static struct hlist_head *dev_table;
#define VPORT_HASH_BUCKETS 1024
-/* We limit the number of times that we pass through vport_send() to
- * avoid blowing out the stack in the event that we have a loop. There is
- * a separate counter for each CPU for both interrupt and non-interrupt
- * context in order to keep the limit deterministic for a given packet. */
-struct percpu_loop_counter {
- int count[2];
-};
-
-static DEFINE_PER_CPU(struct percpu_loop_counter, vport_loop_counter);
-#define VPORT_MAX_LOOPS 5
-
/* Both RTNL lock and vport_mutex need to be held when updating dev_table.
*
* If you use vport_locate and then perform some operations, you need to hold
for_each_possible_cpu(i) {
const struct vport_percpu_stats *percpu_stats;
+ struct vport_percpu_stats local_stats;
+ unsigned seqcount;
percpu_stats = per_cpu_ptr(vport->percpu_stats, i);
- stats->rx_bytes += percpu_stats->rx_bytes;
- stats->rx_packets += percpu_stats->rx_packets;
- stats->tx_bytes += percpu_stats->tx_bytes;
- stats->tx_packets += percpu_stats->tx_packets;
+
+ do {
+ seqcount = read_seqcount_begin(&percpu_stats->seqlock);
+ local_stats = *percpu_stats;
+ } while (read_seqcount_retry(&percpu_stats->seqlock, seqcount));
+
+ stats->rx_bytes += local_stats.rx_bytes;
+ stats->rx_packets += local_stats.rx_packets;
+ stats->tx_bytes += local_stats.tx_bytes;
+ stats->tx_packets += local_stats.tx_packets;
}
err = 0;
struct vport_percpu_stats *stats;
local_bh_disable();
-
stats = per_cpu_ptr(vport->percpu_stats, smp_processor_id());
+
+ write_seqcount_begin(&stats->seqlock);
stats->rx_packets++;
stats->rx_bytes += skb->len;
+ write_seqcount_end(&stats->seqlock);
local_bh_enable();
}
*/
int vport_send(struct vport *vport, struct sk_buff *skb)
{
- int *loop_count;
int mtu;
int sent;
- loop_count = &get_cpu_var(vport_loop_counter).count[!!in_interrupt()];
- (*loop_count)++;
-
- if (unlikely(*loop_count > VPORT_MAX_LOOPS)) {
- if (net_ratelimit())
- printk(KERN_WARNING "%s: dropping packet that has looped more than %d times\n",
- dp_name(vport_get_dp_port(vport)->dp), VPORT_MAX_LOOPS);
- goto error;
- }
-
mtu = vport_get_mtu(vport);
if (unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) {
if (net_ratelimit())
struct vport_percpu_stats *stats;
local_bh_disable();
-
stats = per_cpu_ptr(vport->percpu_stats, smp_processor_id());
+
+ write_seqcount_begin(&stats->seqlock);
stats->tx_packets++;
stats->tx_bytes += sent;
+ write_seqcount_end(&stats->seqlock);
local_bh_enable();
}
- goto out;
+ return sent;
error:
- sent = 0;
kfree_skb(skb);
vport_record_error(vport, VPORT_E_TX_DROPPED);
-out:
- (*loop_count)--;
- put_cpu_var(vport_loop_counter);
-
- return sent;
+ return 0;
}
/**