docs: networking: document NAPI

Add basic documentation about NAPI. We can stop linking to the ancient
doc on the LF wiki.

Link: https://lore.kernel.org/all/[email protected]/
Reviewed-by: Bagas Sanjaya <[email protected]>
Reviewed-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Pavel Pisa <[email protected]> # for ctucanfd-driver.rst
Reviewed-by: Tony Nguyen <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Reviewed-by: Stephen Hemminger <[email protected]>
Reviewed-by: Randy Dunlap <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

1 files changed, 8 insertions, 5 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 674ee5daa7b1..18a5be6ddd0f 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -509,15 +509,18 @@ static inline bool napi_reschedule(struct napi_struct *napi)
 	return false;
 }
 
-bool napi_complete_done(struct napi_struct *n, int work_done);
 /**
- *	napi_complete - NAPI processing complete
- *	@n: NAPI context
+ * napi_complete_done - NAPI processing complete
+ * @n: NAPI context
+ * @work_done: number of packets processed
  *
- * Mark NAPI processing as complete.
- * Consider using napi_complete_done() instead.
+ * Mark NAPI processing as complete. Should only be called if poll budget
+ * has not been completely consumed.
+ * Prefer over napi_complete().
  * Return false if device should avoid rearming interrupts.
  */
+bool napi_complete_done(struct napi_struct *n, int work_done);
+
 static inline bool napi_complete(struct napi_struct *n)
 {
 	return napi_complete_done(n, 0);