[RFC IPROUTE 00/05]: Time cleanups

[RFC IPROUTE 00/05]: Time cleanups

[Patrick McHardy]

I'm currently adding support for ktime as clocksource to the qdisc layer and
in the course of doing that cleaned up the iproute time handling a bit to
make it easier to use a different internal clock resultion and audit for
integer overflows.

Increasing iproutes internal clock resolution is necessary for all token bucket
based schedulers to take advantage of a higher kernel clock resolution because
the kernel only does lookups and additions/subtractions, which can never result
in values that have a higher precision that those passed from userspace.

The way I imagine it we have to keep the old clock sources around for userspace
compatibility since they can't deal with the higher precision values. iproute is
changed to use nsec internally and reads the kernel clock resulution from
/proc/net/psched (third value, currently assumed to always be 10^6) to convert
it's internal resolution to that of the kernel. With ktime as clocksource the
kernel will report a resulution of 10^9. The downside is that distributors can't
enable ktime unless they want to break compatibility with old iproute versions.
Any better suggestions are welcome of course.


 tc/m_estimator.c  |    4 ++--
 tc/m_police.c     |    2 +-
 tc/q_cbq.c        |   15 ++++++++-------
 tc/q_hfsc.c       |   18 +++++++++---------
 tc/q_htb.c        |    4 ++--
 tc/q_netem.c      |   12 +++---------
 tc/q_tbf.c        |   20 ++++++++++----------
 tc/tc_cbq.c       |    8 ++++----
 tc/tc_core.c      |   31 +++++++++++++++++++++++--------
 tc/tc_core.h      |    9 +++++++--
 tc/tc_estimator.c |    2 +-
 tc/tc_red.c       |    2 +-
 tc/tc_util.c      |   33 +++++++++++++++++++--------------
 tc/tc_util.h      |    7 ++++---
 14 files changed, 94 insertions(+), 73 deletions(-)

Patrick McHardy:
      [IPROUTE]: Use tc_calc_xmittime where appropriate
      [IPROUTE]: Introduce tc_calc_xmitsize and use where appropriate
      [IPROUTE]: Introduce TIME_UNITS_PER_SEC to represent internal clock resulution
      [IPROUTE]: Replace "usec" by "time" in function names
      [IPROUTE]: Add sprint_ticks() function and use in CBQ

[IPROUTE 01/05]: Use tc_calc_xmittime where appropriate

[Patrick McHardy]

[IPROUTE]: Use tc_calc_xmittime where appropriate

Replace expressions of the form "1000000 * size/rate" by tc_calc_xmittime().
The CBQ case deserves an extra comment: when called with bnwd=rate
tc_cbq_calc_maxidle behaves identical to tc_calc_xmittime, so use it
for clarity.

Signed-off-by: Patrick McHardy <kaber@trash.net>

---
commit c25b0a7730d72f266e46fee3cfd53ce9f2a15c2f
tree 39c6fbd3395e8a41170739d6cff8d3a00d31a915
parent 8f8a36487119a3cd1afe86a9649704aca088567b
author Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:02:46 +0200
committer Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:02:46 +0200

 tc/q_cbq.c   |    2 +-
 tc/q_tbf.c   |    4 ++--
 tc/tc_core.c |    2 +-
 tc/tc_red.c  |    2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/tc/q_cbq.c b/tc/q_cbq.c
index a456eda..045c377 100644
--- a/tc/q_cbq.c
+++ b/tc/q_cbq.c
@@ -147,7 +147,7 @@ static int cbq_parse_opt(struct qdisc_ut
 	if (ewma_log < 0)
 		ewma_log = TC_CBQ_DEF_EWMA;
 	lss.ewma_log = ewma_log;
-	lss.maxidle = tc_cbq_calc_maxidle(r.rate, r.rate, avpkt, lss.ewma_log, 0);
+	lss.maxidle = tc_calc_xmittime(r.rate, avpkt);
 	lss.change = TCF_CBQ_LSS_MAXIDLE|TCF_CBQ_LSS_EWMA|TCF_CBQ_LSS_AVPKT;
 	lss.avpkt = avpkt;
 
diff --git a/tc/q_tbf.c b/tc/q_tbf.c
index 6ed5e0b..87b1b29 100644
--- a/tc/q_tbf.c
+++ b/tc/q_tbf.c
@@ -245,9 +245,9 @@ static int tbf_print_opt(struct qdisc_ut
 	if (show_raw)
 		fprintf(f, "limit %s ", sprint_size(qopt->limit, b1));
 
-	latency = 1000000*(qopt->limit/(double)qopt->rate.rate) - tc_core_tick2usec(qopt->buffer);
+	latency = tc_calc_xmittime(qopt->rate.rate, qopt->limit) - tc_core_tick2usec(qopt->buffer);
 	if (qopt->peakrate.rate) {
-		double lat2 = 1000000*(qopt->limit/(double)qopt->peakrate.rate) - tc_core_tick2usec(qopt->mtu);
+		double lat2 = tc_calc_xmittime(qopt->peakrate.rate, qopt->limit) - tc_core_tick2usec(qopt->mtu);
 		if (lat2 > latency)
 			latency = lat2;
 	}
diff --git a/tc/tc_core.c b/tc/tc_core.c
index 07cf2fa..8688b63 100644
--- a/tc/tc_core.c
+++ b/tc/tc_core.c
@@ -67,7 +67,7 @@ int tc_calc_rtable(unsigned bps, __u32 *
 			sz += overhead;
 		if (sz < mpu)
 			sz = mpu;
-		rtab[i] = tc_core_usec2tick(1000000*((double)sz/bps));
+		rtab[i] = tc_calc_xmittime(bps, sz);
 	}
 	return cell_log;
 }
diff --git a/tc/tc_red.c b/tc/tc_red.c
index 385e7af..8f9bde0 100644
--- a/tc/tc_red.c
+++ b/tc/tc_red.c
@@ -71,7 +71,7 @@ int tc_red_eval_ewma(unsigned qmin, unsi
 
 int tc_red_eval_idle_damping(int Wlog, unsigned avpkt, unsigned bps, __u8 *sbuf)
 {
-	double xmit_time = tc_core_usec2tick(1000000*(double)avpkt/bps);
+	double xmit_time = tc_calc_xmittime(bps, avpkt);
 	double lW = -log(1.0 - 1.0/(1<<Wlog))/xmit_time;
 	double maxtime = 31/lW;
 	int clog;

[IPROUTE 02/05]: Introduce tc_calc_xmitsize and use where appropriate

[Patrick McHardy]

[IPROUTE]: Introduce tc_calc_xmitsize and use where appropriate

Add tc_calc_xmitsize() as complement to tc_calc_xmittime(), which calculates
the size than can be transmitted at a given rate during a given time.
Replace all expressions of the form "size = rate*tc_core_tick2usec(time))/1000000"
by tc_calc_xmitsize() calls.

