diff options
| -rw-r--r-- | net/can/af_can.c | 31 | ||||
| -rw-r--r-- | net/can/af_can.h | 5 | ||||
| -rw-r--r-- | net/can/proc.c | 48 |
3 files changed, 75 insertions, 9 deletions
diff --git a/net/can/af_can.c b/net/can/af_can.c index a27f8aad9e99..ce82337521f6 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -338,6 +338,29 @@ static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev) } /** + * effhash - hash function for 29 bit CAN identifier reduction + * @can_id: 29 bit CAN identifier + * + * Description: + * To reduce the linear traversal in one linked list of _single_ EFF CAN + * frame subscriptions the 29 bit identifier is mapped to 10 bits. + * (see CAN_EFF_RCV_HASH_BITS definition) + * + * Return: + * Hash value from 0x000 - 0x3FF ( enforced by CAN_EFF_RCV_HASH_BITS mask ) + */ +static unsigned int effhash(canid_t can_id) +{ + unsigned int hash; + + hash = can_id; + hash ^= can_id >> CAN_EFF_RCV_HASH_BITS; + hash ^= can_id >> (2 * CAN_EFF_RCV_HASH_BITS); + + return hash & ((1 << CAN_EFF_RCV_HASH_BITS) - 1); +} + +/** * find_rcv_list - determine optimal filterlist inside device filter struct * @can_id: pointer to CAN identifier of a given can_filter * @mask: pointer to CAN mask of a given can_filter @@ -400,10 +423,8 @@ static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask, !(*can_id & CAN_RTR_FLAG)) { if (*can_id & CAN_EFF_FLAG) { - if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS)) { - /* RFC: a future use-case for hash-tables? */ - return &d->rx[RX_EFF]; - } + if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS)) + return &d->rx_eff[effhash(*can_id)]; } else { if (*mask == (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS)) return &d->rx_sff[*can_id]; @@ -632,7 +653,7 @@ static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb) return matches; if (can_id & CAN_EFF_FLAG) { - hlist_for_each_entry_rcu(r, &d->rx[RX_EFF], list) { + hlist_for_each_entry_rcu(r, &d->rx_eff[effhash(can_id)], list) { if (r->can_id == can_id) { deliver(skb, r); matches++; diff --git a/net/can/af_can.h b/net/can/af_can.h index b4bdaa32d7a4..fca0fe9fc45a 100644 --- a/net/can/af_can.h +++ b/net/can/af_can.h @@ -60,13 +60,16 @@ struct receiver { }; #define CAN_SFF_RCV_ARRAY_SZ (1 << CAN_SFF_ID_BITS) +#define CAN_EFF_RCV_HASH_BITS 10 +#define CAN_EFF_RCV_ARRAY_SZ (1 << CAN_EFF_RCV_HASH_BITS) -enum { RX_ERR, RX_ALL, RX_FIL, RX_INV, RX_EFF, RX_MAX }; +enum { RX_ERR, RX_ALL, RX_FIL, RX_INV, RX_MAX }; /* per device receive filters linked at dev->ml_priv */ struct dev_rcv_lists { struct hlist_head rx[RX_MAX]; struct hlist_head rx_sff[CAN_SFF_RCV_ARRAY_SZ]; + struct hlist_head rx_eff[CAN_EFF_RCV_ARRAY_SZ]; int remove_on_zero_entries; int entries; }; diff --git a/net/can/proc.c b/net/can/proc.c index 1621e5909ee6..1a19b985a868 100644 --- a/net/can/proc.c +++ b/net/can/proc.c @@ -80,7 +80,6 @@ static const char rx_list_name[][8] = { [RX_ALL] = "rx_all", [RX_FIL] = "rx_fil", [RX_INV] = "rx_inv", - [RX_EFF] = "rx_eff", }; /* @@ -456,6 +455,49 @@ static const struct file_operations can_rcvlist_sff_proc_fops = { .release = single_release, }; + +static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v) +{ + struct net_device *dev; + struct dev_rcv_lists *d; + + /* RX_EFF */ + seq_puts(m, "\nreceive list 'rx_eff':\n"); + + rcu_read_lock(); + + /* eff receive list for 'all' CAN devices (dev == NULL) */ + d = &can_rx_alldev_list; + can_rcvlist_proc_show_array(m, NULL, d->rx_eff, ARRAY_SIZE(d->rx_eff)); + + /* eff receive list for registered CAN devices */ + for_each_netdev_rcu(&init_net, dev) { + if (dev->type == ARPHRD_CAN && dev->ml_priv) { + d = dev->ml_priv; + can_rcvlist_proc_show_array(m, dev, d->rx_eff, + ARRAY_SIZE(d->rx_eff)); + } + } + + rcu_read_unlock(); + + seq_putc(m, '\n'); + return 0; +} + +static int can_rcvlist_eff_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, can_rcvlist_eff_proc_show, NULL); +} + +static const struct file_operations can_rcvlist_eff_proc_fops = { + .owner = THIS_MODULE, + .open = can_rcvlist_eff_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + /* * proc utility functions */ @@ -495,8 +537,8 @@ void can_init_proc(void) &can_rcvlist_proc_fops, (void *)RX_FIL); pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir, &can_rcvlist_proc_fops, (void *)RX_INV); - pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir, - &can_rcvlist_proc_fops, (void *)RX_EFF); + pde_rcvlist_eff = proc_create(CAN_PROC_RCVLIST_EFF, 0644, can_dir, + &can_rcvlist_eff_proc_fops); pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir, &can_rcvlist_sff_proc_fops); } |