[dpdk-dev] [PATCH v2 05/15] pci: use scan_mode configuration

[Ferruh Yigit]

On 7/14/2017 10:12 PM, Jan Blunck wrote:
> When scanning/probing devices the bus doesn't need to look at the
> devargs->type field: if the bus is in blacklist probing mode and there is
> no devargs found for the device it is white-listed. Therefore it is enough
> to let the bus check for the scan_mode.
> 
> Signed-off-by: Jan Blunck <jblunck at infradead.org>
> ---
>  lib/librte_eal/common/eal_common_pci.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/lib/librte_eal/common/eal_common_pci.c b/lib/librte_eal/common/eal_common_pci.c
> index 72fcc35c2..fb0e29ac4 100644
> --- a/lib/librte_eal/common/eal_common_pci.c
> +++ b/lib/librte_eal/common/eal_common_pci.c
> @@ -197,8 +197,7 @@ rte_pci_probe_one_driver(struct rte_pci_driver *dr,
>  
>  	/* no initialization when blacklisted, return without error */
>  	if (dev->device.devargs != NULL &&
> -		dev->device.devargs->type ==
> -			RTE_DEVTYPE_BLACKLISTED_PCI) {
> +		rte_pci_bus.bus.conf.scan_mode == RTE_BUS_SCAN_BLACKLIST) {

If eal blacklist command issued (-b), even for one device, bus scan_mode
set to RTE_BUS_SCAN_BLACKLIST. Only devices provided with -b should be
blacklisted, all other devices in the bus should be probed.

If check done based on "scan_mode", this will blacklist all devices in
the bus, unless I am missing something.

I see this is to remove "devargs->type" but I don't think so this can be
replaced with "conf.scan_mode" check.

And while thinking about this, I wonder what "scan_mode" really mean?
and where it is used/useful?

>  		RTE_LOG(INFO, EAL, "  Device is blacklisted, not"
>  			" initializing\n");
>  		return 1;
> @@ -404,8 +403,7 @@ rte_pci_probe(void)
>  		/* probe all or only whitelisted devices */
>  		if (probe_all)
>  			ret = pci_probe_all_drivers(dev);
> -		else if (devargs != NULL &&
> -			devargs->type == RTE_DEVTYPE_WHITELISTED_PCI)
> +		else if (devargs != NULL)

if "probe_all" is not set, this means "scan_mode" is WHITELIST. And only
physical devices white-listed will have devargs, so this check looks OK,
but I believe this requires some comment, otherwise this is not clear.

Also why not check blacklist here?

>  			ret = pci_probe_all_drivers(dev);
>  		if (ret < 0) {
>  			RTE_LOG(ERR, EAL, "Requested device " PCI_PRI_FMT
>