Tue, May 12, 2020 at 05:07:14PM CEST, [email protected] wrote:
>On Tue, May 12, 2020 at 05:03:06PM +0200, Jiri Pirko wrote:
>> Tue, May 12, 2020 at 04:53:52PM CEST, [email protected] wrote:
>> >On Mon, May 11, 2020 at 12:32:22PM +0200, Jiri Pirko wrote:
>> >
>> >[...]
>> >
>> >>
>> >> This is RCU list. Treat it accordingly.
>> >>
>> >>
>> >> >+ spin_unlock(&sw->ports_lock);
>> >>
>> >> I don't follow, why do you need to protect the list by spinlock here?
>> >> More to that, why do you need the port_list reader-writer
>> >> protected (by rcu)? Is is possible that you add/remove port in the same
>> >> time packets are flying in?
>> >>
>> >> If yes, you need to ensure the structs are in the memory (free_rcu,
>> >> synchronize_rcu). But I believe that you should disable that from
>> >> happening in HW.
>> >>
>> >>
>> >> >+
>> >
>> >[...]
>> >
>> >> >+
>> >> >+static int prestera_switch_init(struct prestera_switch *sw)
>> >> >+{
>> >> >+ int err;
>> >> >+
>> >> >+ err = prestera_hw_switch_init(sw);
>> >> >+ if (err) {
>> >> >+ dev_err(prestera_dev(sw), "Failed to init Switch
>> >> >device\n");
>> >> >+ return err;
>> >> >+ }
>> >> >+
>> >> >+ memcpy(sw->base_mac, base_mac_addr, sizeof(sw->base_mac));
>> >> >+ spin_lock_init(&sw->ports_lock);
>> >> >+ INIT_LIST_HEAD(&sw->port_list);
>> >> >+
>> >> >+ err = prestera_hw_switch_mac_set(sw, sw->base_mac);
>> >> >+ if (err)
>> >> >+ return err;
>> >> >+
>> >> >+ err = prestera_rxtx_switch_init(sw);
>> >> >+ if (err)
>> >> >+ return err;
>> >> >+
>> >> >+ err = prestera_event_handlers_register(sw);
>> >> >+ if (err)
>> >> >+ goto err_evt_handlers;
>> >> >+
>> >> >+ err = prestera_create_ports(sw);
>> >> >+ if (err)
>> >> >+ goto err_ports_create;
>> >> >+
>> >> >+ return 0;
>> >> >+
>> >> >+err_ports_create:
>> >>
>> >> You are missing prestera_event_handlers_unregister(sw); call here.
>> >>
>> >it is handled below in prestera_switch_fini().
>>
>> Sure, but you should call it here in the error path as well. That is my
>> point.
>>
>I understand your point - to make error path more clear, and symmetric ?
Yes.
>
>> >
>> >>
>> >> >+err_evt_handlers:
>> >> >+ prestera_rxtx_switch_fini(sw);
>> >> >+
>> >> >+ return err;
>> >> >+}
>> >> >+
>> >> >+static void prestera_switch_fini(struct prestera_switch *sw)
>> >> >+{
>> >> >+ prestera_destroy_ports(sw);
>> >> >+ prestera_event_handlers_unregister(sw);
>> >> >+ prestera_rxtx_switch_fini(sw);
>> >> >+}
>> >> >+
>> >> >+int prestera_device_register(struct prestera_device *dev)
>> >> >+{
>> >> >+ struct prestera_switch *sw;
>> >> >+ int err;
>> >> >+
>> >> >+ sw = kzalloc(sizeof(*sw), GFP_KERNEL);
>> >> >+ if (!sw)
>> >> >+ return -ENOMEM;
>> >> >+
>> >> >+ dev->priv = sw;
>> >> >+ sw->dev = dev;
>> >> >+
>> >> >+ err = prestera_switch_init(sw);
>> >> >+ if (err) {
>> >> >+ kfree(sw);
>> >> >+ return err;
>> >> >+ }
>> >> >+
>> >> >+ registered_switch = sw;
>> >> >+ return 0;
>> >> >+}
>> >> >+EXPORT_SYMBOL(prestera_device_register);
>> >> >+
>> >> >+void prestera_device_unregister(struct prestera_device *dev)
>> >> >+{
>> >> >+ struct prestera_switch *sw = dev->priv;
>> >> >+
>> >> >+ registered_switch = NULL;
>> >> >+ prestera_switch_fini(sw);
>> >> >+ kfree(sw);
>> >> >+}
>> >> >+EXPORT_SYMBOL(prestera_device_unregister);
>> >> >+
>> >> >+static int __init prestera_module_init(void)
>> >> >+{
>> >> >+ if (!base_mac) {
>> >> >+ pr_err("[base_mac] parameter must be specified\n");
>> >> >+ return -EINVAL;
>> >> >+ }
>> >> >+ if (!mac_pton(base_mac, base_mac_addr)) {
>> >> >+ pr_err("[base_mac] parameter has invalid format\n");
>> >> >+ return -EINVAL;
>> >> >+ }
>> >> >+
>> >> >+ prestera_wq = alloc_workqueue("prestera", 0, 0);
>> >> >+ if (!prestera_wq)
>> >> >+ return -ENOMEM;
>> >> >+
>> >> >+ return 0;
>> >> >+}
>> >> >+
>> >> >+static void __exit prestera_module_exit(void)
>> >> >+{
>> >> >+ destroy_workqueue(prestera_wq);
>> >> >+}
>> >> >+
>> >> >+module_init(prestera_module_init);
>> >> >+module_exit(prestera_module_exit);
>> >> >+
>> >> >+MODULE_AUTHOR("Marvell Semi.");
>> >> >+MODULE_LICENSE("Dual BSD/GPL");
>> >> >+MODULE_DESCRIPTION("Marvell Prestera switch driver");
>> >> >+
>> >> >+module_param(base_mac, charp, 0);
>> >>
>> >> No please.
>> >>
>> >>
>> >> [..]
>> >>
