Re: [dpdk-dev] [PATCH 2/2] doc: update programmers guide for uio_pci_generic

[Bruce Richardson <bruce.richardson@intel.com>]

On Wed, Feb 25, 2015 at 12:19:10PM +0000, Iremonger, Bernard wrote:
> 
> 
> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Bruce Richardson
> > Sent: Tuesday, February 24, 2015 4:28 PM
> > To: dev@dpdk.org
> > Subject: [dpdk-dev] [PATCH 2/2] doc: update programmers guide for uio_pci_generic
> > 
> > Since DPDK now has support for the in-tree uio_pci_generic driver, update the programmers guide
> > document to reference this module, and to use it in preference to the igb_uio driver, which is DPDK-
> > specific.
> > 
> > Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> > ---
> >  doc/guides/prog_guide/env_abstraction_layer.rst                  | 8 ++++----
> >  doc/guides/prog_guide/intel_dpdk_xen_based_packet_switch_sol.rst | 6 +++---
> >  doc/guides/prog_guide/kernel_nic_interface.rst                   | 2 +-
> >  doc/guides/prog_guide/poll_mode_drv_emulated_virtio_nic.rst      | 8 ++++----
> >  doc/guides/prog_guide/poll_mode_drv_paravirtual_vmxnets_nic.rst  | 2 +-
> >  5 files changed, 13 insertions(+), 13 deletions(-)
> > 
> > diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst
> > b/doc/guides/prog_guide/env_abstraction_layer.rst
> > index 231e266..b5321c3 100644
> > --- a/doc/guides/prog_guide/env_abstraction_layer.rst
> > +++ b/doc/guides/prog_guide/env_abstraction_layer.rst
> > @@ -66,7 +66,7 @@ EAL in a Linux-userland Execution Environment
> >  ---------------------------------------------
> > 
> >  In a Linux user space environment, the DPDK application runs as a user-space application using the
> > pthread library.
> > -PCI information about devices and address space is discovered through the /sys kernel interface and
> > through a module called igb_uio.
> > +PCI information about devices and address space is discovered through the /sys kernel interface and
> > through kernel modules such as uio_pci_generic, or igb_uio.
> >  Refer to the UIO: User-space drivers documentation in the Linux kernel. This memory is mmap'd in
> > the application.
> > 
> >  The EAL performs physical memory allocation using mmap() in hugetlbfs (using huge page sizes to
> > increase performance).
> > @@ -134,10 +134,10 @@ PCI Access
> >  ~~~~~~~~~~
> > 
> >  The EAL uses the /sys/bus/pci utilities provided by the kernel to scan the content on the PCI bus.
> > -
> > -To access PCI memory, a kernel module called igb_uio provides a /dev/uioX device file
> > +To access PCI memory, a kernel module called uio_pci_generic provides a
> > +/dev/uioX device file and resource files in /sys
> >  that can be mmap'd to obtain access to PCI address space from the application.
> > -It uses the uio kernel feature (userland driver).
> > +The DPDK-specific igb_uio module can also be used for this. Both drivers use the uio kernel feature
> > (userland driver).
> > 
> >  Per-lcore and Shared Variables
> >  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > diff --git a/doc/guides/prog_guide/intel_dpdk_xen_based_packet_switch_sol.rst
> > b/doc/guides/prog_guide/intel_dpdk_xen_based_packet_switch_sol.rst
> > index 1f1e04f..a0dd959 100644
> > --- a/doc/guides/prog_guide/intel_dpdk_xen_based_packet_switch_sol.rst
> > +++ b/doc/guides/prog_guide/intel_dpdk_xen_based_packet_switch_sol.rst
> > @@ -306,12 +306,12 @@ Building and Running the Switching Backend
> >          Refer to the *DPDK Getting Started Guide* for more information on memory management in the
> > DPDK.
> >          In the above command, 4 GB memory is reserved (2048 of 2 MB pages) for DPDK.
> > 
> > -#.  Load igb_uio and bind one Intel NIC controller to igb_uio:
> > +#.  Load uio_pci_generic and bind one Intel NIC controller to it:
> > 
> >      .. code-block:: console
> > 
> > -        insmod x86_64-native-linuxapp-gcc/kmod/igb_uio.ko
> > -        python tools/dpdk_nic_bind.py -b igb_uio 0000:09:00:00.0
> 
> 
> Hi Bruce,
> 
> Should the information about igb_uio be retained alongside the new information about uio_pci_generic?
>
While the answer may not be as clear-cut as with the GSG, why would be bother
covering both here. We already ignore VFIO in these examples.

/Bruce