1 files changed, 130 insertions, 121 deletions

diff --git a/net/can/bcm.c b/net/can/bcm.c
index e9f99b2c6bc9..74fd2d33aff4 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -43,6 +43,7 @@
 
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/hrtimer.h>
 #include <linux/list.h>
 #include <linux/proc_fs.h>
 #include <linux/uio.h>
@@ -66,7 +67,7 @@
 #define REGMASK(id) ((id & CAN_RTR_FLAG) | ((id & CAN_EFF_FLAG) ? \
 			(CAN_EFF_MASK | CAN_EFF_FLAG) : CAN_SFF_MASK))
 
-#define CAN_BCM_VERSION CAN_VERSION
+#define CAN_BCM_VERSION "20080415"
 static __initdata const char banner[] = KERN_INFO
 	"can: broadcast manager protocol (rev " CAN_BCM_VERSION ")\n";
 
@@ -85,11 +86,10 @@ struct bcm_op {
 	int ifindex;
 	canid_t can_id;
 	int flags;
-	unsigned long j_ival1, j_ival2, j_lastmsg;
 	unsigned long frames_abs, frames_filtered;
-	struct timer_list timer, thrtimer;
 	struct timeval ival1, ival2;
-	ktime_t rx_stamp;
+	struct hrtimer timer, thrtimer;
+	ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg;
 	int rx_ifindex;
 	int count;
 	int nframes;
@@ -126,39 +126,6 @@ static inline struct bcm_sock *bcm_sk(const struct sock *sk)
 #define MHSIZ sizeof(struct bcm_msg_head)
 
 /*
- * rounded_tv2jif - calculate jiffies from timeval including optional up
- * @tv: pointer to timeval
- *
- * Description:
- * Unlike timeval_to_jiffies() provided in include/linux/jiffies.h, this
- * function is intentionally more relaxed on precise timer ticks to get
- * exact one jiffy for requested 1000us on a 1000HZ machine.
- * This code is to be removed when upgrading to kernel hrtimer.
- *
- * Return:
- *  calculated jiffies (max: ULONG_MAX)
- */
-static unsigned long rounded_tv2jif(const struct timeval *tv)
-{
-	unsigned long sec  = tv->tv_sec;
-	unsigned long usec = tv->tv_usec;
-	unsigned long jif;
-
-	if (sec > ULONG_MAX / HZ)
-		return ULONG_MAX;
-
-	/* round up to get at least the requested time */
-	usec += 1000000 / HZ - 1;
-
-	jif  = usec / (1000000 / HZ);
-
-	if (sec * HZ > ULONG_MAX - jif)
-		return ULONG_MAX;
-
-	return jif + sec * HZ;
-}
-
-/*
  * procfs functions
  */
 static char *bcm_proc_getifname(int ifindex)
@@ -208,13 +175,17 @@ static int bcm_read_proc(char *page, char **start, off_t off,
 		len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ",
 				op->nframes,
 				(op->flags & RX_CHECK_DLC)?'d':' ');
-		if (op->j_ival1)
+		if (op->kt_ival1.tv64)
 			len += snprintf(page + len, PAGE_SIZE - len,
-					"timeo=%ld ", op->j_ival1);
+					"timeo=%lld ",
+					(long long)
+					ktime_to_us(op->kt_ival1));
 
-		if (op->j_ival2)
+		if (op->kt_ival2.tv64)
 			len += snprintf(page + len, PAGE_SIZE - len,
-					"thr=%ld ", op->j_ival2);
+					"thr=%lld ",
+					(long long)
+					ktime_to_us(op->kt_ival2));
 
 		len += snprintf(page + len, PAGE_SIZE - len,
 				"# recv %ld (%ld) => reduction: ",
@@ -238,13 +209,14 @@ static int bcm_read_proc(char *page, char **start, off_t off,
 				"tx_op: %03X %s [%d] ",
 				op->can_id, bcm_proc_getifname(op->ifindex),
 				op->nframes);
-		if (op->j_ival1)
-			len += snprintf(page + len, PAGE_SIZE - len, "t1=%ld ",
-					op->j_ival1);
 
