[RFC][PATCH 2/4] timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers

From: John Stultz
Date: Fri May 29 2015 - 16:25:12 EST


I noticed for non-monotonic timers in timer_list, some of the
output looked a little confusing.

For example:
#1: <0000000000000000>, posix_timer_fn, S:01, hrtimer_start_range_ns, leap-a-day/2360
# expires at 1434412800000000000-1434412800000000000 nsecs [in 1434410725062375469 to 1434410725062375469 nsecs]

You'll note the relative time till the expiration "[in xxx to
yyy nsecs]" is incorrect. This is because its printing the delta
between CLOCK_MONOTONIC time to the CLOCK_REALTIME expiration.

This patch fixes this issue by adding the clock offset to the
"now" time which we use to calculate the delta.

Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Cc: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Richard Cochran <richardcochran@xxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: Jiri Bohac <jbohac@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
kernel/time/timer_list.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index e878c2e..05a560f 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -132,7 +132,7 @@ print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)
(unsigned long long) ktime_to_ns(base->offset));
#endif
SEQ_printf(m, "active timers:\n");
- print_active_timers(m, base, now);
+ print_active_timers(m, base, now + ktime_to_ns(base->offset));
}

static void print_cpu(struct seq_file *m, int cpu, u64 now)
--
1.9.1

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