On Mon, May 08, 2023 at 11:26:59PM +0000, Gilbert Carrillo wrote:
> 
> 
> -----Original Message-----
> From: Bruce Richardson <bruce.richard...@intel.com> 
> Sent: Wednesday, May 3, 2023 11:18 AM
> To: Gilbert Carrillo <gcarri...@ampex.com>
> Cc: dev@dpdk.org
> Subject: Re: DPDK 22.11 Troubleshooting
> 
> On Wed, May 03, 2023 at 04:53:20PM +0000, Gilbert Carrillo wrote:
> > Make static returns an error (see attached).
> > 
> > v/R,
> > Gilbert
> >
> 
> To help investigate this issue, can you perhaps include the text of the full 
> build output when you run "make static". On my system I see libelf listed on 
> the linker flags when I run "make static", and things link properly. I'm 
> wondering how my setup may differ from yours.
> 
> /Bruce
>  
> > -----Original Message-----
> > From: Bruce Richardson <bruce.richard...@intel.com>
> > Sent: Wednesday, May 3, 2023 10:35 AM
> > To: Gilbert Carrillo <gcarri...@ampex.com>
> > Cc: dev@dpdk.org
> > Subject: Re: DPDK 22.11 Troubleshooting
> > 
> > On Wed, May 03, 2023 at 04:22:05PM +0000, Gilbert Carrillo wrote:
> > > Hi Bruce,
> > > 
> > > Thank you for the response.
> > > 
> > > There is no errors when I run the makefile, however I do see a difference 
> > > in the programs. I don't believe the makefile is linking all the 
> > > libraries together as intended.
> > > 
> > > For example, when I run the ethtool sample program and compile it using 
> > > meson, it works fine and rte_eth_dev_count_avail() returns the correct 
> > > amount. However, when I compile ethtool with the makefile and run it 
> > > rte_eth_dev_count_avail() returns 0.
> > > 
> > 
> > Note that by default the meson build will statically link the examples, 
> > while the makefile will dynamically load the drivers at runtime. That may 
> > explain the difference. Can you try building and running using "make 
> > static" rather than just "make".
> > 
> > /Bruce
> 
> Bruce,
> 
> I had multiple versions of DPDK installed and I was linking the wrong one. I 
> was able to compile my application with CMAKE successfully.
> 
> I had one last quick question. I am trying to achieve zero copy DMA from my 
> FPGA to my external buffer. Is this possible? I saw methods such as attaching 
> an mbuf to the external buffer? But I wasn't sure if this was truly zero copy.
> 
Attaching an mbuf to an external buffer would not involve any copy of the
data itself, so should be zero-copy. Each mbuf header contains a buffer
pointer, which normally points just to the end of the header structure, but
which can point to any other location in memory.

/Bruce

Reply via email to