net: fix softnet_stat

Per cpu variable softnet_data.total was shared between IRQ and SoftIRQ context
without any protection. And enqueue_to_backlog should update the netdev_rx_stat
of the target CPU.

This patch renames softnet_data.total to softnet_data.processed: the number of
packets processed in uppper levels(IP stacks).

softnet_stat data is moved into softnet_data.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
----
 include/linux/netdevice.h |   17 +++++++----------
 net/core/dev.c            |   26 ++++++++++++--------------
 net/sched/sch_generic.c   |    2 +-
 3 files changed, 20 insertions(+), 25 deletions(-)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Changli Gao 2010-05-02 05:42:16 +00:00 committed by David S. Miller
parent 7ef527377b
commit dee42870a4
3 changed files with 20 additions and 25 deletions

View File

@ -218,16 +218,6 @@ struct neighbour;
struct neigh_parms;
struct sk_buff;
struct netif_rx_stats {
unsigned total;
unsigned dropped;
unsigned time_squeeze;
unsigned cpu_collision;
unsigned received_rps;
};
DECLARE_PER_CPU(struct netif_rx_stats, netdev_rx_stat);
struct netdev_hw_addr {
struct list_head list;
unsigned char addr[MAX_ADDR_LEN];
@ -1390,6 +1380,12 @@ struct softnet_data {
struct sk_buff *completion_queue;
struct sk_buff_head process_queue;
/* stats */
unsigned processed;
unsigned time_squeeze;
unsigned cpu_collision;
unsigned received_rps;
#ifdef CONFIG_RPS
struct softnet_data *rps_ipi_list;
@ -1399,6 +1395,7 @@ struct softnet_data {
unsigned int cpu;
unsigned int input_queue_head;
#endif
unsigned dropped;
struct sk_buff_head input_pkt_queue;
struct napi_struct backlog;
};

View File

@ -2205,8 +2205,6 @@ int netdev_max_backlog __read_mostly = 1000;
int netdev_budget __read_mostly = 300;
int weight_p __read_mostly = 64; /* old backlog weight */
DEFINE_PER_CPU(struct netif_rx_stats, netdev_rx_stat) = { 0, };
#ifdef CONFIG_RPS
/* One global table that all flow-based protocols share. */
@ -2366,7 +2364,7 @@ static void rps_trigger_softirq(void *data)
struct softnet_data *sd = data;
__napi_schedule(&sd->backlog);
__get_cpu_var(netdev_rx_stat).received_rps++;
sd->received_rps++;
}
#endif /* CONFIG_RPS */
@ -2405,7 +2403,6 @@ static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
sd = &per_cpu(softnet_data, cpu);
local_irq_save(flags);
__get_cpu_var(netdev_rx_stat).total++;
rps_lock(sd);
if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) {
@ -2429,9 +2426,9 @@ static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
goto enqueue;
}
sd->dropped++;
rps_unlock(sd);
__get_cpu_var(netdev_rx_stat).dropped++;
local_irq_restore(flags);
kfree_skb(skb);
@ -2806,7 +2803,7 @@ static int __netif_receive_skb(struct sk_buff *skb)
skb->dev = master;
}
__get_cpu_var(netdev_rx_stat).total++;
__get_cpu_var(softnet_data).processed++;
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
@ -3490,7 +3487,7 @@ static void net_rx_action(struct softirq_action *h)
return;
softnet_break:
__get_cpu_var(netdev_rx_stat).time_squeeze++;
sd->time_squeeze++;
__raise_softirq_irqoff(NET_RX_SOFTIRQ);
goto out;
}
@ -3691,17 +3688,17 @@ static int dev_seq_show(struct seq_file *seq, void *v)
return 0;
}
static struct netif_rx_stats *softnet_get_online(loff_t *pos)
static struct softnet_data *softnet_get_online(loff_t *pos)
{
struct netif_rx_stats *rc = NULL;
struct softnet_data *sd = NULL;
while (*pos < nr_cpu_ids)
if (cpu_online(*pos)) {
rc = &per_cpu(netdev_rx_stat, *pos);
sd = &per_cpu(softnet_data, *pos);
break;
} else
++*pos;
return rc;
return sd;
}
static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
@ -3721,12 +3718,12 @@ static void softnet_seq_stop(struct seq_file *seq, void *v)
static int softnet_seq_show(struct seq_file *seq, void *v)
{
struct netif_rx_stats *s = v;
struct softnet_data *sd = v;
seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
s->total, s->dropped, s->time_squeeze, 0,
sd->processed, sd->dropped, sd->time_squeeze, 0,
0, 0, 0, 0, /* was fastroute */
s->cpu_collision, s->received_rps);
sd->cpu_collision, sd->received_rps);
return 0;
}
@ -5869,6 +5866,7 @@ static int __init net_dev_init(void)
for_each_possible_cpu(i) {
struct softnet_data *sd = &per_cpu(softnet_data, i);
memset(sd, 0, sizeof(*sd));
skb_queue_head_init(&sd->input_pkt_queue);
skb_queue_head_init(&sd->process_queue);
sd->completion_queue = NULL;

View File

@ -94,7 +94,7 @@ static inline int handle_dev_cpu_collision(struct sk_buff *skb,
* Another cpu is holding lock, requeue & delay xmits for
* some time.
*/
__get_cpu_var(netdev_rx_stat).cpu_collision++;
__get_cpu_var(softnet_data).cpu_collision++;
ret = dev_requeue_skb(skb, q);
}