Re: [PATCH] igb_uio: fix build for longterm kernel 2.6.32.63

[Thomas Monjalon <thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>]

Hi Jincheng,

2014-10-31 09:54, Jincheng Miao:
> This patch will make RHEL6 build failed.
> 
> The root cause is that RHEL-based kernel is slightly different with 
> upstream kernel.
> It has some functions (pci_num_vf, kstrtoul, etc) which don't exist in 
> upstream longterm kernel.

Yes it seems that the functions are stub-defined in RHEL if CONFIG_PCI_IOV
is not defined.

> For better compatibility, IMHO it is distinguishing RHEL-based kernel 
> and upstream one.

Yes we have to handle the RedHat difference.

> Using macro like:
> ```
> #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \
>      !(defined(RHEL_RELEASE_CODE) && RHEL_RELEASE_CODE >= 
> RHEL_RELEASE_VERSION(6, 3))
> 
> static int pci_num_vf(struct pci_dev *dev)
>   {
> ```
> 
> But this is RHEL-specified fix. For other distros, if they have some 
> problem, we should hack it in the same way.
> 
> Thanks and regards,
> Jincheng Miao
> 
> 
> On 10/30/2014 04:18 PM, Jincheng Miao wrote:
> > There is a logical error in igb_uio/compat.h when define pci_num_vf().
> > Only CONFIG_PCI_IOV enabled, this function could be defined.
> >
> > This patch fix the following error for linux-2.6.32.63:
> > CC [M]  /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.o
> > /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.c: In function ‘show_max_vfs’:
> > /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.c:75: error: implicit declaration of function ‘pci_num_vf’
> >
> > Signed-off-by: Jincheng Miao <jmiao-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> > ---
> >   lib/librte_eal/linuxapp/igb_uio/compat.h |    2 +-
> >   1 files changed, 1 insertions(+), 1 deletions(-)
> >
> > diff --git a/lib/librte_eal/linuxapp/igb_uio/compat.h b/lib/librte_eal/linuxapp/igb_uio/compat.h
> > index 676fa1b..0af0cae 100644
> > --- a/lib/librte_eal/linuxapp/igb_uio/compat.h
> > +++ b/lib/librte_eal/linuxapp/igb_uio/compat.h
> > @@ -21,7 +21,7 @@
> >   #endif
> >   
> >   #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \
> > -	!defined(CONFIG_PCI_IOV)
> > +	defined(CONFIG_PCI_IOV)
> >   
> >   static int pci_num_vf(struct pci_dev *dev)
> >   {