Commit d4fb6514 authored by Oliver Hartkopp's avatar Oliver Hartkopp Committed by Paolo Abeni
Browse files

can: use skb hash instead of private variable in headroom 



The can_skb_priv::skbcnt variable is used to identify CAN skbs in the RX
path analogue to the skb->hash.

As the skb hash is not filled in CAN skbs move the private skbcnt value to
skb->hash and set skb->sw_hash accordingly. The skb->hash is a value used
for RPS to identify skbs. Use it as intended.

Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-1-3635d790fe8b@hartkopp.net


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 0cbcc0fd

drivers/net/can/dev/skb.c

+0 −2
Original line number Diff line number Diff line
@@ -202,7 +202,6 @@ static void init_can_skb_reserve(struct sk_buff *skb) 
	skb_reset_transport_header(skb);



	can_skb_reserve(skb);

	can_skb_prv(skb)->skbcnt = 0;

}



struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
@@ -312,7 +311,6 @@ static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb) 
	if (skb->ip_summed == CHECKSUM_NONE) {

		/* init headroom */

		can_skb_prv(skb)->ifindex = dev->ifindex;

		can_skb_prv(skb)->skbcnt = 0;



		skb->ip_summed = CHECKSUM_UNNECESSARY;

include/linux/can/core.h

+1 −0
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ extern void can_rx_unregister(struct net *net, struct net_device *dev, 
			      void *data);



extern int can_send(struct sk_buff *skb, int loop);

void can_set_skb_uid(struct sk_buff *skb);

void can_sock_destruct(struct sock *sk);



#endif /* !_CAN_CORE_H */

include/linux/can/skb.h

+0 −2
Original line number Diff line number Diff line
@@ -49,13 +49,11 @@ bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb); 
/**

 * struct can_skb_priv - private additional data inside CAN sk_buffs

 * @ifindex:	ifindex of the first interface the CAN frame appeared on

 * @skbcnt:	atomic counter to have an unique id together with skb pointer

 * @frame_len:	length of CAN frame in data link layer

 * @cf:		align to the following CAN frame at skb->data

 */

struct can_skb_priv {

	int ifindex;

	int skbcnt;

	unsigned int frame_len;

	struct can_frame cf[];

};

net/can/af_can.c

+11 −3
Original line number Diff line number Diff line
@@ -641,6 +641,16 @@ static int can_rcv_filter(struct can_dev_rcv_lists *dev_rcv_lists, struct sk_buf 
	return matches;

}



void can_set_skb_uid(struct sk_buff *skb)

{

	/* create non-zero unique skb identifier together with *skb */

	while (!(skb->hash))

		skb->hash = atomic_inc_return(&skbcounter);



	skb->sw_hash = 1;

}

EXPORT_SYMBOL(can_set_skb_uid);



static void can_receive(struct sk_buff *skb, struct net_device *dev)

{

	struct can_dev_rcv_lists *dev_rcv_lists;
@@ -652,9 +662,7 @@ static void can_receive(struct sk_buff *skb, struct net_device *dev) 
	atomic_long_inc(&pkg_stats->rx_frames);

	atomic_long_inc(&pkg_stats->rx_frames_delta);



	/* create non-zero unique skb identifier together with *skb */

	while (!(can_skb_prv(skb)->skbcnt))

		can_skb_prv(skb)->skbcnt = atomic_inc_return(&skbcounter);

	can_set_skb_uid(skb);



	rcu_read_lock();

net/can/bcm.c

+0 −2
Original line number Diff line number Diff line
@@ -316,7 +316,6 @@ static void bcm_can_tx(struct bcm_op *op) 


	can_skb_reserve(skb);

	can_skb_prv(skb)->ifindex = dev->ifindex;

	can_skb_prv(skb)->skbcnt = 0;



	skb_put_data(skb, cf, op->cfsiz);
@@ -1344,7 +1343,6 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk, 
	}



	can_skb_prv(skb)->ifindex = dev->ifindex;

	can_skb_prv(skb)->skbcnt = 0;

	skb->dev = dev;

	can_skb_set_owner(skb, sk);

	err = can_send(skb, 1); /* send with loopback */