Re: [PATCH net-next 06/19] net/mlx5: Add support for mediated devices in switchdev mode

[Jiri Pirko <jiri@resnulli.us>]

Fri, Nov 08, 2019 at 05:03:13PM CET, parav@mellanox.com wrote:
>
>
>> -----Original Message-----
>> From: Jiri Pirko <jiri@resnulli.us>
>> Sent: Friday, November 8, 2019 4:33 AM
>> To: Parav Pandit <parav@mellanox.com>
>> Cc: alex.williamson@redhat.com; davem@davemloft.net;
>> kvm@vger.kernel.org; netdev@vger.kernel.org; Saeed Mahameed
>> <saeedm@mellanox.com>; kwankhede@nvidia.com; leon@kernel.org;
>> cohuck@redhat.com; Jiri Pirko <jiri@mellanox.com>; linux-
>> rdma@vger.kernel.org; Vu Pham <vuhuong@mellanox.com>
>> Subject: Re: [PATCH net-next 06/19] net/mlx5: Add support for mediated
>> devices in switchdev mode
>> 
>> Thu, Nov 07, 2019 at 05:08:21PM CET, parav@mellanox.com wrote:
>> >From: Vu Pham <vuhuong@mellanox.com>
>> 
>> [...]
>> 
>> 
>> >+static ssize_t
>> >+max_mdevs_show(struct kobject *kobj, struct device *dev, char *buf) {
>> >+	struct pci_dev *pdev = to_pci_dev(dev);
>> >+	struct mlx5_core_dev *coredev;
>> >+	struct mlx5_mdev_table *table;
>> >+	u16 max_sfs;
>> >+
>> >+	coredev = pci_get_drvdata(pdev);
>> >+	table = coredev->priv.eswitch->mdev_table;
>> >+	max_sfs = mlx5_core_max_sfs(coredev, &table->sf_table);
>> >+
>> >+	return sprintf(buf, "%d\n", max_sfs); } static
>> >+MDEV_TYPE_ATTR_RO(max_mdevs);
>> >+
>> >+static ssize_t
>> >+available_instances_show(struct kobject *kobj, struct device *dev,
>> >+char *buf) {
>> >+	struct pci_dev *pdev = to_pci_dev(dev);
>> >+	struct mlx5_core_dev *coredev;
>> >+	struct mlx5_mdev_table *table;
>> >+	u16 free_sfs;
>> >+
>> >+	coredev = pci_get_drvdata(pdev);
>> >+	table = coredev->priv.eswitch->mdev_table;
>> >+	free_sfs = mlx5_get_free_sfs(coredev, &table->sf_table);
>> >+	return sprintf(buf, "%d\n", free_sfs); } static
>> >+MDEV_TYPE_ATTR_RO(available_instances);
>> 
>> These 2 arbitrary sysfs files are showing resource size/usage for the whole
>> eswitch/asic. That is a job for "devlink resource". Please implement that.
>>
>Jiri,
>This series is already too long. I will implement it as follow on. It is already in plan.
>However, available_instances file is needed regardless of devlink resource, as its read by the userspace for all mdev drivers.

If that is the case, why isn't that implemented in mdev code rather than
individual drivers? I don't understand.


> 
>> 
>> >+
>> >+static struct attribute *mdev_dev_attrs[] = {
>> >+	&mdev_type_attr_max_mdevs.attr,
>> >+	&mdev_type_attr_available_instances.attr,
>> >+	NULL,
>> >+};
>> >+
>> >+static struct attribute_group mdev_mgmt_group = {
>> >+	.name  = "local",
>> >+	.attrs = mdev_dev_attrs,
>> >+};
>> >+
>> >+static struct attribute_group *mlx5_meddev_groups[] = {
>> >+	&mdev_mgmt_group,
>> >+	NULL,
>> >+};
>> 
>> [...]