From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jia He <hejianet@gmail.com>
Subject: About pmu cycle counter usage in armv8
Date: Mon, 11 Dec 2017 13:38:25 +0800
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To: Jerin Jacob <jerin.jacob@caviumnetworks.com>, "dev@dpdk.org" <dev@dpdk.org>
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Hi Jerin

In [1], I met a pmu cycle counter problem (all return value is 0) 
occasionally.

And then I submited a patch to kernel maillist, but was rejected by 
maintainer at last [2].

He said:

"We only intend for the in-kernel perf infrastructure to access

pmccntr_el0; nothing else should touch it."

So maybe it is not proper for dpdk to use pmu cycle counter?

[1] http://dpdk.org/ml/archives/dev/2017-November/080998.html

[2]https://lkml.org/lkml/2017/11/16/22

-- 
Cheers,
Jia