diff options
Diffstat (limited to 'net/core/dev.c')
-rw-r--r-- | net/core/dev.c | 48 |
1 files changed, 47 insertions, 1 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 18e9730..7229bc3 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3064,6 +3064,46 @@ static int rps_ipi_queued(struct softnet_data *sd) return 0; } +#ifdef CONFIG_NET_FLOW_LIMIT +int netdev_flow_limit_table_len __read_mostly = (1 << 12); +#endif + +static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) +{ +#ifdef CONFIG_NET_FLOW_LIMIT + struct sd_flow_limit *fl; + struct softnet_data *sd; + unsigned int old_flow, new_flow; + + if (qlen < (netdev_max_backlog >> 1)) + return false; + + sd = &__get_cpu_var(softnet_data); + + rcu_read_lock(); + fl = rcu_dereference(sd->flow_limit); + if (fl) { + new_flow = skb_get_rxhash(skb) & (fl->num_buckets - 1); + old_flow = fl->history[fl->history_head]; + fl->history[fl->history_head] = new_flow; + + fl->history_head++; + fl->history_head &= FLOW_LIMIT_HISTORY - 1; + + if (likely(fl->buckets[old_flow])) + fl->buckets[old_flow]--; + + if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { + fl->count++; + rcu_read_unlock(); + return true; + } + } + rcu_read_unlock(); +#endif + return false; +} + /* * enqueue_to_backlog is called to queue an skb to a per CPU backlog * queue (may be a remote CPU queue). @@ -3073,13 +3113,15 @@ static int enqueue_to_backlog(struct sk_buff *skb, int cpu, { struct softnet_data *sd; unsigned long flags; + unsigned int qlen; sd = &per_cpu(softnet_data, cpu); local_irq_save(flags); rps_lock(sd); - if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) { + qlen = skb_queue_len(&sd->input_pkt_queue); + if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) { if (skb_queue_len(&sd->input_pkt_queue)) { enqueue: __skb_queue_tail(&sd->input_pkt_queue, skb); @@ -6269,6 +6311,10 @@ static int __init net_dev_init(void) sd->backlog.weight = weight_p; sd->backlog.gro_list = NULL; sd->backlog.gro_count = 0; + +#ifdef CONFIG_NET_FLOW_LIMIT + sd->flow_limit = NULL; +#endif } dev_boot_phase = 0; |