-		if (op->j_ival2)
-			len += snprintf(page + len, PAGE_SIZE - len, "t2=%ld ",
-					op->j_ival2);
+		if (op->kt_ival1.tv64)
+			len += snprintf(page + len, PAGE_SIZE - len, "t1=%lld ",
+					(long long) ktime_to_us(op->kt_ival1));
+
+		if (op->kt_ival2.tv64)
+			len += snprintf(page + len, PAGE_SIZE - len, "t2=%lld ",
+					(long long) ktime_to_us(op->kt_ival2));
 
 		len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n",
 				op->frames_abs);
@@ -371,11 +343,12 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
 /*
  * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
  */
-static void bcm_tx_timeout_handler(unsigned long data)
+static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
 {
-	struct bcm_op *op = (struct bcm_op *)data;
+	struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
+	enum hrtimer_restart ret = HRTIMER_NORESTART;
 
-	if (op->j_ival1 && (op->count > 0)) {
+	if (op->kt_ival1.tv64 && (op->count > 0)) {
 
 		op->count--;
 		if (!op->count && (op->flags & TX_COUNTEVT)) {
@@ -394,22 +367,24 @@ static void bcm_tx_timeout_handler(unsigned long data)
 		}
 	}
 
-	if (op->j_ival1 && (op->count > 0)) {
+	if (op->kt_ival1.tv64 && (op->count > 0)) {
 
 		/* send (next) frame */
 		bcm_can_tx(op);
-		mod_timer(&op->timer, jiffies + op->j_ival1);
+		hrtimer_forward(hrtimer, ktime_get(), op->kt_ival1);
+		ret = HRTIMER_RESTART;
 
 	} else {
-		if (op->j_ival2) {
+		if (op->kt_ival2.tv64) {
 
 			/* send (next) frame */
 			bcm_can_tx(op);
-			mod_timer(&op->timer, jiffies + op->j_ival2);
+			hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
+			ret = HRTIMER_RESTART;
 		}
 	}
 
-	return;
+	return ret;
 }
 
 /*
@@ -419,8 +394,6 @@ static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
 {
 	struct bcm_msg_head head;
 
-	op->j_lastmsg = jiffies;
-
 	/* update statistics */
 	op->frames_filtered++;
 
@@ -439,6 +412,12 @@ static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
 	bcm_send_to_user(op, &head, data, 1);
 }
 
+/* TODO: move to linux/hrtimer.h */
+static inline int hrtimer_callback_running(struct hrtimer *timer)
+{
+        return timer->state & HRTIMER_STATE_CALLBACK;
+}
+
 /*
  * bcm_rx_update_and_send - process a detected relevant receive content change
  *                          1. update the last received data
@@ -448,30 +427,44 @@ static void bcm_rx_update_and_send(struct bcm_op *op,
 				   struct can_frame *lastdata,
 				   struct can_frame *rxdata)
 {
-	unsigned long nexttx = op->j_lastmsg + op->j_ival2;
-
 	memcpy(lastdata, rxdata, CFSIZ);
 
 	/* mark as used */
 	lastdata->can_dlc |= RX_RECV;
 
-	/* throttle bcm_rx_changed ? */
-	if ((op->thrtimer.expires) ||
-	    ((op->j_ival2) && (nexttx > jiffies))) {
-		/* we are already waiting OR we have to start waiting */
+	/* throtteling mode inactive OR data update already on the run ? */
+	if (!op->kt_ival2.tv64 || hrtimer_callback_running(&op->thrtimer)) {
+		/* send RX_CHANGED to the user immediately */
+		bcm_rx_changed(op, rxdata);
+		return;
+	}
 
+	if (hrtimer_active(&op->thrtimer)) {
 		/* mark as 'throttled' */
 		lastdata->can_dlc |= RX_THR;
+		return;
+	}
 
