Commit 977f1aa5 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: bql: add more documentation 



Add some documentation for netdev_tx_sent_queue() and
netdev_tx_completed_queue()

Stating that netdev_tx_completed_queue() must be called once
per TX completion round is apparently not obvious for everybody.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 25de4a0b

include/linux/netdevice.h

+26 −6
Original line number Diff line number Diff line
@@ -3353,6 +3353,16 @@ static inline void netdev_txq_bql_complete_prefetchw(struct netdev_queue *dev_qu 
#endif

}



/**

 *	netdev_tx_sent_queue - report the number of bytes queued to a given tx queue

 *	@dev_queue: network device queue

 *	@bytes: number of bytes queued to the device queue

 *

 *	Report the number of bytes queued for sending/completion to the network

 *	device hardware queue. @bytes should be a good approximation and should

 *	exactly match netdev_completed_queue() @bytes.

 *	This is typically called once per packet, from ndo_start_xmit().

 */

static inline void netdev_tx_sent_queue(struct netdev_queue *dev_queue,

					unsigned int bytes)

{
@@ -3403,8 +3413,9 @@ static inline bool __netdev_tx_sent_queue(struct netdev_queue *dev_queue, 
 *	@bytes: number of bytes queued to the hardware device queue

 *

 *	Report the number of bytes queued for sending/completion to the network

 * 	device hardware queue. @bytes should be a good approximation and should

 * 	exactly match netdev_completed_queue() @bytes

 *	device hardware queue#0. @bytes should be a good approximation and should

 *	exactly match netdev_completed_queue() @bytes.

 *	This is typically called once per packet, from ndo_start_xmit().

 */

static inline void netdev_sent_queue(struct net_device *dev, unsigned int bytes)

{
@@ -3419,6 +3430,15 @@ static inline bool __netdev_sent_queue(struct net_device *dev, 
				      xmit_more);

}



/**

 *	netdev_tx_completed_queue - report number of packets/bytes at TX completion.

 *	@dev_queue: network device queue

 *	@pkts: number of packets (currently ignored)

 *	@bytes: number of bytes dequeued from the device queue

 *

 *	Must be called at most once per TX completion round (and not per

 *	individual packet), so that BQL can adjust its limits appropriately.

 */

static inline void netdev_tx_completed_queue(struct netdev_queue *dev_queue,

					     unsigned int pkts, unsigned int bytes)

{