rte_mbuf - contiguous ?

rte_mbuf - contiguous ?

[Jose Gavine Cueto]

Hi,

Is the rte_mbuf/packet data always map to a contiguous area in memory, and
so if I can do a linear copy of it ?

Cheers,
pepe

-- 
To stop learning is like to stop loving.

Re: rte_mbuf - contiguous ?

[Thomas Monjalon]

Hello,

24/10/2013 09:49, Jose Gavine Cueto :
> Is the rte_mbuf/packet data always map to a contiguous area in memory, and
> so if I can do a linear copy of it ?

No, in scatter/gather case, mbuf can be splitted in non contiguous areas.

-- 
Thomas

Re: rte_mbuf - contiguous ?

[Jose Gavine Cueto]

Thomas,

Thank you for the information.  Because I would like to copy an rte_mbuf to
a memory mapped file for an application.  Is there some dpdk API for this
copy operation (linear/nonlinear) or are these left with the application
developers ?

Thanks,
Pepe


On Thu, Oct 24, 2013 at 4:03 PM, Thomas Monjalon
<thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>wrote:

> Hello,
>
> 24/10/2013 09:49, Jose Gavine Cueto :
> > Is the rte_mbuf/packet data always map to a contiguous area in memory,
> and
> > so if I can do a linear copy of it ?
>
> No, in scatter/gather case, mbuf can be splitted in non contiguous areas.
>
> --
> Thomas
>



-- 
To stop learning is like to stop loving.

Re: rte_mbuf - contiguous ?

[Thomas Monjalon]

24/10/2013 10:09, Jose Gavine Cueto :
> Thank you for the information.  Because I would like to copy an rte_mbuf to
> a memory mapped file for an application.  Is there some dpdk API for this
> copy operation (linear/nonlinear) or are these left with the application
> developers ?

You can have some tips by looking at rte_pktmbuf_is_contiguous:
http://dpdk.org/doc/api/rte__mbuf_8h.html#a511a116ae4822037d4f1fb561aa4ffcf
and rte_pktmbuf_clone:
http://dpdk.org/doc/api/rte__mbuf_8h.html#a1d26cc982f6363cd7492dd70cc5c287c

-- 
Thomas

Re: rte_mbuf - contiguous ?

[Jose Gavine Cueto]

Hi Thomas,

I've read both the rte_pktmbuf_is_contiguous and rte_pktmbuf_clone.  I
think that I can get each mbuf segments and copy them to memory linearly.
 Thanks for the tip.


On Thu, Oct 24, 2013 at 4:32 PM, Thomas Monjalon
<thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>wrote:

> 24/10/2013 10:09, Jose Gavine Cueto :
> > Thank you for the information.  Because I would like to copy an rte_mbuf
> to
> > a memory mapped file for an application.  Is there some dpdk API for this
> > copy operation (linear/nonlinear) or are these left with the application
> > developers ?
>
> You can have some tips by looking at rte_pktmbuf_is_contiguous:
> http://dpdk.org/doc/api/rte__mbuf_8h.html#a511a116ae4822037d4f1fb561aa4ffcf
> and rte_pktmbuf_clone:
> http://dpdk.org/doc/api/rte__mbuf_8h.html#a1d26cc982f6363cd7492dd70cc5c287c
>
> --
> Thomas
>



-- 
To stop learning is like to stop loving.