[dpdk-dev] [PATCH v8 8/9] ethdev: representor iterator compare complete info

[Xueming(Steven) Li]

>-----Original Message-----
>From: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
>Sent: Tuesday, March 9, 2021 4:20 PM
>To: Xueming(Steven) Li <xuemingl at nvidia.com>
>Cc: dev at dpdk.org; Slava Ovsiienko <viacheslavo at nvidia.com>; Asaf Penso <asafp at nvidia.com>; NBU-Contact-Thomas Monjalon
><thomas at monjalon.net>; Ferruh Yigit <ferruh.yigit at intel.com>; Ray Kinsella <mdr at ashroe.eu>; Neil Horman
><nhorman at tuxdriver.com>
>Subject: Re: [PATCH v8 8/9] ethdev: representor iterator compare complete info
>
>On 3/4/21 5:30 PM, Xueming Li wrote:
>> The NIC can have multiple PCIe links and can be attached to multiple
>> hosts, for example the same single NIC can be shared for multiple
>> server units in the rack. On each PCIe link NIC can provide multiple
>> PFs and VFs/SFs based on these ones. The full representor identifier
>> consists of three indices - controller index, PF index, and VF or SF index (if any).
>>
>> SR-IOV and SubFunction are created on top of PF. PF index is
>> introduced because there might be multiple PFs in the bonding
>> configuration and only bonding device is probed.
>>
>> In eth representor comparator callback, ethdev representor ID was
>> compared with devarg. Since controller index and PF index not
>> compared, callback returned representor from other PF or controller.
>>
>> This patch adds new API to get representor ID from controller, pf and
>> vf/sf index. Representor comparer callback get representor ID then
>> compare with device representor ID.
>>
>> Signed-off-by: Xueming Li <xuemingl at nvidia.com>
>
>Reviewed-by: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
>
>One minor suggestions below to make it a bit more robust against errors in PMDs.
>
>Make thanks for careful review notes processing.

Many thanks to your generous and careful review all the time, with patience :)
This is my first long public api patchset, can't do it without your help :)

>
>[snip]
>
>> diff --git a/lib/librte_ethdev/rte_ethdev.c
>> b/lib/librte_ethdev/rte_ethdev.c index 3d4ec8ad5c..2dc464a7ad 100644
>> --- a/lib/librte_ethdev/rte_ethdev.c
>> +++ b/lib/librte_ethdev/rte_ethdev.c
>> @@ -5609,6 +5609,94 @@ rte_eth_devargs_parse(const char *dargs, struct rte_eth_devargs *eth_da)
>>  	return result;
>>  }
>>
>> +int
>> +rte_eth_representor_id_get(const struct rte_eth_dev *ethdev,
>> +			   enum rte_eth_representor_type type,
>> +			   int controller, int pf, int representor_port,
>> +			   uint16_t *repr_id)
>> +{
>> +	int ret, n, i, count;
>> +	struct rte_eth_representor_info *info = NULL;
>> +	size_t size;
>> +
>> +	if (type == RTE_ETH_REPRESENTOR_NONE)
>> +		return 0;
>> +	if (repr_id == NULL)
>> +		return -EINVAL;
>> +
>> +	/* Get PMD representor range info. */
>> +	ret = rte_eth_representor_info_get(ethdev->data->port_id, NULL);
>> +	if (ret < 0) {
>> +		if (type == RTE_ETH_REPRESENTOR_VF && controller == -1 &&
>> +		    pf == -1) {
>> +			/* Direct mapping for legacy VF representor. */
>> +			*repr_id = representor_port;
>> +			return 0;
>> +		} else {
>> +			return ret;
>> +		}
>> +	}
>> +	n = ret;
>> +	size = sizeof(*info) + n * sizeof(info->ranges[0]);
>> +	info = calloc(1, size);
>> +	if (info == NULL)
>> +		return -ENOMEM;
>> +	ret = rte_eth_representor_info_get(ethdev->data->port_id, info);
>> +	if (ret < 0)
>> +		goto out;
>> +
>> +	/* Default controller and pf to caller. */
>> +	if (controller == -1)
>> +		controller = info->controller;
>> +	if (pf == -1)
>> +		pf = info->pf;
>> +
>> +	/* Locate representor ID. */
>> +	ret = -ENOENT;
>> +	for (i = 0; i < n; ++i) {
>> +		if (info->ranges[i].type != type)
>> +			continue;
>> +		if (info->ranges[i].controller != controller)
>> +			continue;
>> +		count = info->ranges[i].id_end - info->ranges[i].id_base + 1;
>
>I think it would be useful to sanity test these values to ensure that we have no overflow here.
>Let's check above, log error and skip the range if id_end is smaller than id_base.
>
>> +		switch (info->ranges[i].type) {
>> +		case RTE_ETH_REPRESENTOR_PF:
>> +			if (pf < info->ranges[i].pf ||
>> +			    pf >= info->ranges[i].pf + count)
>> +				continue;
>> +			*repr_id = info->ranges[i].id_base +
>> +				   (pf - info->ranges[i].pf);
>> +			ret = 0;
>> +			goto out;
>> +		case RTE_ETH_REPRESENTOR_VF:
>> +			if (info->ranges[i].pf != pf)
>> +				continue;
>> +			if (representor_port < info->ranges[i].vf ||
>> +			    representor_port >= info->ranges[i].vf + count)
>> +				continue;
>> +			*repr_id = info->ranges[i].id_base +
>> +				   (representor_port - info->ranges[i].vf);
>> +			ret = 0;
>> +			goto out;
>> +		case RTE_ETH_REPRESENTOR_SF:
>> +			if (info->ranges[i].pf != pf)
>> +				continue;
>> +			if (representor_port < info->ranges[i].sf ||
>> +			    representor_port >= info->ranges[i].sf + count)
>> +				continue;
>> +			*repr_id = info->ranges[i].id_base +
>> +			      (representor_port - info->ranges[i].sf);
>> +			ret = 0;
>> +			goto out;
>> +		default:
>> +			break;
>> +		}
>> +	}
>> +out:
>> +	free(info);
>> +	return ret;
>> +}
>> +
>>  static int
>>  eth_dev_handle_port_list(const char *cmd __rte_unused,
>>  		const char *params __rte_unused,
>
>[snip]