Re: [dpdk-dev] [PATCH] eal: fix compilation without VFIO

[Thomas Monjalon <thomas@monjalon.net>]

13/04/2018 15:37, Burakov, Anatoly:
> On 13-Apr-18 2:08 PM, Thomas Monjalon wrote:
> > 13/04/2018 11:11, Burakov, Anatoly:
> >> On 13-Apr-18 12:39 AM, Thomas Monjalon wrote:
> >>> 12/04/2018 16:13, Burakov, Anatoly:
> >>>> On 12-Apr-18 2:34 PM, Shahaf Shuler wrote:
> >>>>> a compilation error occurred when compiling with CONFIG_RTE_EAL_VFIO=n
> >>>>>
> >>>>> == Build lib/librte_eal/linuxapp/eal
> >>>>>      CC eal_vfio.o
> >>>>> /download/dpdk/lib/librte_eal/linuxapp/eal/eal_vfio.c:1535:1: error: no
> >>>>> previous prototype for 'rte_vfio_dma_map' [-Werror=missing-prototypes]
> >>>>>     rte_vfio_dma_map(uint64_t __rte_unused vaddr, __rte_unused uint64_t
> >>>>> iova,
> >>>>>     ^
> >>>>> /download/dpdk/lib/librte_eal/linuxapp/eal/eal_vfio.c:1542:1: error: no
> >>>>> previous prototype for 'rte_vfio_dma_unmap' [-Werror=missing-prototypes]
> >>>>>     rte_vfio_dma_unmap(uint64_t __rte_unused vaddr, uint64_t __rte_unused
> >>>>> iova,
> >>>>>     ^
> >>>>>
> >>>>> As there is no use for those dummy functions without VFIO removing them
> >>>>> completely.
> >>>>
> >>>> These functions are part of public API, like rest of functions in this
> >>>> header. They're in the map file. Should we perhaps go the BSD way and
> >>>> provide EAL with dummy prototypes as well? See bsdapp/eal/eal.c:763 onwards.
> >>>
> >>> Why using dummy prototypes?
> >>> Because the prototypes in rte_vfio.h are under #ifdef VFIO_PRESENT ?
> >>> Is it possible to always define the prototypes in rte_vfio.h ?
> >>>
> >>
> >> Well, technically, yes, we could. There is one function that uses a
> >> VFIO-specific struct definition:
> >>
> >> int rte_vfio_setup_device(const char *sysfs_base, const char *dev_addr,
> >> 		int *vfio_dev_fd, struct vfio_device_info *device_info);
> >>
> >> I'm sure we can work around that.
> > 
> > 
> > Removing dummy prototypes need, would be a nicer fix.
> > 
> 
> OK. Shahaf, will you submit a v2 with this, or should i do it? I think 
> it should be just a matter of #ifndef VFIO_PRESENT //define 
> vfio_device_info struct #endif - this should take care of the problem of 
> hiding the function definitions.
> 
> FreeBSD will also need to be adjusted to remove dummy prototypes.

I think you are more familiar with VFIO than any of us.
It is better to let you do, think about the implications and do the tests.
Thanks :)