aboutsummaryrefslogtreecommitdiff
path: root/net/can/bcm.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/can/bcm.c')
-rw-r--r--net/can/bcm.c208
1 files changed, 125 insertions, 83 deletions
diff --git a/net/can/bcm.c b/net/can/bcm.c
index da0d426c0ce..6248ae2502c 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -70,7 +70,7 @@
#define CAN_BCM_VERSION CAN_VERSION
static __initdata const char banner[] = KERN_INFO
- "can: broadcast manager protocol (rev " CAN_BCM_VERSION ")\n";
+ "can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n";
MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
MODULE_LICENSE("Dual BSD/GPL");
@@ -90,6 +90,7 @@ struct bcm_op {
unsigned long frames_abs, frames_filtered;
struct timeval ival1, ival2;
struct hrtimer timer, thrtimer;
+ struct tasklet_struct tsklet, thrtsklet;
ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg;
int rx_ifindex;
int count;
@@ -341,6 +342,23 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
}
}
+static void bcm_tx_timeout_tsklet(unsigned long data)
+{
+ struct bcm_op *op = (struct bcm_op *)data;
+ struct bcm_msg_head msg_head;
+
+ /* create notification to user */
+ msg_head.opcode = TX_EXPIRED;
+ msg_head.flags = op->flags;
+ msg_head.count = op->count;
+ msg_head.ival1 = op->ival1;
+ msg_head.ival2 = op->ival2;
+ msg_head.can_id = op->can_id;
+ msg_head.nframes = 0;
+
+ bcm_send_to_user(op, &msg_head, NULL, 0);
+}
+
/*
* bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
*/
@@ -352,20 +370,8 @@ static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
if (op->kt_ival1.tv64 && (op->count > 0)) {
op->count--;
- if (!op->count && (op->flags & TX_COUNTEVT)) {
- struct bcm_msg_head msg_head;
-
- /* create notification to user */
- msg_head.opcode = TX_EXPIRED;
- msg_head.flags = op->flags;
- msg_head.count = op->count;
- msg_head.ival1 = op->ival1;
- msg_head.ival2 = op->ival2;
- msg_head.can_id = op->can_id;
- msg_head.nframes = 0;
-
- bcm_send_to_user(op, &msg_head, NULL, 0);
- }
+ if (!op->count && (op->flags & TX_COUNTEVT))
+ tasklet_schedule(&op->tsklet);
}
if (op->kt_ival1.tv64 && (op->count > 0)) {
@@ -402,6 +408,9 @@ static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
if (op->frames_filtered > ULONG_MAX/100)
op->frames_filtered = op->frames_abs = 0;
+ /* this element is not throttled anymore */
+ data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV);
+
head.opcode = RX_CHANGED;
head.flags = op->flags;
head.count = op->count;
@@ -420,37 +429,32 @@ static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
*/
static void bcm_rx_update_and_send(struct bcm_op *op,
struct can_frame *lastdata,
- struct can_frame *rxdata)
+ const struct can_frame *rxdata)
{
memcpy(lastdata, rxdata, CFSIZ);
- /* mark as used */
- lastdata->can_dlc |= RX_RECV;
+ /* mark as used and throttled by default */
+ lastdata->can_dlc |= (RX_RECV|RX_THR);
- /* throtteling mode inactive OR data update already on the run ? */
- if (!op->kt_ival2.tv64 || hrtimer_callback_running(&op->thrtimer)) {
+ /* throtteling mode inactive ? */
+ if (!op->kt_ival2.tv64) {
/* send RX_CHANGED to the user immediately */
- bcm_rx_changed(op, rxdata);
+ bcm_rx_changed(op, lastdata);
return;
}
- if (hrtimer_active(&op->thrtimer)) {
- /* mark as 'throttled' */
- lastdata->can_dlc |= RX_THR;
+ /* with active throttling timer we are just done here */
+ if (hrtimer_active(&op->thrtimer))
return;
- }
- if (!op->kt_lastmsg.tv64) {
- /* send first RX_CHANGED to the user immediately */
- bcm_rx_changed(op, rxdata);
- op->kt_lastmsg = ktime_get();
- return;
- }
+ /* first receiption with enabled throttling mode */
+ if (!op->kt_lastmsg.tv64)
+ goto rx_changed_settime;
+ /* got a second frame inside a potential throttle period? */