Signed-off-by: Patrick McHardy <kaber@trash.net>

---
commit 06a5350c47d028448850788031625ac1961d722b
tree 23eb5f6dbbb4a864e524c048f006842733924c9e
parent c25b0a7730d72f266e46fee3cfd53ce9f2a15c2f
author Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:13:09 +0200
committer Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:13:09 +0200

 tc/m_police.c |    2 +-
 tc/q_htb.c    |    4 ++--
 tc/q_tbf.c    |    4 ++--
 tc/tc_core.c  |    5 +++++
 tc/tc_core.h  |    1 +
 5 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/tc/m_police.c b/tc/m_police.c
index 71adb59..c3d2eeb 100644
--- a/tc/m_police.c
+++ b/tc/m_police.c
@@ -334,7 +334,7 @@ #endif
 
 	fprintf(f, " police 0x%x ", p->index);
 	fprintf(f, "rate %s ", sprint_rate(p->rate.rate, b1));
-	buffer = ((double)p->rate.rate*tc_core_tick2usec(p->burst))/1000000;
+	buffer = tc_calc_xmitsize(p->rate.rate, p->burst);
 	fprintf(f, "burst %s ", sprint_size(buffer, b1));
 	fprintf(f, "mtu %s ", sprint_size(p->mtu, b1));
 	if (show_raw)
diff --git a/tc/q_htb.c b/tc/q_htb.c
index 828d4b1..9a7755f 100644
--- a/tc/q_htb.c
+++ b/tc/q_htb.c
@@ -259,9 +259,9 @@ static int htb_print_opt(struct qdisc_ut
 				fprintf(f, "quantum %d ", (int)hopt->quantum);
 		}
 	    fprintf(f, "rate %s ", sprint_rate(hopt->rate.rate, b1));
-	    buffer = ((double)hopt->rate.rate*tc_core_tick2usec(hopt->buffer))/1000000;
+	    buffer = tc_calc_xmitsize(hopt->rate.rate, hopt->buffer);
 	    fprintf(f, "ceil %s ", sprint_rate(hopt->ceil.rate, b1));
-	    cbuffer = ((double)hopt->ceil.rate*tc_core_tick2usec(hopt->cbuffer))/1000000;
+	    cbuffer = tc_calc_xmitsize(hopt->ceil.rate, hopt->cbuffer);
 	    if (show_details) {
 		fprintf(f, "burst %s/%u mpu %s overhead %s ",
 			sprint_size(buffer, b1),
diff --git a/tc/q_tbf.c b/tc/q_tbf.c
index 87b1b29..bb13d77 100644
--- a/tc/q_tbf.c
+++ b/tc/q_tbf.c
@@ -218,7 +218,7 @@ static int tbf_print_opt(struct qdisc_ut
 	if (RTA_PAYLOAD(tb[TCA_TBF_PARMS])  < sizeof(*qopt))
 		return -1;
 	fprintf(f, "rate %s ", sprint_rate(qopt->rate.rate, b1));
-	buffer = ((double)qopt->rate.rate*tc_core_tick2usec(qopt->buffer))/1000000;
+	buffer = tc_calc_xmitsize(qopt->rate.rate, qopt->buffer);
 	if (show_details) {
 		fprintf(f, "burst %s/%u mpu %s ", sprint_size(buffer, b1),
 			1<<qopt->rate.cell_log, sprint_size(qopt->rate.mpu, b2));
@@ -230,7 +230,7 @@ static int tbf_print_opt(struct qdisc_ut
 	if (qopt->peakrate.rate) {
 		fprintf(f, "peakrate %s ", sprint_rate(qopt->peakrate.rate, b1));
 		if (qopt->mtu || qopt->peakrate.mpu) {
-			mtu = ((double)qopt->peakrate.rate*tc_core_tick2usec(qopt->mtu))/1000000;
+			mtu = tc_calc_xmitsize(qopt->peakrate.rate, qopt->mtu);
 			if (show_details) {
 				fprintf(f, "mtu %s/%u mpu %s ", sprint_size(mtu, b1),
 					1<<qopt->peakrate.cell_log, sprint_size(qopt->peakrate.mpu, b2));
diff --git a/tc/tc_core.c b/tc/tc_core.c
index 8688b63..7d6dd7d 100644
--- a/tc/tc_core.c
+++ b/tc/tc_core.c
@@ -42,6 +42,11 @@ unsigned tc_calc_xmittime(unsigned rate,
 	return tc_core_usec2tick(1000000*((double)size/rate));
 }
 
+unsigned tc_calc_xmitsize(unsigned rate, unsigned ticks)
+{
+	return ((double)rate*tc_core_tick2usec(ticks))/1000000;
+}
+
 /*
    rtab[pkt_len>>cell_log] = pkt_xmit_time
  */
diff --git a/tc/tc_core.h b/tc/tc_core.h
index 1537f95..d97c011 100644
--- a/tc/tc_core.h
+++ b/tc/tc_core.h
@@ -7,6 +7,7 @@ #include <linux/pkt_sched.h>
 long tc_core_usec2tick(long usec);
 long tc_core_tick2usec(long tick);
 unsigned tc_calc_xmittime(unsigned rate, unsigned size);
+unsigned tc_calc_xmitsize(unsigned rate, unsigned ticks);
 int tc_calc_rtable(unsigned bps, __u32 *rtab, int cell_log, unsigned mtu, unsigned mpu);
 
 int tc_setup_estimator(unsigned A, unsigned time_const, struct tc_estimator *est);

[IPROUTE 03/05]: Introduce TIME_UNITS_PER_SEC to represent internal clock resulution

[Patrick McHardy]

[IPROUTE]: Introduce TIME_UNITS_PER_SEC to represent internal clock resulution

Introduce TIME_UNITS_PER_SEC and conversion functions between internal
resulution and resulution expected by the kernel (currently implemented as
NOPs, only needed by HFSC, which currently always uses microseconds).

