From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [dpdk-users] Link Status and Interrupts in 2.2.0
Date: Wed, 27 Apr 2016 11:39:37 +0200
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2016-04-25 11:49, martin_curran-gray@keysight.com:
> But if the link was "active" when dpdk and my app starts up,
> then no interrupt is generated, which then means that global
> structure is not filled in

You are describing the case of interrupts enabled but never called.
It has been fixed in DPDK 2.0:
	http://dpdk.org/commit/99610782

But a race condition has been seen if interrupt fires during
rte_eth_dev_start() call. The decision was to remove link update if
interrupt is enabled (DPDK 2.2):
	http://dpdk.org/commit/d5790b03
This "fix" was a bit strange:
- Is it possible to fix the race condition with link_update in the drivers?
- Is it possible to update the link status in dev_start of each driver
without race condition with the interrupt?
- Why calling link_update() from rte_eth_dev_start() in the polling case?

> I saw a submission to the patchwork 7160, dated Sep 24 2015
> but it was marked as not applicable , archived.....

It has been re-submitted and applied (hence the problem):
	http://dpdk.org/patch/8112