if (ktime_us_delta(ktime_get(), op->kt_lastmsg) <
ktime_to_us(op->kt_ival2)) {
- /* mark as 'throttled' and start timer */
- lastdata->can_dlc |= RX_THR;
+ /* do not send the saved data - only start throttle timer */
hrtimer_start(&op->thrtimer,
ktime_add(op->kt_lastmsg, op->kt_ival2),
HRTIMER_MODE_ABS);
@@ -458,7 +462,8 @@ static void bcm_rx_update_and_send(struct bcm_op *op,
}
/* the gap was that big, that throttling was not needed here */
- bcm_rx_changed(op, rxdata);
+rx_changed_settime:
+ bcm_rx_changed(op, lastdata);
op->kt_lastmsg = ktime_get();
}
@@ -467,7 +472,7 @@ static void bcm_rx_update_and_send(struct bcm_op *op,
* received data stored in op->last_frames[]
*/
static void bcm_rx_cmp_to_index(struct bcm_op *op, int index,
- struct can_frame *rxdata)
+ const struct can_frame *rxdata)
{
/*
* no one uses the MSBs of can_dlc for comparation,
@@ -511,14 +516,12 @@ static void bcm_rx_starttimer(struct bcm_op *op)
hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
}
-/*
- * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
- */
-static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
+static void bcm_rx_timeout_tsklet(unsigned long data)
{
- struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
+ struct bcm_op *op = (struct bcm_op *)data;
struct bcm_msg_head msg_head;
+ /* create notification to user */
msg_head.opcode = RX_TIMEOUT;
msg_head.flags = op->flags;
msg_head.count = op->count;
@@ -528,6 +531,17 @@ static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
msg_head.nframes = 0;
bcm_send_to_user(op, &msg_head, NULL, 0);
+}
+
+/*
+ * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
+ */
+static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
+{
+ struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
+
+ /* schedule before NET_RX_SOFTIRQ */
+ tasklet_hi_schedule(&op->tsklet);
/* no restart of the timer is done here! */
@@ -541,9 +555,25 @@ static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
}
/*
+ * bcm_rx_do_flush - helper for bcm_rx_thr_flush
+ */
+static inline int bcm_rx_do_flush(struct bcm_op *op, int update, int index)
+{
+ if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) {
+ if (update)
+ bcm_rx_changed(op, &op->last_frames[index]);
+ return 1;
+ }
+ return 0;
+}
+
+/*
* bcm_rx_thr_flush - Check for throttled data and send it to the userspace
+ *
+ * update == 0 : just check if throttled data is available (any irq context)
+ * update == 1 : check and send throttled data to userspace (soft_irq context)
*/
-static int bcm_rx_thr_flush(struct bcm_op *op)
+static int bcm_rx_thr_flush(struct bcm_op *op, int update)
{
int updated = 0;
@@ -551,27 +581,25 @@ static int bcm_rx_thr_flush(struct bcm_op *op)
int i;
/* for MUX filter we start at index 1 */
- for (i = 1; i < op->nframes; i++) {
- if ((op->last_frames) &&
- (op->last_frames[i].can_dlc & RX_THR)) {
- op->last_frames[i].can_dlc &= ~RX_THR;
- bcm_rx_changed(op, &op->last_frames[i]);
- updated++;
- }
- }
+ for (i = 1; i < op->nframes; i++)
+ updated += bcm_rx_do_flush(op, update, i);
} else {
/* for RX_FILTER_ID and simple filter */
- if (op->last_frames && (op->last_frames[0].can_dlc & RX_THR)) {
- op->last_frames[0].can_dlc &= ~RX_THR;
- bcm_rx_changed(op, &op->last_frames[0]);
- updated++;
- }
+ updated += bcm_rx_do_flush(op, update, 0);
}
return updated;
}
+static void bcm_rx_thr_tsklet(unsigned long data)
+{
+ struct bcm_op *op = (struct bcm_op *)data;
+
+ /* push the changed data to the userspace */
+ bcm_rx_thr_flush(op, 1);
+}
+
/*
* bcm_rx_thr_handler - the time for blocked content updates is over now:
* Check for throttled data and send it to the userspace
@@ -580,7 +608,9 @@ static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer)
{
struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer);