Signed-off-by: Patrick McHardy <kaber@trash.net>

---
commit 8e2cc14ba6fb8f940de72f307e67eb9040a5d4f7
tree da8e068525029b6571f95e7eeffcbab901f2e1be
parent 06a5350c47d028448850788031625ac1961d722b
author Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:40:34 +0200
committer Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:40:34 +0200

 tc/q_hfsc.c       |   12 ++++++------
 tc/q_tbf.c        |    4 ++--
 tc/tc_cbq.c       |    4 ++--
 tc/tc_core.c      |   14 ++++++++++++--
 tc/tc_core.h      |    4 ++++
 tc/tc_estimator.c |    2 +-
 tc/tc_util.c      |   14 +++++++-------
 7 files changed, 34 insertions(+), 20 deletions(-)

diff --git a/tc/q_hfsc.c b/tc/q_hfsc.c
index f09c606..be0587f 100644
--- a/tc/q_hfsc.c
+++ b/tc/q_hfsc.c
@@ -226,7 +226,7 @@ hfsc_print_sc(FILE *f, char *name, struc
 
 	fprintf(f, "%s ", name);
 	fprintf(f, "m1 %s ", sprint_rate(sc->m1, b1));
-	fprintf(f, "d %s ", sprint_usecs(sc->d, b1));
+	fprintf(f, "d %s ", sprint_usecs(tc_core_ktime2time(sc->d), b1));
 	fprintf(f, "m2 %s ", sprint_rate(sc->m2, b1));
 }
 
@@ -320,7 +320,7 @@ hfsc_get_sc1(int *argcp, char ***argvp, 
 		return -1;
 
 	sc->m1 = m1;
-	sc->d  = d;
+	sc->d  = tc_core_time2ktime(d);
 	sc->m2 = m2;
 
 	*argvp = argv;
@@ -367,13 +367,13 @@ hfsc_get_sc2(int *argcp, char ***argvp, 
 		return -1;
 	}
 
-	if (dmax != 0 && ceil(umax * 1000000.0 / dmax) > rate) {
+	if (dmax != 0 && ceil(1.0 * umax * TIME_UNITS_PER_SEC / dmax) > rate) {
 		/*
 		 * concave curve, slope of first segment is umax/dmax,
 		 * intersection is at dmax
 		 */
-		sc->m1 = ceil(umax * 1000000.0 / dmax); /* in bps */
-		sc->d  = dmax;
+		sc->m1 = ceil(1.0 * umax * TIME_UNITS_PER_SEC / dmax); /* in bps */
+		sc->d  = tc_core_time2ktime(dmax);
 		sc->m2 = rate;
 	} else {
 		/*
@@ -381,7 +381,7 @@ hfsc_get_sc2(int *argcp, char ***argvp, 
 		 * is at dmax - umax / rate
 		 */
 		sc->m1 = 0;
-		sc->d  = ceil(dmax - umax * 1000000.0 / rate); /* in usec */
+		sc->d  = tc_core_time2ktime(ceil(dmax - umax * TIME_UNITS_PER_SEC / rate));
 		sc->m2 = rate;
 	}
 
diff --git a/tc/q_tbf.c b/tc/q_tbf.c
index bb13d77..f2ffb7e 100644
--- a/tc/q_tbf.c
+++ b/tc/q_tbf.c
@@ -161,9 +161,9 @@ static int tbf_parse_opt(struct qdisc_ut
 	}
 
 	if (opt.limit == 0) {
-		double lim = opt.rate.rate*(double)latency/1000000 + buffer;
+		double lim = opt.rate.rate*(double)latency/TIME_UNITS_PER_SEC + buffer;
 		if (opt.peakrate.rate) {
-			double lim2 = opt.peakrate.rate*(double)latency/1000000 + mtu;
+			double lim2 = opt.peakrate.rate*(double)latency/TIME_UNITS_PER_SEC + mtu;
 			if (lim2 < lim)
 				lim = lim2;
 		}
diff --git a/tc/tc_cbq.c b/tc/tc_cbq.c
index 0abcc9d..c7b3a2d 100644
--- a/tc/tc_cbq.c
+++ b/tc/tc_cbq.c
@@ -38,7 +38,7 @@ unsigned tc_cbq_calc_maxidle(unsigned bn
 		if (vxmt > maxidle)
 			maxidle = vxmt;
 	}
-	return tc_core_usec2tick(maxidle*(1<<ewma_log)*1000000);
+	return tc_core_usec2tick(maxidle*(1<<ewma_log)*TIME_UNITS_PER_SEC);
 }
 
 unsigned tc_cbq_calc_offtime(unsigned bndw, unsigned rate, unsigned avpkt,
@@ -53,5 +53,5 @@ unsigned tc_cbq_calc_offtime(unsigned bn
 		offtime *= pow(g, -(double)minburst) - 1;
 	else
 		offtime *= 1 + (pow(g, -(double)(minburst-1)) - 1)/(1-g);
-	return tc_core_usec2tick(offtime*1000000);
+	return tc_core_usec2tick(offtime*TIME_UNITS_PER_SEC);
 }
diff --git a/tc/tc_core.c b/tc/tc_core.c
index 7d6dd7d..cf49d83 100644
--- a/tc/tc_core.c
+++ b/tc/tc_core.c
@@ -37,14 +37,24 @@ long tc_core_tick2usec(long tick)
 	return tick/tick_in_usec;
 }
 
+long tc_core_time2ktime(long time)
+{
+	return time;
+}
+
+long tc_core_ktime2time(long ktime)
+{
+	return ktime;
+}
+
 unsigned tc_calc_xmittime(unsigned rate, unsigned size)
 {
-	return tc_core_usec2tick(1000000*((double)size/rate));
+	return tc_core_usec2tick(TIME_UNITS_PER_SEC*((double)size/rate));
 }
 
 unsigned tc_calc_xmitsize(unsigned rate, unsigned ticks)
 {
-	return ((double)rate*tc_core_tick2usec(ticks))/1000000;
+	return ((double)rate*tc_core_tick2usec(ticks))/TIME_UNITS_PER_SEC;
 }
 
 /*
diff --git a/tc/tc_core.h b/tc/tc_core.h
index d97c011..720b6d6 100644
--- a/tc/tc_core.h
+++ b/tc/tc_core.h
@@ -4,8 +4,12 @@ #define _TC_CORE_H_ 1
 #include <asm/types.h>
 #include <linux/pkt_sched.h>
 
