Re: [dpdk-dev] About pmu cycle counter usage in armv8

-Original Message- > Date: Mon, 11 Dec 2017 14:23:54 +0800 > From: Jia He > To: Jerin Jacob > Cc: "dev@dpdk.org" > Subject: Re: About pmu cycle counter usage in armv8 > User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 > Thunderbird/52.5.0 > > Hi Jerin Hi Jia. >

Re: [dpdk-dev] About pmu cycle counter usage in armv8

Hi Jerin Ok And I wonder why you haven't met such problem (all rd_tsc() is 0)in your test platform? Did you use an old kernel (older than v4.5-rc1)? root@aw-host:~/linux# git describe da4e4f18afe0 v4.5-rc1-8-gda4e4f1 Maybe you need to give a warning that, the usage of High-resolution cycle

Re: [dpdk-dev] About pmu cycle counter usage in armv8

-Original Message- > Date: Mon, 11 Dec 2017 13:38:25 +0800 > From: Jia He > To: Jerin Jacob , "dev@dpdk.org" > > Subject: About pmu cycle counter usage in armv8 > User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 > Thunderbird/52.5.0 > > Hi Jerin > > In [1], I me

[dpdk-dev] About pmu cycle counter usage in armv8

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 to