-		if (!(op->thrtimer.expires)) {
-			/* start the timer only the first time */
-			mod_timer(&op->thrtimer, nexttx);
-		}
-
-	} else {
-		/* send RX_CHANGED to the user immediately */
+	if (!op->kt_lastmsg.tv64) {
+		/* send first RX_CHANGED to the user immediately */
 		bcm_rx_changed(op, rxdata);
+		op->kt_lastmsg = ktime_get();
+		return;
+	}
+
+	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;
+		hrtimer_start(&op->thrtimer,
+			      ktime_add(op->kt_lastmsg, op->kt_ival2),
+			      HRTIMER_MODE_ABS);
+		return;
 	}
+
+	/* the gap was that big, that throttling was not needed here */
+	bcm_rx_changed(op, rxdata);
+	op->kt_lastmsg = ktime_get();
 }
 
 /*
@@ -519,16 +512,16 @@ static void bcm_rx_starttimer(struct bcm_op *op)
 	if (op->flags & RX_NO_AUTOTIMER)
 		return;
 
-	if (op->j_ival1)
-		mod_timer(&op->timer, jiffies + op->j_ival1);
+	if (op->kt_ival1.tv64)
+		hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
 }
 
 /*
  * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
  */
-static void bcm_rx_timeout_handler(unsigned long data)
+static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
 {
-	struct bcm_op *op = (struct bcm_op *)data;
+	struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
 	struct bcm_msg_head msg_head;
 
 	msg_head.opcode  = RX_TIMEOUT;
@@ -548,27 +541,27 @@ static void bcm_rx_timeout_handler(unsigned long data)
 		/* clear received can_frames to indicate 'nothing received' */
 		memset(op->last_frames, 0, op->nframes * CFSIZ);
 	}
+
+	return HRTIMER_NORESTART;
 }
 
 /*
- * bcm_rx_thr_handler - the time for blocked content updates is over now:
- *                      Check for throttled data and send it to the userspace
+ * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
  */
-static void bcm_rx_thr_handler(unsigned long data)
+static int bcm_rx_thr_flush(struct bcm_op *op)
 {
-	struct bcm_op *op = (struct bcm_op *)data;
-	int i = 0;
-
-	/* mark disabled / consumed timer */
-	op->thrtimer.expires = 0;
+	int updated = 0;
 
 	if (op->nframes > 1) {
+		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++;
 			}
 		}
 
@@ -577,8 +570,29 @@ static void bcm_rx_thr_handler(unsigned long data)
 		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++;
 		}
 	}
+
+	return updated;
+}
+
+/*
+ * bcm_rx_thr_handler - the time for blocked content updates is over now:
+ *                      Check for throttled data and send it to the userspace
+ */
+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)) {
+		hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
+		return HRTIMER_RESTART;
+	} else {
+		/* rearm throttle handling */
+		op->kt_lastmsg = ktime_set(0, 0);
+		return HRTIMER_NORESTART;
+	}
 }
 
 /*
@@ -591,7 +605,7 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data)
 	int i;
 
 	/* disable timeout */
-	del_timer(&op->timer);
+	hrtimer_cancel(&op->timer);
 
 	if (skb->len == sizeof(rxframe)) {
 		memcpy(&rxframe, skb->data, sizeof(rxframe));
@@ -669,8 +683,8 @@ static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
 
 static void bcm_remove_op(struct bcm_op *op)
 {
-	del_timer(&op->timer);
-	del_timer(&op->thrtimer);
+	hrtimer_cancel(&op->timer);
+	hrtimer_cancel(&op->thrtimer);
 
 	if ((op->frames) && (op->frames != &op->sframe))
 		kfree(op->frames);
@@ -871,11 +885,11 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 		op->ifindex = ifindex;
 
 		/* initialize uninitialized (kzalloc) structure */
-		setup_timer(&op->timer, bcm_tx_timeout_handler,
-			    (unsigned long)op);
+		hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		op->timer.function = bcm_tx_timeout_handler;
 
 		/* currently unused in tx_ops */
-		init_timer(&op->thrtimer);
+		hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 
 		/* add this bcm_op to the list of the tx_ops */
 		list_add(&op->list, &bo->tx_ops);
@@ -902,25 +916,27 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 		op->count = msg_head->count;
 		op->ival1 = msg_head->ival1;
 		op->ival2 = msg_head->ival2;
-		op->j_ival1 = rounded_tv2jif(&msg_head->ival1);
-		op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
+		op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
+		op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
 