+#define TIME_UNITS_PER_SEC		1000000
+
 long tc_core_usec2tick(long usec);
 long tc_core_tick2usec(long tick);
+long tc_core_time2ktime(long time);
+long tc_core_ktime2time(long ktime);
 unsigned tc_calc_xmittime(unsigned rate, unsigned size);
 unsigned tc_calc_xmitsize(unsigned rate, unsigned ticks);
 int tc_calc_rtable(unsigned bps, __u32 *rtab, int cell_log, unsigned mtu, unsigned mpu);
diff --git a/tc/tc_estimator.c b/tc/tc_estimator.c
index 434db0f..e559add 100644
--- a/tc/tc_estimator.c
+++ b/tc/tc_estimator.c
@@ -26,7 +26,7 @@ #include "tc_core.h"
 int tc_setup_estimator(unsigned A, unsigned time_const, struct tc_estimator *est)
 {
 	for (est->interval=0; est->interval<=5; est->interval++) {
-		if (A <= (1<<est->interval)*(1000000/4))
+		if (A <= (1<<est->interval)*(TIME_UNITS_PER_SEC/4))
 			break;
 	}
 	if (est->interval > 5)
diff --git a/tc/tc_util.c b/tc/tc_util.c
index 9cde144..2ceb631 100644
--- a/tc/tc_util.c
+++ b/tc/tc_util.c
@@ -221,13 +221,13 @@ int get_usecs(unsigned *usecs, const cha
 	if (*p) {
 		if (strcasecmp(p, "s") == 0 || strcasecmp(p, "sec")==0 ||
 		    strcasecmp(p, "secs")==0)
-			t *= 1000000;
+			t *= TIME_UNITS_PER_SEC;
 		else if (strcasecmp(p, "ms") == 0 || strcasecmp(p, "msec")==0 ||
 			 strcasecmp(p, "msecs") == 0)
-			t *= 1000;
+			t *= TIME_UNITS_PER_SEC/1000;
 		else if (strcasecmp(p, "us") == 0 || strcasecmp(p, "usec")==0 ||
 			 strcasecmp(p, "usecs") == 0)
-			t *= 1;
+			t *= TIME_UNITS_PER_SEC/1000000;
 		else
 			return -1;
 	}
@@ -241,10 +241,10 @@ void print_usecs(char *buf, int len, __u
 {
 	double tmp = usec;
 
-	if (tmp >= 1000000)
-		snprintf(buf, len, "%.1fs", tmp/1000000);
-	else if (tmp >= 1000)
-		snprintf(buf, len, "%.1fms", tmp/1000);
+	if (tmp >= TIME_UNITS_PER_SEC)
+		snprintf(buf, len, "%.1fs", tmp/TIME_UNITS_PER_SEC);
+	else if (tmp >= TIME_UNITS_PER_SEC/1000)
+		snprintf(buf, len, "%.1fms", tmp/(TIME_UNITS_PER_SEC/1000));
 	else
 		snprintf(buf, len, "%uus", usec);
 }

[IPROUTE 04/05]: Replace "usec" by "time" in function names

[Patrick McHardy]

[IPROUTE]: Replace "usec" by "time" in function names

Rename functions containing "usec" since they don't necessarily return
usec units anymore.

Signed-off-by: Patrick McHardy <kaber@trash.net>

---
commit 67edfb2c86323a1c52a60538f677310f6c75efdf
tree 37302dfd036340aac8c7f2070ebcbc570fd634ed
parent 8e2cc14ba6fb8f940de72f307e67eb9040a5d4f7
author Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:47:14 +0200
committer Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:47:14 +0200

 tc/m_estimator.c |    4 ++--
 tc/q_cbq.c       |    6 +++---
 tc/q_hfsc.c      |    6 +++---
 tc/q_netem.c     |    6 +++---
 tc/q_tbf.c       |    8 ++++----
 tc/tc_cbq.c      |    4 ++--
 tc/tc_core.c     |   10 +++++-----
 tc/tc_core.h     |    4 ++--
 tc/tc_util.c     |   14 +++++++-------
 tc/tc_util.h     |    6 +++---
 10 files changed, 34 insertions(+), 34 deletions(-)

diff --git a/tc/m_estimator.c b/tc/m_estimator.c
index 78eda7a..898ff80 100644
--- a/tc/m_estimator.c
+++ b/tc/m_estimator.c
@@ -45,12 +45,12 @@ int parse_estimator(int *p_argc, char **
 		duparg("estimator", *argv);
 	if (matches(*argv, "help") == 0)
 		est_help();
-	if (get_usecs(&A, *argv))
+	if (get_time(&A, *argv))
 		invarg("estimator", "invalid estimator interval");
 	NEXT_ARG();
 	if (matches(*argv, "help") == 0)
 		est_help();
-	if (get_usecs(&time_const, *argv))
+	if (get_time(&time_const, *argv))
 		invarg("estimator", "invalid estimator time constant");
 	if (tc_setup_estimator(A, time_const, est) < 0) {
 		fprintf(stderr, "Error: estimator parameters are out of range.\n");
diff --git a/tc/q_cbq.c b/tc/q_cbq.c
index 045c377..648acd0 100644
--- a/tc/q_cbq.c
+++ b/tc/q_cbq.c
@@ -500,17 +500,17 @@ static int cbq_print_opt(struct qdisc_ut
 	if (lss && show_details) {
 		fprintf(f, "\nlevel %u ewma %u avpkt %ub ", lss->level, lss->ewma_log, lss->avpkt);
 		if (lss->maxidle) {
-			fprintf(f, "maxidle %luus ", tc_core_tick2usec(lss->maxidle>>lss->ewma_log));
+			fprintf(f, "maxidle %luus ", tc_core_tick2time(lss->maxidle>>lss->ewma_log));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->maxidle);
 		}
 		if (lss->minidle!=0x7fffffff) {
-			fprintf(f, "minidle %luus ", tc_core_tick2usec(lss->minidle>>lss->ewma_log));
+			fprintf(f, "minidle %luus ", tc_core_tick2time(lss->minidle>>lss->ewma_log));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->minidle);
 		}
 		if (lss->offtime) {
-			fprintf(f, "offtime %luus ", tc_core_tick2usec(lss->offtime));
+			fprintf(f, "offtime %luus ", tc_core_tick2time(lss->offtime));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->offtime);
 		}
diff --git a/tc/q_hfsc.c b/tc/q_hfsc.c
index be0587f..6c160c9 100644
--- a/tc/q_hfsc.c
+++ b/tc/q_hfsc.c
@@ -226,7 +226,7 @@ hfsc_print_sc(FILE *f, char *name, struc
 
 	fprintf(f, "%s ", name);
 	fprintf(f, "m1 %s ", sprint_rate(sc->m1, b1));
-	fprintf(f, "d %s ", sprint_usecs(tc_core_ktime2time(sc->d), b1));
+	fprintf(f, "d %s ", sprint_time(tc_core_ktime2time(sc->d), b1));
 	fprintf(f, "m2 %s ", sprint_rate(sc->m2, b1));
 }
 
