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Date: Fri, 6 Mar 2015 17:33:58 +0100
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From: David Marchand <david.marchand@6wind.com>
To: Stephen Hemminger <stephen@networkplumber.org>
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Subject: Re: [dpdk-dev] [PATCH 1/2] virtio: initialize iopl when device is
	initialized
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Hello Stephen,

On Fri, Mar 6, 2015 at 5:20 PM, Stephen Hemminger <
stephen@networkplumber.org> wrote:

> The issue is that virtio has no place it can do iopl() and have the IRQ
> thread
> work. It only shows up on real code where application is daemon, not in a
> toy
> demo or test application.
>
> Right now:
>     gcc start
>        rte_virtio_pmd_init
>           iopl
>     main
>         daemon
>             fork
>                 fork
>                   Process is now child of init not original process
>
>                   rte_eal_init
>                      fork (pthread) for irq thread
>                                                        irq thread
>                                                         (no iopl permssion)
>                   program start
>                   rte_pmd_virtio_configure
>
>
> So the only place where iopl() can be done in the proper context
> so that the IRQ (and other helper threads in future) have the correct
> permissions is in eal_init.
>

Is eth_virtio_dev_init() not a better place rather than eal ?

I prefer avoiding #ifdef pmd in eal.


-- 
David Marchand