Re: [dpdk-dev] [PATCH v2 0/2] fix and improve uio_pci_generic support

[David Marchand <david.marchand@6wind.com>]

On Tue, Feb 24, 2015 at 12:32 PM, Bruce Richardson <
bruce.richardson@intel.com> wrote:

> On Tue, Feb 24, 2015 at 12:23:15PM +0100, David Marchand wrote:
> > Hello Bruce,
> >
> > On Tue, Feb 24, 2015 at 11:53 AM, Bruce Richardson <
> > bruce.richardson@intel.com> wrote:
> >
> > > On Mon, Feb 23, 2015 at 05:02:33PM +0000, Bruce Richardson wrote:
> > > > This patch does some cleanup of the uio mapping code to
> > > > a) fix issue with mmap of PCI bars reported by Tetsuya and confirmed
> > > > by others.
> > > > b) eliminate redundant code and reduce scans of /sys
> > > >
> > > >
> > > > Bruce Richardson (2):
> > > >   eal: mmap uio resources using resourceX files
> > > >   eal: populate uio_maps from pci mem_resources array
> > > >
> > > >  lib/librte_eal/common/include/rte_pci.h    |   2 +-
> > > >  lib/librte_eal/linuxapp/eal/eal_pci_init.h |   1 +
> > > >  lib/librte_eal/linuxapp/eal/eal_pci_uio.c  | 173
> > > +++++++++++------------------
> > > >  lib/librte_eal/linuxapp/eal/eal_pci_vfio.c |   1 +
> > > >  4 files changed, 66 insertions(+), 111 deletions(-)
> > > >
> > > > --
> > > > 2.1.0
> > > >
> > > Given your previous suggestions on the uio_pic_generic code, I'd
> appreciate
> > > any feedback you could provide on this patchset.
> >
> >
> > Well, I only have one pending question on the use of resourceX files
> > instead of /dev/uioX.
> > You rely on sysfs mmap code for pci resources.
> > Is this really equivalent to uio mmap operations ?
>
> uio_pci_generic provides no mappings via /dev/uioX, so the may to mmap the
> bars using uio_pci_generic is via the sysfs. [1]
>
> > If you can ensure me this won't break igb_uio setups, then these patches
> > are ok for me.
>
> Since igb_uio is based on the same uio_pci_generic framework, what works
> for
> uio_pci_generic should work for igb_uio also - and testing indicates that
> this
> works. Danny could perhaps provide better insights than I can into any
> guarantees
> as to not breaking things, but I've tested this on a couple of platforms
> with
> 1G and 10G NICs using both igb_uio and uio_pci_generic, both individually
> and
> in combination. I've also verified multiprocess support and done a quick
> sanity
> test with 32-bit. Everything seems ok in testing thus far.
>

Ok, noted.
I am looking at your v3.

-- 
David Marchand