@@ -303,7 +303,7 @@ hfsc_get_sc1(int *argcp, char ***argvp, 
 
 	if (matches(*argv, "d") == 0) {
 		NEXT_ARG();
-		if (get_usecs(&d, *argv) < 0) {
+		if (get_time(&d, *argv) < 0) {
 			explain1("d");
 			return -1;
 		}
@@ -346,7 +346,7 @@ hfsc_get_sc2(int *argcp, char ***argvp, 
 
 	if (matches(*argv, "dmax") == 0) {
 		NEXT_ARG();
-		if (get_usecs(&dmax, *argv) < 0) {
+		if (get_time(&dmax, *argv) < 0) {
 			explain1("dmax");
 			return -1;
 		}
diff --git a/tc/q_netem.c b/tc/q_netem.c
index 757edca..cc16a28 100644
--- a/tc/q_netem.c
+++ b/tc/q_netem.c
@@ -108,16 +108,16 @@ static int get_ticks(__u32 *ticks, const
 {
 	unsigned t;
 
-	if(get_usecs(&t, str))
+	if(get_time(&t, str))
 		return -1;
 	
-	*ticks = tc_core_usec2tick(t);
+	*ticks = tc_core_time2tick(t);
 	return 0;
 }
 
 static char *sprint_ticks(__u32 ticks, char *buf)
 {
-	return sprint_usecs(tc_core_tick2usec(ticks), buf);
+	return sprint_time(tc_core_tick2time(ticks), buf);
 }
 
 
diff --git a/tc/q_tbf.c b/tc/q_tbf.c
index f2ffb7e..4db4b44 100644
--- a/tc/q_tbf.c
+++ b/tc/q_tbf.c
@@ -67,7 +67,7 @@ static int tbf_parse_opt(struct qdisc_ut
 				fprintf(stderr, "Double \"limit/latency\" spec\n");
 				return -1;
 			}
-			if (get_usecs(&latency, *argv)) {
+			if (get_time(&latency, *argv)) {
 				explain1("latency");
 				return -1;
 			}
@@ -245,13 +245,13 @@ static int tbf_print_opt(struct qdisc_ut
 	if (show_raw)
 		fprintf(f, "limit %s ", sprint_size(qopt->limit, b1));
 
-	latency = tc_calc_xmittime(qopt->rate.rate, qopt->limit) - tc_core_tick2usec(qopt->buffer);
+	latency = tc_calc_xmittime(qopt->rate.rate, qopt->limit) - tc_core_tick2time(qopt->buffer);
 	if (qopt->peakrate.rate) {
-		double lat2 = tc_calc_xmittime(qopt->peakrate.rate, qopt->limit) - tc_core_tick2usec(qopt->mtu);
+		double lat2 = tc_calc_xmittime(qopt->peakrate.rate, qopt->limit) - tc_core_tick2time(qopt->mtu);
 		if (lat2 > latency)
 			latency = lat2;
 	}
-	fprintf(f, "lat %s ", sprint_usecs(tc_core_tick2usec(latency), b1));
+	fprintf(f, "lat %s ", sprint_time(tc_core_tick2time(latency), b1));
 
 	return 0;
 }
diff --git a/tc/tc_cbq.c b/tc/tc_cbq.c
index c7b3a2d..0bb262e 100644
--- a/tc/tc_cbq.c
+++ b/tc/tc_cbq.c
@@ -38,7 +38,7 @@ unsigned tc_cbq_calc_maxidle(unsigned bn
 		if (vxmt > maxidle)
 			maxidle = vxmt;
 	}
-	return tc_core_usec2tick(maxidle*(1<<ewma_log)*TIME_UNITS_PER_SEC);
+	return tc_core_time2tick(maxidle*(1<<ewma_log)*TIME_UNITS_PER_SEC);
 }
 
 unsigned tc_cbq_calc_offtime(unsigned bndw, unsigned rate, unsigned avpkt,
@@ -53,5 +53,5 @@ unsigned tc_cbq_calc_offtime(unsigned bn
 		offtime *= pow(g, -(double)minburst) - 1;
 	else
 		offtime *= 1 + (pow(g, -(double)(minburst-1)) - 1)/(1-g);
-	return tc_core_usec2tick(offtime*TIME_UNITS_PER_SEC);
+	return tc_core_time2tick(offtime*TIME_UNITS_PER_SEC);
 }
diff --git a/tc/tc_core.c b/tc/tc_core.c
index cf49d83..063995c 100644
--- a/tc/tc_core.c
+++ b/tc/tc_core.c
@@ -27,12 +27,12 @@ static __u32 t2us=1;
 static __u32 us2t=1;
 static double tick_in_usec = 1;
 
-long tc_core_usec2tick(long usec)
+long tc_core_time2tick(long time)
 {
-	return usec*tick_in_usec;
+	return time*tick_in_usec;
 }
 
-long tc_core_tick2usec(long tick)
+long tc_core_tick2time(long tick)
 {
 	return tick/tick_in_usec;
 }
@@ -49,12 +49,12 @@ long tc_core_ktime2time(long ktime)
 
 unsigned tc_calc_xmittime(unsigned rate, unsigned size)
 {
-	return tc_core_usec2tick(TIME_UNITS_PER_SEC*((double)size/rate));
+	return tc_core_time2tick(TIME_UNITS_PER_SEC*((double)size/rate));
 }
 
 unsigned tc_calc_xmitsize(unsigned rate, unsigned ticks)
 {
-	return ((double)rate*tc_core_tick2usec(ticks))/TIME_UNITS_PER_SEC;
+	return ((double)rate*tc_core_tick2time(ticks))/TIME_UNITS_PER_SEC;
 }
 
 /*
diff --git a/tc/tc_core.h b/tc/tc_core.h
index 720b6d6..52954be 100644
--- a/tc/tc_core.h
+++ b/tc/tc_core.h
@@ -6,8 +6,8 @@ #include <linux/pkt_sched.h>
 
