From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Qiu, Michael" <michael.qiu@intel.com>
Subject: Re: [PATCH] eal: add function to check if primary proc
 alive
Date: Thu, 21 Jan 2016 06:14:00 +0000
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To: "Van Haaren, Harry" <harry.van.haaren@intel.com>,
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On 1/20/2016 9:26 PM, Harry van Haaren wrote:=0A=
> This patch adds a new function to the EAL API:=0A=
> int rte_eal_primary_proc_alive(const char *path);=0A=
>=0A=
> The function indicates if a primary process is alive right now.=0A=
> This functionality is implemented by testing for a write-=0A=
> lock on the config file, and the function tests for a lock.=0A=
>=0A=
> The use case for this functionality is that a secondary=0A=
> process can wait until a primary process starts by polling=0A=
> the function and waiting. When the primary is running, the=0A=
> secondary continues to poll to detect if the primary process=0A=
> has quit unexpectedly, the secondary process can detect this.=0A=
>=0A=
> The RTE_MAGIC number is written to the shared config by the=0A=
> primary process, this is the signal to the secondary process=0A=
> that the EAL is set up, and ready to be used. The function=0A=
> rte_eal_mcfg_complete() writes RTE_MAGIC. This has been=0A=
> delayed in the EAL init proceedure, as the PCI probing in=0A=
> the primary process can interfere with the secondary running.=0A=
>=0A=
> Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com>=0A=
> ---=0A=
=0A=
one question:=0A=
=0A=
As we could start up many primaries, how does your secondary process=0A=
work with them?=0A=
=0A=
Thanks,=0A=
Michael=0A=
=0A=