- if (bcm_rx_thr_flush(op)) {
+ tasklet_schedule(&op->thrtsklet);
+
+ if (bcm_rx_thr_flush(op, 0)) {
hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
return HRTIMER_RESTART;
} else {
@@ -596,48 +626,38 @@ static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer)
static void bcm_rx_handler(struct sk_buff *skb, void *data)
{
struct bcm_op *op = (struct bcm_op *)data;
- struct can_frame rxframe;
+ const struct can_frame *rxframe = (struct can_frame *)skb->data;
int i;
/* disable timeout */
hrtimer_cancel(&op->timer);
- if (skb->len == sizeof(rxframe)) {
- memcpy(&rxframe, skb->data, sizeof(rxframe));
- /* save rx timestamp */
- op->rx_stamp = skb->tstamp;
- /* save originator for recvfrom() */
- op->rx_ifindex = skb->dev->ifindex;
- /* update statistics */
- op->frames_abs++;
- kfree_skb(skb);
+ if (op->can_id != rxframe->can_id)
+ goto rx_freeskb;
- } else {
- kfree_skb(skb);
- return;
- }
-
- if (op->can_id != rxframe.can_id)
- return;
+ /* save rx timestamp */
+ op->rx_stamp = skb->tstamp;
+ /* save originator for recvfrom() */
+ op->rx_ifindex = skb->dev->ifindex;
+ /* update statistics */
+ op->frames_abs++;
if (op->flags & RX_RTR_FRAME) {
/* send reply for RTR-request (placed in op->frames[0]) */
bcm_can_tx(op);
- return;
+ goto rx_freeskb;
}
if (op->flags & RX_FILTER_ID) {
/* the easiest case */
- bcm_rx_update_and_send(op, &op->last_frames[0], &rxframe);
- bcm_rx_starttimer(op);
- return;
+ bcm_rx_update_and_send(op, &op->last_frames[0], rxframe);
+ goto rx_freeskb_starttimer;
}
if (op->nframes == 1) {
/* simple compare with index 0 */
- bcm_rx_cmp_to_index(op, 0, &rxframe);
- bcm_rx_starttimer(op);
- return;
+ bcm_rx_cmp_to_index(op, 0, rxframe);
+ goto rx_freeskb_starttimer;
}
if (op->nframes > 1) {
@@ -649,15 +669,19 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data)
*/
for (i = 1; i < op->nframes; i++) {
- if ((GET_U64(&op->frames[0]) & GET_U64(&rxframe)) ==
+ if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) ==
(GET_U64(&op->frames[0]) &
GET_U64(&op->frames[i]))) {
- bcm_rx_cmp_to_index(op, i, &rxframe);
+ bcm_rx_cmp_to_index(op, i, rxframe);
break;
}
}
- bcm_rx_starttimer(op);
}
+
+rx_freeskb_starttimer:
+ bcm_rx_starttimer(op);
+rx_freeskb:
+ kfree_skb(skb);
}
/*
@@ -681,6 +705,12 @@ static void bcm_remove_op(struct bcm_op *op)
hrtimer_cancel(&op->timer);
hrtimer_cancel(&op->thrtimer);
+ if (op->tsklet.func)
+ tasklet_kill(&op->tsklet);
+
+ if (op->thrtsklet.func)
+ tasklet_kill(&op->thrtsklet);
+
if ((op->frames) && (op->frames != &op->sframe))
kfree(op->frames);
@@ -891,6 +921,10 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
op->timer.function = bcm_tx_timeout_handler;
+ /* initialize tasklet for tx countevent notification */
+ tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet,
+ (unsigned long) op);
+
/* currently unused in tx_ops */
hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
@@ -1054,9 +1088,17 @@ static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
op->timer.function = bcm_rx_timeout_handler;
+ /* initialize tasklet for rx timeout notification */
+ tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet,
+ (unsigned long) op);
+
hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
op->thrtimer.function = bcm_rx_thr_handler;
+ /* initialize tasklet for rx throttle handling */
+ tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet,
+ (unsigned long) op);
+
/* add this bcm_op to the list of the rx_ops */
list_add(&op->list, &bo->rx_ops);
@@ -1102,7 +1144,7 @@ static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
*/
op->kt_lastmsg = ktime_set(0, 0);
hrtimer_cancel(&op->thrtimer);
- bcm_rx_thr_flush(op);
+ bcm_rx_thr_flush(op, 1);
}
if ((op->flags & STARTTIMER) && op->kt_ival1.tv64)