Re: RTE Ring removing

["Rogers, Gerald" <gerald.rogers-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

Venky,

This also applies to mbuf pools.  Inside of the openvswitch.org patches we
allocate mbuf pools for a port, but we are unable to free them back when
the port is removed.

One other request (maybe it is there, and I¹m unaware), is the ability to
dynamically add / remove a physical port to DPDK.  Basically we should be
able to reassign on the fly a port from the kernel to DPDK, and vice versa
(of course with the caveat that all structures be released in both
environments and a port reinitialized).

Gerald

On 5/7/14, 7:01 AM, "Venkatesan, Venky" <venky.venkatesan-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> wrote:

>Olivier, 
>
>We should look at how to make the memseg capable of doing alloc/free
>(including re-assembly of fragments) after the 1.7 release. Is that
>something you are considering doing (or are there any other DPDKers
>considering this), or should I look at putting together a patch for that?
>
>Regards, 
>-Venky
>
>-----Original Message-----
>From: dev [mailto:dev-bounces-VfR2kkLFssw@public.gmane.org] On Behalf Of Olivier MATZ
>Sent: Wednesday, May 07, 2014 4:39 AM
>To: Igor Ryzhov; dev-VfR2kkLFssw@public.gmane.org
>Subject: Re: [dpdk-dev] RTE Ring removing
>
>Hi Igor,
>
>On 05/07/2014 09:54 AM, Igor Ryzhov wrote:
>> I noticed that in Memzone realization there is a special global
>> variable "free_memseg" containing pointers on free memory segments.
>> An memzone reserve function just finst the best segment for allocation
>> from this "free_memseg" variable.
>>
>> So I think there is a possibility to unreserve already reserved memory
>> back to "free_memseg", and impossibility of unreserving memory is just
>> because there is no function for that, not because it is impossible in
>> principle.
>> Am I right? Or there are any restrictions?
>
>I think that implementing a freeing of memory segment is feasible, but it
>would require some work to properly merge freed zones to avoid memory
>fragmentation.
>
>Another solution is to allocate/free rings in standard memory (malloc for
>instance) instead of rte_memzones. Let me know if the patches I've just
>sent on the mailing list solves your issue.
>
>By the way, I plan to do the same thing for mempools in the coming weeks
>but there is much more work.
>
>Regards,
>Olivier
>