 #define TIME_UNITS_PER_SEC		1000000
 
-long tc_core_usec2tick(long usec);
-long tc_core_tick2usec(long tick);
+long tc_core_time2tick(long time);
+long tc_core_tick2time(long tick);
 long tc_core_time2ktime(long time);
 long tc_core_ktime2time(long ktime);
 unsigned tc_calc_xmittime(unsigned rate, unsigned size);
diff --git a/tc/tc_util.c b/tc/tc_util.c
index 2ceb631..321bac0 100644
--- a/tc/tc_util.c
+++ b/tc/tc_util.c
@@ -209,7 +209,7 @@ char * sprint_rate(__u32 rate, char *buf
 	return buf;
 }
 
-int get_usecs(unsigned *usecs, const char *str)
+int get_time(unsigned *time, const char *str)
 {
 	double t;
 	char *p;
@@ -232,26 +232,26 @@ int get_usecs(unsigned *usecs, const cha
 			return -1;
 	}
 
-	*usecs = t;
+	*time = t;
 	return 0;
 }
 
 
-void print_usecs(char *buf, int len, __u32 usec)
+void print_time(char *buf, int len, __u32 time)
 {
-	double tmp = usec;
+	double tmp = time;
 
 	if (tmp >= TIME_UNITS_PER_SEC)
 		snprintf(buf, len, "%.1fs", tmp/TIME_UNITS_PER_SEC);
 	else if (tmp >= TIME_UNITS_PER_SEC/1000)
 		snprintf(buf, len, "%.1fms", tmp/(TIME_UNITS_PER_SEC/1000));
 	else
-		snprintf(buf, len, "%uus", usec);
+		snprintf(buf, len, "%uus", time);
 }
 
-char * sprint_usecs(__u32 usecs, char *buf)
+char * sprint_time(__u32 time, char *buf)
 {
-	print_usecs(buf, SPRINT_BSIZE-1, usecs);
+	print_time(buf, SPRINT_BSIZE-1, time);
 	return buf;
 }
 
diff --git a/tc/tc_util.h b/tc/tc_util.h
index 1aa1bda..aba4adb 100644
--- a/tc/tc_util.h
+++ b/tc/tc_util.h
@@ -46,17 +46,17 @@ extern int get_rate(unsigned *rate, cons
 extern int get_percent(unsigned *percent, const char *str);
 extern int get_size(unsigned *size, const char *str);
 extern int get_size_and_cell(unsigned *size, int *cell_log, char *str);
-extern int get_usecs(unsigned *usecs, const char *str);
+extern int get_time(unsigned *time, const char *str);
 extern void print_rate(char *buf, int len, __u32 rate);
 extern void print_size(char *buf, int len, __u32 size);
 extern void print_percent(char *buf, int len, __u32 percent);
 extern void print_qdisc_handle(char *buf, int len, __u32 h);
-extern void print_usecs(char *buf, int len, __u32 usecs);
+extern void print_time(char *buf, int len, __u32 time);
 extern char * sprint_rate(__u32 rate, char *buf);
 extern char * sprint_size(__u32 size, char *buf);
 extern char * sprint_qdisc_handle(__u32 h, char *buf);
 extern char * sprint_tc_classid(__u32 h, char *buf);
-extern char * sprint_usecs(__u32 usecs, char *buf);
+extern char * sprint_time(__u32 time, char *buf);
 extern char * sprint_percent(__u32 percent, char *buf);
 
 extern void print_tcstats_attr(FILE *fp, struct rtattr *tb[], char *prefix, struct rtattr **xstats);

[IPROUTE 05/05]: Add sprint_ticks() function and use in CBQ

[Patrick McHardy]

[IPROUTE]: Add sprint_ticks() function and use in CBQ

Add helper function to print ticks to avoid assumptions about clock
resolution in CBQ.

Signed-off-by: Patrick McHardy <kaber@trash.net>

---
commit 182666ac89f3089a1771564620998fb4f315bd87
tree ce7c3109b7e8ff9a4665e175490a62f8c300ea33
parent 67edfb2c86323a1c52a60538f677310f6c75efdf
author Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:52:11 +0200
committer Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:52:11 +0200

 tc/q_cbq.c   |    7 ++++---
 tc/q_netem.c |    6 ------
 tc/tc_util.c |    5 +++++
 tc/tc_util.h |    1 +
 4 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/tc/q_cbq.c b/tc/q_cbq.c
index 648acd0..abf0468 100644
--- a/tc/q_cbq.c
+++ b/tc/q_cbq.c
@@ -418,6 +418,7 @@ static int cbq_print_opt(struct qdisc_ut
 	struct tc_cbq_wrropt *wrr = NULL;
 	struct tc_cbq_fopt *fopt = NULL;
 	struct tc_cbq_ovl *ovl = NULL;
+	SPRINT_BUF(b1);
 
 	if (opt == NULL)
 		return 0;
@@ -500,17 +501,17 @@ static int cbq_print_opt(struct qdisc_ut
 	if (lss && show_details) {
 		fprintf(f, "\nlevel %u ewma %u avpkt %ub ", lss->level, lss->ewma_log, lss->avpkt);
 		if (lss->maxidle) {
-			fprintf(f, "maxidle %luus ", tc_core_tick2time(lss->maxidle>>lss->ewma_log));
+			fprintf(f, "maxidle %s ", sprint_ticks(lss->maxidle>>lss->ewma_log, b1));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->maxidle);
 		}
 		if (lss->minidle!=0x7fffffff) {
-			fprintf(f, "minidle %luus ", tc_core_tick2time(lss->minidle>>lss->ewma_log));
+			fprintf(f, "minidle %s ", sprint_ticks(lss->minidle>>lss->ewma_log, b1));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->minidle);
 		}
 		if (lss->offtime) {
-			fprintf(f, "offtime %luus ", tc_core_tick2time(lss->offtime));
+			fprintf(f, "offtime %s ", sprint_ticks(lss->offtime, b1));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->offtime);
 		}
diff --git a/tc/q_netem.c b/tc/q_netem.c
index cc16a28..0d7f4d5 100644
--- a/tc/q_netem.c
+++ b/tc/q_netem.c
@@ -115,12 +115,6 @@ static int get_ticks(__u32 *ticks, const
 	return 0;
 }
 
-static char *sprint_ticks(__u32 ticks, char *buf)
-{
-	return sprint_time(tc_core_tick2time(ticks), buf);
-}
-
-
 static int netem_parse_opt(struct qdisc_util *qu, int argc, char **argv, 
 			   struct nlmsghdr *n)
 {
diff --git a/tc/tc_util.c b/tc/tc_util.c
index 321bac0..c1e02f4 100644
--- a/tc/tc_util.c
+++ b/tc/tc_util.c
@@ -255,6 +255,11 @@ char * sprint_time(__u32 time, char *buf
 	return buf;
 }
 
