On Mon, 08 Oct 2012 15:10:35 -0400 (EDT)
David Miller [off-list ref] wrote:

From: Stephen Hemminger <redacted>
Date: Mon, 8 Oct 2012 11:58:35 -0700

quoted

Limit the latency of pending GRO in NAPI processing to 2*HZ.
When the system is under heavy network load, NAPI will go into
poll mode via soft irq, and only stay in the loop for
two jiffies. If this occurs, process the GRO pending list
to make sure and not delay outstanding TCP frames for too long.

Rearrange the exit path to get rid of unnecessary goto logic.

Signed-off-by: Stephen Hemminger <redacted>

Did you see Eric's patch I just applied which limits it to 1ms?

Think this is a different problem.
After leaving softirq, it may be a long time until
ksoftirqd is run which is a different problem.