Re: [dpdk-dev] [PATCH 1/2] usertools/devbind: add error on forgetting to specify driver

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

On 24-Jul-19 5:29 PM, Stephen Hemminger wrote:
> On Wed, 24 Jul 2019 16:34:43 +0100
> Anatoly Burakov <anatoly.burakov@intel.com> wrote:
> 
>> A common user error is to forget driver to which the PCI devices should
>> be bound to. Currently, the error message in this case looks unhelpful
>> misleading and indecipherable to anyone but people who know how devbind
>> works.
>>
>> Fix this by checking if the driver string is actually a valid device
>> string. If it is, we assume that the user has just forgot to specify the
>> driver, and display appropriate error. We also assume that no one will
>> name their driver in a format that looks like a PCI address, but that
>> seems like a reasonable assumption to make.
>>
>> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
>> ---
>>   usertools/dpdk-devbind.py | 33 ++++++++++++++++++++++++++++-----
>>   1 file changed, 28 insertions(+), 5 deletions(-)
>>
>> diff --git a/usertools/dpdk-devbind.py b/usertools/dpdk-devbind.py
>> index 542ecffcc..f7c4c6434 100755
>> --- a/usertools/dpdk-devbind.py
>> +++ b/usertools/dpdk-devbind.py
>> @@ -342,9 +342,8 @@ def dev_id_from_dev_name(dev_name):
>>               if dev_name in devices[d]["Interface"].split(","):
>>                   return devices[d]["Slot"]
>>       # if nothing else matches - error
>> -    print("Unknown device: %s. "
>> -          "Please specify device in \"bus:slot.func\" format" % dev_name)
>> -    sys.exit(1)
>> +    raise ValueError("Unknown device: %s. "
>> +	    "Please specify device in \"bus:slot.func\" format" % dev_name)
>>   
>>   
>>   def unbind_one(dev_id, force):
>> @@ -493,7 +492,12 @@ def unbind_all(dev_list, force=False):
>>                       unbind_one(devices[d]["Slot"], force)
>>           return
>>   
>> -    dev_list = map(dev_id_from_dev_name, dev_list)
>> +    try:
>> +        dev_list = map(dev_id_from_dev_name, dev_list)
>> +    except ValueError as ex:
>> +        print(ex)
>> +        sys.exit(1)
>> +
>>       for d in dev_list:
>>           unbind_one(d, force)
>>   
>> @@ -502,7 +506,26 @@ def bind_all(dev_list, driver, force=False):
>>       """Bind method, takes a list of device locations"""
>>       global devices
>>   
>> -    dev_list = map(dev_id_from_dev_name, dev_list)
>> +    # a common user error is to forget to specify the driver the devices need to
>> +    # be bound to. check if the driver is a valid device, and if it is, show
>> +    # a meaningful error.
>> +    try:
>> +        dev_id_from_dev_name(driver)
>> +        # if we've made it this far, this means that the "driver" was a valid
>> +        # device string, so it's probably not a valid driver name.
>> +        print("ERROR: Driver '%s' does not look like a valid driver. "
>> +              "Did you forget to specify the driver to bind devices to?" %
>> +              driver)
>> +        sys.exit(1)
>> +    except ValueError:
>> +        # driver generated error - it's not a valid device ID, so all is well
>> +        pass
>> +
>> +    try:
>> +        dev_list = map(dev_id_from_dev_name, dev_list)
>> +    except ValueError as ex:
>> +        print(ex)
>> +        sys.exit(1)
>>   
>>       for d in dev_list:
>>           bind_one(d, driver, force)
> 
> It would be better print error messages to stderr.
> If you call sys.exit() with a string it will do that.
> 

Will fix in v2.

-- 
Thanks,
Anatoly