+char * sprint_ticks(__u32 ticks, char *buf)
+{
+	return sprint_time(tc_core_tick2time(ticks), buf);
+}
+
 int get_size(unsigned *size, const char *str)
 {
 	double sz;
diff --git a/tc/tc_util.h b/tc/tc_util.h
index aba4adb..17e7b99 100644
--- a/tc/tc_util.h
+++ b/tc/tc_util.h
@@ -57,6 +57,7 @@ extern char * sprint_size(__u32 size, ch
 extern char * sprint_qdisc_handle(__u32 h, char *buf);
 extern char * sprint_tc_classid(__u32 h, char *buf);
 extern char * sprint_time(__u32 time, char *buf);
+extern char * sprint_ticks(__u32 ticks, char *buf);
 extern char * sprint_percent(__u32 percent, char *buf);
 
 extern void print_tcstats_attr(FILE *fp, struct rtattr *tb[], char *prefix, struct rtattr **xstats);

Re: [RFC IPROUTE 00/05]: Time cleanups

[Patrick McHardy]

D'oh, got Stephen's address wrong. Please fix it (add 's' in front) in
replies to this thread.

Patrick McHardy wrote:
> I'm currently adding support for ktime as clocksource to the qdisc layer and
> in the course of doing that cleaned up the iproute time handling a bit to
> make it easier to use a different internal clock resultion and audit for
> integer overflows.
> 
> Increasing iproutes internal clock resolution is necessary for all token bucket
> based schedulers to take advantage of a higher kernel clock resolution because
> the kernel only does lookups and additions/subtractions, which can never result
> in values that have a higher precision that those passed from userspace.
> 
> The way I imagine it we have to keep the old clock sources around for userspace
> compatibility since they can't deal with the higher precision values. iproute is
> changed to use nsec internally and reads the kernel clock resulution from
> /proc/net/psched (third value, currently assumed to always be 10^6) to convert
> it's internal resolution to that of the kernel. With ktime as clocksource the
> kernel will report a resulution of 10^9. The downside is that distributors can't
> enable ktime unless they want to break compatibility with old iproute versions.
> Any better suggestions are welcome of course.
> 
> 
>  tc/m_estimator.c  |    4 ++--
>  tc/m_police.c     |    2 +-
>  tc/q_cbq.c        |   15 ++++++++-------
>  tc/q_hfsc.c       |   18 +++++++++---------
>  tc/q_htb.c        |    4 ++--
>  tc/q_netem.c      |   12 +++---------
>  tc/q_tbf.c        |   20 ++++++++++----------
>  tc/tc_cbq.c       |    8 ++++----
>  tc/tc_core.c      |   31 +++++++++++++++++++++++--------
>  tc/tc_core.h      |    9 +++++++--
>  tc/tc_estimator.c |    2 +-
>  tc/tc_red.c       |    2 +-
>  tc/tc_util.c      |   33 +++++++++++++++++++--------------
>  tc/tc_util.h      |    7 ++++---
>  14 files changed, 94 insertions(+), 73 deletions(-)
> 
> Patrick McHardy:
>       [IPROUTE]: Use tc_calc_xmittime where appropriate
>       [IPROUTE]: Introduce tc_calc_xmitsize and use where appropriate
>       [IPROUTE]: Introduce TIME_UNITS_PER_SEC to represent internal clock resulution
>       [IPROUTE]: Replace "usec" by "time" in function names
>       [IPROUTE]: Add sprint_ticks() function and use in CBQ

Re: [IPROUTE 01/05]: Use tc_calc_xmittime where appropriate

[Patrick McHardy]

[-- Attachment #1: Type: text/plain, Size: 966 bytes --]

Patrick McHardy wrote:
> [IPROUTE]: Use tc_calc_xmittime where appropriate
> 
> diff --git a/tc/q_tbf.c b/tc/q_tbf.c
> index 6ed5e0b..87b1b29 100644
> --- a/tc/q_tbf.c
> +++ b/tc/q_tbf.c
> @@ -245,9 +245,9 @@ static int tbf_print_opt(struct qdisc_ut
>  	if (show_raw)
>  		fprintf(f, "limit %s ", sprint_size(qopt->limit, b1));
>  
> -	latency = 1000000*(qopt->limit/(double)qopt->rate.rate) - tc_core_tick2usec(qopt->buffer);
> +	latency = tc_calc_xmittime(qopt->rate.rate, qopt->limit) - tc_core_tick2usec(qopt->buffer);
>  	if (qopt->peakrate.rate) {
> -		double lat2 = 1000000*(qopt->limit/(double)qopt->peakrate.rate) - tc_core_tick2usec(qopt->mtu);
> +		double lat2 = tc_calc_xmittime(qopt->peakrate.rate, qopt->limit) - tc_core_tick2usec(qopt->mtu);
>  		if (lat2 > latency)


I think I should start reviewing my own patches in a mail client :)
The two cases above are wrong, tc_calc_xmittime does an additional
tc_core_usec2tick(). Corrected patch attached.

[-- Attachment #2: 01.diff --]
[-- Type: text/plain, Size: 2034 bytes --]

[IPROUTE]: Use tc_calc_xmittime where appropriate

Replace expressions of the form "1000000 * size/rate" by tc_calc_xmittime().
The CBQ case deserves an extra comment: when called with bnwd=rate
tc_cbq_calc_maxidle behaves identical to tc_calc_xmittime, so use it
for clarity.

Signed-off-by: Patrick McHardy <kaber@trash.net>

---
commit c25b0a7730d72f266e46fee3cfd53ce9f2a15c2f
tree 39c6fbd3395e8a41170739d6cff8d3a00d31a915
parent 8f8a36487119a3cd1afe86a9649704aca088567b
author Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:02:46 +0200
committer Patrick McHardy <kaber@trash.net> Fri, 23 Jun 2006 19:02:46 +0200

 tc/q_cbq.c   |    2 +-
 tc/q_tbf.c   |    4 ++--
 tc/tc_core.c |    2 +-
 tc/tc_red.c  |    2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/tc/q_cbq.c b/tc/q_cbq.c
index a456eda..045c377 100644
--- a/tc/q_cbq.c
+++ b/tc/q_cbq.c
@@ -147,7 +147,7 @@ static int cbq_parse_opt(struct qdisc_ut
 	if (ewma_log < 0)
 		ewma_log = TC_CBQ_DEF_EWMA;
 	lss.ewma_log = ewma_log;
-	lss.maxidle = tc_cbq_calc_maxidle(r.rate, r.rate, avpkt, lss.ewma_log, 0);
+	lss.maxidle = tc_calc_xmittime(r.rate, avpkt);
 	lss.change = TCF_CBQ_LSS_MAXIDLE|TCF_CBQ_LSS_EWMA|TCF_CBQ_LSS_AVPKT;
 	lss.avpkt = avpkt;
 
