx + index;
+ } else
+ rxqueue = dev->_rx;
+
+ if (!rxqueue->rps_map && !rxqueue->rps_flow_table)
+ goto done;
+
+ skb->rxhash = skb_calculate_flow(dev, skb);
+ if (skb->rxhash < 0)
+ goto done;
+
flow_table = rcu_dereference(rxqueue->rps_flow_table);
sock_flow_table = rcu_dereference(rps_sock_flow_table);
if (flow_table && sock_flow_table) {
next reply other threads:[~2010-08-02 14:33 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-02 14:33 Krishna Kumar [this message]
2010-08-02 14:33 ` [PATCH v2 2/2] macvtap: Implement multiqueue macvtap driver Krishna Kumar
2010-08-02 15:52 ` Arnd Bergmann
2010-08-02 16:28 ` Krishna Kumar2
2010-08-02 16:34 ` Arnd Bergmann
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