[dpdk-dev] [PATCH v1 1/4] net/iavf: stop the PCI probe in DCF mode

[Ye Xiaolong]

On 03/10, Wang, Haiyue wrote:
>> -----Original Message-----
>> From: Ye, Xiaolong <xiaolong.ye at intel.com>
>> Sent: Monday, March 9, 2020 23:38
>> To: Wang, Haiyue <haiyue.wang at intel.com>
>> Cc: dev at dpdk.org; Zhang, Qi Z <qi.z.zhang at intel.com>; Yang, Qiming <qiming.yang at intel.com>; Xing,
>> Beilei <beilei.xing at intel.com>; Zhao1, Wei <wei.zhao1 at intel.com>
>> Subject: Re: [PATCH v1 1/4] net/iavf: stop the PCI probe in DCF mode
>> 
>> On 03/09, Haiyue Wang wrote:
>> >A new DCF PMD will be introduced, which runs on Intel VF hardware, and
>> >it is a pure software design to control the advance functionality (such
>> >as switch, ACL) for rest of the VFs.
>> >
>> >So if the DCF (Device Config Function) mode is specified by the devarg
>> >'cap=dcf', then it will stop the PCI probe in the iavf PMD.
>> >
>> >Signed-off-by: Haiyue Wang <haiyue.wang at intel.com>
>> >---
>> > drivers/net/iavf/iavf_ethdev.c | 41 ++++++++++++++++++++++++++++++++++
>> > 1 file changed, 41 insertions(+)
>> >
>> >diff --git a/drivers/net/iavf/iavf_ethdev.c b/drivers/net/iavf/iavf_ethdev.c
>> >index 34913f9c4..8ff26c0e7 100644
>> >--- a/drivers/net/iavf/iavf_ethdev.c
>> >+++ b/drivers/net/iavf/iavf_ethdev.c
>> >@@ -1416,9 +1416,49 @@ iavf_dev_uninit(struct rte_eth_dev *dev)
>> > 	return 0;
>> > }
>> >
>> >+static int
>> >+handle_dcf_arg(__rte_unused const char *key, const char *value,
>> >+	       __rte_unused void *arg)
>> >+{
>> >+	bool *dcf = arg;
>> >+
>> >+	if (arg == NULL || value == NULL)
>> >+		return -EINVAL;
>> >+
>> >+	if (strcmp(value, "dcf") == 0)
>> >+		*dcf = true;
>> >+	else
>> >+		*dcf = false;
>> >+
>> >+	return 0;
>> >+}
>> >+
>> >+static bool
>> >+check_cap_dcf_enable(struct rte_devargs *devargs)
>> >+{
>> >+	struct rte_kvargs *kvlist;
>> >+	bool enable = false;
>> >+
>> >+	if (devargs == NULL)
>> >+		return false;
>> >+
>> >+	kvlist = rte_kvargs_parse(devargs->args, NULL);
>> >+	if (kvlist == NULL)
>> >+		return false;
>> >+
>> >+	rte_kvargs_process(kvlist, "cap", handle_dcf_arg, &enable);
>> 
>> Need error handling for failure case.
>>   
>
>We just need the 'cap=dcf' to check whether it is true, by default
>'enable=false' can handle all the cases. ;-)
>

Yes, from function point of view, this could work. But it is still good practice
to check the return value of the function.

Thanks,
Xiaolong