Re: [PATCH v2 2/3] eal: PCI domain should be 32 bits

[Stephen Hemminger <stephen@networkplumber.org>]

On Thu, 22 Jun 2017 18:05:42 +0200
Thomas Monjalon <thomas@monjalon.net> wrote:

> 22/06/2017 17:56, Stephen Hemminger:
> > In some environments, the PCI domain can be larger than 16 bits.
> > For example, a PCI device passed through in Azure gets a synthetic domain
> > id  which is internally generated based on GUID. The PCI standard does
> > not restrict domain to be 16 bits.
> > 
> > This change breaks ABI for API's that expose PCI address structure.
> > 
> > Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
> > ---  
> [...]
> > --- a/lib/librte_eal/common/include/rte_pci.h
> > +++ b/lib/librte_eal/common/include/rte_pci.h
> > @@ -63,7 +63,7 @@ const char *pci_get_sysfs_path(void);
> >  
> >  /** Formatting string for PCI device identifier: Ex: 0000:00:01.0 */
> >  #define PCI_PRI_FMT "%.4" PRIx16 ":%.2" PRIx8 ":%.2" PRIx8 ".%" PRIx8
> > -#define PCI_PRI_STR_SIZE sizeof("XXXX:XX:XX.X")
> > +#define PCI_PRI_STR_SIZE sizeof("XXXXXXXX:XX:XX.X")  
> 
> I think you need to change PCI_PRI_FMT accordingly.

No. I don't want all outputs to have extra leading zeros on other platforms
The existing format works:

Example:
--- cut here ---

struct rte_pci_addr {
	uint32_t domain;                /**< Device domain */
	uint8_t bus;                    /**< Device bus */
	uint8_t devid;                  /**< Device ID */
	uint8_t function;               /**< Device function. */
};

#define PCI_PRI_FMT "%.4" PRIx16 ":%.2" PRIx8 ":%.2" PRIx8 ".%" PRIx8

int main(void)
{
	struct rte_pci_addr pci_addr = { 0, 5, 0, 0 };

	printf(PCI_PRI_FMT "\n",
		       pci_addr.domain,
		       pci_addr.bus, pci_addr.devid,
		       pci_addr.function);

	pci_addr.domain = 0xdeadbeef;
	
	printf(PCI_PRI_FMT "\n",
		       pci_addr.domain,
		       pci_addr.bus, pci_addr.devid,
		       pci_addr.function);
	
	return 0;
}

--- output ---
0000:05:00.0
deadbeef:05:00.0