diff --git a/tc/tc_core.c b/tc/tc_core.c
index 07cf2fa..8688b63 100644
--- a/tc/tc_core.c
+++ b/tc/tc_core.c
@@ -67,7 +67,7 @@ int tc_calc_rtable(unsigned bps, __u32 *
 			sz += overhead;
 		if (sz < mpu)
 			sz = mpu;
-		rtab[i] = tc_core_usec2tick(1000000*((double)sz/bps));
+		rtab[i] = tc_calc_xmittime(bps, sz);
 	}
 	return cell_log;
 }
diff --git a/tc/tc_red.c b/tc/tc_red.c
index 385e7af..8f9bde0 100644
--- a/tc/tc_red.c
+++ b/tc/tc_red.c
@@ -71,7 +71,7 @@ int tc_red_eval_ewma(unsigned qmin, unsi
 
 int tc_red_eval_idle_damping(int Wlog, unsigned avpkt, unsigned bps, __u8 *sbuf)
 {
-	double xmit_time = tc_core_usec2tick(1000000*(double)avpkt/bps);
+	double xmit_time = tc_calc_xmittime(bps, avpkt);
 	double lW = -log(1.0 - 1.0/(1<<Wlog))/xmit_time;
 	double maxtime = 31/lW;
 	int clog;

Re: [RFC IPROUTE 00/05]: Time cleanups

[David Miller]

From: Patrick McHardy <kaber@trash.net>
Date: Fri, 23 Jun 2006 20:09:18 +0200

> D'oh, got Stephen's address wrong. Please fix it (add 's' in front) in
> replies to this thread.

Stephen's also on vacation for a week, so it might be a while
until this stuff is integrated :)

[IPROUTE 05/05]: Add sprint_ticks() function and use in CBQ

[Patrick McHardy]

[IPROUTE]: Add sprint_ticks() function and use in CBQ

Add helper function to print ticks to avoid assumptions about clock
resolution in CBQ.

Signed-off-by: Patrick McHardy <kaber@trash.net>

---
commit 408fb739030c2667bbc02187018c9e504384cdec
tree 21d2f5117d7f6f1fe18b5e7b5fa1a0627d1b7efc
parent d1980613b2921fcc288858f4c63727f28ca49607
author Patrick McHardy <kaber@trash.net> Wed, 10 Jan 2007 10:43:03 +0100
committer Patrick McHardy <kaber@trash.net> Wed, 10 Jan 2007 10:43:03 +0100

 tc/q_cbq.c   |    7 ++++---
 tc/q_netem.c |    6 ------
 tc/tc_util.c |    5 +++++
 tc/tc_util.h |    1 +
 4 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/tc/q_cbq.c b/tc/q_cbq.c
index 913b26a..f2b4ce8 100644
--- a/tc/q_cbq.c
+++ b/tc/q_cbq.c
@@ -418,6 +418,7 @@ static int cbq_print_opt(struct qdisc_ut
 	struct tc_cbq_wrropt *wrr = NULL;
 	struct tc_cbq_fopt *fopt = NULL;
 	struct tc_cbq_ovl *ovl = NULL;
+	SPRINT_BUF(b1);
 
 	if (opt == NULL)
 		return 0;
@@ -500,17 +501,17 @@ static int cbq_print_opt(struct qdisc_ut
 	if (lss && show_details) {
 		fprintf(f, "\nlevel %u ewma %u avpkt %ub ", lss->level, lss->ewma_log, lss->avpkt);
 		if (lss->maxidle) {
-			fprintf(f, "maxidle %luus ", tc_core_tick2time(lss->maxidle>>lss->ewma_log));
+			fprintf(f, "maxidle %s ", sprint_ticks(lss->maxidle>>lss->ewma_log, b1));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->maxidle);
 		}
 		if (lss->minidle!=0x7fffffff) {
-			fprintf(f, "minidle %luus ", tc_core_tick2time(lss->minidle>>lss->ewma_log));
+			fprintf(f, "minidle %s ", sprint_ticks(lss->minidle>>lss->ewma_log, b1));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->minidle);
 		}
 		if (lss->offtime) {
-			fprintf(f, "offtime %luus ", tc_core_tick2time(lss->offtime));
+			fprintf(f, "offtime %s ", sprint_ticks(lss->offtime, b1));
 			if (show_raw)
 				fprintf(f, "[%08x] ", lss->offtime);
 		}
diff --git a/tc/q_netem.c b/tc/q_netem.c
index 24fb95e..94ce6bb 100644
--- a/tc/q_netem.c
+++ b/tc/q_netem.c
@@ -120,12 +120,6 @@ static int get_ticks(__u32 *ticks, const
 	return 0;
 }
 
-static char *sprint_ticks(__u32 ticks, char *buf)
-{
-	return sprint_usecs(tc_core_tick2usec(ticks), buf);
-}
-
-
 static int netem_parse_opt(struct qdisc_util *qu, int argc, char **argv,
 			   struct nlmsghdr *n)
 {
diff --git a/tc/tc_util.c b/tc/tc_util.c
index b73fae9..a7e4257 100644
--- a/tc/tc_util.c
+++ b/tc/tc_util.c
@@ -255,6 +255,11 @@ char * sprint_time(__u32 time, char *buf
 	return buf;
 }
 
+char * sprint_ticks(__u32 ticks, char *buf)
+{
+	return sprint_time(tc_core_tick2time(ticks), buf);
+}
+
 int get_size(unsigned *size, const char *str)
 {
 	double sz;
diff --git a/tc/tc_util.h b/tc/tc_util.h
index b713cf1..eade72d 100644
--- a/tc/tc_util.h
+++ b/tc/tc_util.h
@@ -57,6 +57,7 @@ extern char * sprint_size(__u32 size, ch
 extern char * sprint_qdisc_handle(__u32 h, char *buf);
 extern char * sprint_tc_classid(__u32 h, char *buf);
 extern char * sprint_time(__u32 time, char *buf);
+extern char * sprint_ticks(__u32 ticks, char *buf);
 extern char * sprint_percent(__u32 percent, char *buf);
 
 extern void print_tcstats_attr(FILE *fp, struct rtattr *tb[], char *prefix, struct rtattr **xstats);