 		/* disable an active timer due to zero values? */
-		if (!op->j_ival1 && !op->j_ival2)
-			del_timer(&op->timer);
+		if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64)
+			hrtimer_cancel(&op->timer);
 	}
 
 	if ((op->flags & STARTTIMER) &&
-	    ((op->j_ival1 && op->count) || op->j_ival2)) {
+	    ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) {
 
 		/* spec: send can_frame when starting timer */
 		op->flags |= TX_ANNOUNCE;
 
-		if (op->j_ival1 && (op->count > 0)) {
+		if (op->kt_ival1.tv64 && (op->count > 0)) {
 			/* op->count-- is done in bcm_tx_timeout_handler */
-			mod_timer(&op->timer, jiffies + op->j_ival1);
+			hrtimer_start(&op->timer, op->kt_ival1,
+				      HRTIMER_MODE_REL);
 		} else
-			mod_timer(&op->timer, jiffies + op->j_ival2);
+			hrtimer_start(&op->timer, op->kt_ival2,
+				      HRTIMER_MODE_REL);
 	}
 
 	if (op->flags & TX_ANNOUNCE)
@@ -1032,15 +1048,11 @@ static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 		op->ifindex = ifindex;
 
 		/* initialize uninitialized (kzalloc) structure */
-		setup_timer(&op->timer, bcm_rx_timeout_handler,
-			    (unsigned long)op);
+		hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		op->timer.function = bcm_rx_timeout_handler;
 
-		/* init throttle timer for RX_CHANGED */
-		setup_timer(&op->thrtimer, bcm_rx_thr_handler,
-			    (unsigned long)op);
-
-		/* mark disabled timer */
-		op->thrtimer.expires = 0;
+		hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		op->thrtimer.function = bcm_rx_thr_handler;
 
 		/* add this bcm_op to the list of the rx_ops */
 		list_add(&op->list, &bo->rx_ops);
@@ -1056,8 +1068,8 @@ static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 	if (op->flags & RX_RTR_FRAME) {
 
 		/* no timers in RTR-mode */
-		del_timer(&op->thrtimer);
-		del_timer(&op->timer);
+		hrtimer_cancel(&op->thrtimer);
+		hrtimer_cancel(&op->timer);
 
 		/*
 		 * funny feature in RX(!)_SETUP only for RTR-mode:
@@ -1074,28 +1086,25 @@ static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
 			/* set timer value */
 			op->ival1 = msg_head->ival1;
 			op->ival2 = msg_head->ival2;
-			op->j_ival1 = rounded_tv2jif(&msg_head->ival1);
-			op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
+			op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
+			op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
 
 			/* disable an active timer due to zero value? */
-			if (!op->j_ival1)
-				del_timer(&op->timer);
-
-			/* free currently blocked msgs ? */
-			if (op->thrtimer.expires) {
-				/* send blocked msgs hereafter */
-				mod_timer(&op->thrtimer, jiffies + 2);
-			}
+			if (!op->kt_ival1.tv64)
+				hrtimer_cancel(&op->timer);
 
 			/*
-			 * if (op->j_ival2) is zero, no (new) throttling
-			 * will happen. For details see functions
-			 * bcm_rx_update_and_send() and bcm_rx_thr_handler()
+			 * In any case cancel the throttle timer, flush
+			 * potentially blocked msgs and reset throttle handling
 			 */
+			op->kt_lastmsg = ktime_set(0, 0);
+			hrtimer_cancel(&op->thrtimer);
+			bcm_rx_thr_flush(op);
 		}
 
-		if ((op->flags & STARTTIMER) && op->j_ival1)
-			mod_timer(&op->timer, jiffies + op->j_ival1);
+		if ((op->flags & STARTTIMER) && op->kt_ival1.tv64)
+			hrtimer_start(&op->timer, op->kt_ival1,
+				      HRTIMER_MODE_REL);
 	}
 
 	/* now we can register for can_ids, if we added a new bcm_op */