Re: [dpdk-dev] [RFC v9] /net: memory interface (memif)

["Jakub Grajciar -X (jgrajcia - PANTHEON TECHNOLOGIES at Cisco)" <jgrajcia@cisco.com>]

> -----Original Message-----
> From: Ferruh Yigit <ferruh.yigit@intel.com>
> Sent: Wednesday, May 29, 2019 7:29 PM
> To: Jakub Grajciar -X (jgrajcia - PANTHEON TECHNOLOGIES at Cisco)
> <jgrajcia@cisco.com>; dev@dpdk.org
> Subject: Re: [dpdk-dev] [RFC v9] /net: memory interface (memif)

> > +
> > +.. csv-table:: **Memif configuration options**
> > +   :header: "Option", "Description", "Default", "Valid value"
> > +
> > +   "id=0", "Used to identify peer interface", "0", "uint32_t"
> > +   "role=master", "Set memif role", "slave", "master|slave"
> > +   "bsize=1024", "Size of single packet buffer", "2048", "uint16_t"
> 
> What happens is 'bsize < mbuf size'? I didn't see any check in the code but is
> there any assumption around this?
> Or any assumption that slave and master packet should be same? Or any
> other relation?
> If there is any assumption it may be good to add checks to the code and
> document here.

There is no relation between bsize and mbuf size. Memif driver will consume as many buffers as it needs (chaining them). 

> > +#ifndef _RTE_ETH_MEMIF_H_
> > +#define _RTE_ETH_MEMIF_H_
> > +
> > +#ifndef _GNU_SOURCE
> > +#define _GNU_SOURCE
> > +#endif				/* GNU_SOURCE */
> 
> Why this was required?

_GNU_SOURCE is required by memfd_create().