On Sat, Dec 12, 2020 at 2:59 PM Jakub Kicinski [off-list ref] wrote:

On Tue,  8 Dec 2020 16:54:44 -0800 Wei Wang wrote:

quoted

+static void dev_disable_threaded_all(struct net_device *dev)
+{
+     struct napi_struct *napi;
+
+     list_for_each_entry(napi, &dev->napi_list, dev_list)
+             napi_set_threaded(napi, false);
+}

This is an implementation detail which should be hidden in dev.c IMHO.
Since the sysfs knob is just a device global on/off the iteration over
napis and all is best hidden away.

OK. Will move it.

(sorry about the delayed review BTW, hope we can do a minor revision
and still hit 5.12)

quoted

+static int modify_napi_threaded(struct net_device *dev, unsigned long val)
+{
+     struct napi_struct *napi;
+     int ret;
+
+     if (list_empty(&dev->napi_list))
+             return -EOPNOTSUPP;
+
+     list_for_each_entry(napi, &dev->napi_list, dev_list) {
+             ret = napi_set_threaded(napi, !!val);
+             if (ret) {
+                     /* Error occurred on one of the napi,
+                      * reset threaded mode on all napi.
+                      */
+                     dev_disable_threaded_all(dev);
+                     break;
+             }
+     }
+
+     return ret;
+}