Commit 7d58e655 authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

net-sysfs: add backlog len and CPU id to softnet data 



Currently the backlog status in not exposed to user-space.
Since long backlogs (or simply not empty ones) can be a
source of noticeable latency, -RT deployments need some way
to inspect it.

Additionally, there isn't a direct match between 'softnet_stat'
lines and the related CPU - sd for offline CPUs are not dumped -
so this patch also includes the CPU id into such entry.

Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c4f084ed

net/core/net-procfs.c

+13 −2
Original line number Diff line number Diff line
@@ -116,6 +116,12 @@ static int dev_seq_show(struct seq_file *seq, void *v) 
	return 0;

}



static u32 softnet_backlog_len(struct softnet_data *sd)

{

	return skb_queue_len_lockless(&sd->input_pkt_queue) +

	       skb_queue_len_lockless(&sd->process_queue);

}



static struct softnet_data *softnet_get_online(loff_t *pos)

{

	struct softnet_data *sd = NULL;
@@ -159,12 +165,17 @@ static int softnet_seq_show(struct seq_file *seq, void *v) 
	rcu_read_unlock();

#endif



	/* the index is the CPU id owing this sd. Since offline CPUs are not

	 * displayed, it would be othrwise not trivial for the user-space

	 * mapping the data a specific CPU

	 */

	seq_printf(seq,

		   "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n",

		   "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n",

		   sd->processed, sd->dropped, sd->time_squeeze, 0,

		   0, 0, 0, 0, /* was fastroute */

		   0,	/* was cpu_collision */

		   sd->received_rps, flow_limit_count);

		   sd->received_rps, flow_limit_count,

		   softnet_backlog_len(sd), (int)seq->index);

	return 0;

}