[NET_SCHED]: Show timer resolution instead of clock resolution in /proc/net/psched

[NET_SCHED]: Show timer resolution instead of clock resolution in /proc/net/psched

[Patrick McHardy]

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Fix incorrect HTB burst rate calculation in userspace when
clock and timer resolution differ. I guess this should go
in stable 2.6.22/23 as well.


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[NET_SCHED]: Show timer resolution instead of clock resolution in /proc/net/psched

The fourth parameter of /proc/net/psched is supposed to show the timer resultion
and is used by HTB userspace to calculate the necessary burst rate. Currently
we show the clock resolution, which results in a too low burst rate when the
two differ.

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

---
commit a3885788169f2f70634f8142344e5131ccf32595
tree 62bcf28c9706547228521dc4402ebea273326331
parent 0e52ab8ceb41df2104279938484267ab474286d1
author Patrick McHardy <kaber@trash.net> Wed, 10 Oct 2007 16:29:14 +0200
committer Patrick McHardy <kaber@trash.net> Wed, 10 Oct 2007 16:29:14 +0200

 net/sched/sch_api.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index dee0d5f..8f1bcf6 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1225,10 +1225,13 @@ EXPORT_SYMBOL(tcf_destroy_chain);
 #ifdef CONFIG_PROC_FS
 static int psched_show(struct seq_file *seq, void *v)
 {
+	struct timespec ts;
+
+	hrtimer_get_res(CLOCK_MONOTONIC, &ts);
 	seq_printf(seq, "%08x %08x %08x %08x\n",
 		   (u32)NSEC_PER_USEC, (u32)PSCHED_US2NS(1),
 		   1000000,
-		   (u32)NSEC_PER_SEC/(u32)ktime_to_ns(KTIME_MONOTONIC_RES));
+		   (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts)));
 
 	return 0;
 }

Re: [NET_SCHED]: Show timer resolution instead of clock resolution in /proc/net/psched

[David Miller]

From: Patrick McHardy <kaber@trash.net>
Date: Wed, 10 Oct 2007 16:34:24 +0200

> [NET_SCHED]: Show timer resolution instead of clock resolution in /proc/net/psched
> 
> The fourth parameter of /proc/net/psched is supposed to show the timer resultion
> and is used by HTB userspace to calculate the necessary burst rate. Currently
> we show the clock resolution, which results in a too low burst rate when the
> two differ.
> 
> Signed-off-by: Patrick McHardy <kaber@trash.net>

Applied, thanks Patrick.