Re: clockevent questions

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Thomas,

On 5/12/07, Thomas Gleixner <[email protected]> wrote:
Well, it ends up in hrtimer_interrupt() and the code there finds out,
that the next timer is not due right now, so it simply requests the same
(absolute) time event again, which is processed by the clock events code
and eventually limited to the max delta of the device again.


My timer is finally using the clockevent subsystem. Below is the
output of '/proc/timer_list':

cat /proc/timer_list
Timer List Version: v0.3
HRTIMER_MAX_CLOCK_BASES: 2
now at 64696544360531 nsecs

cpu: 0
clock 0:
 .index:      0
 .resolution: 1 nsecs
 .get_time:   ktime_get_real
 .offset:     1179151153000000000 nsecs
active timers:
clock 1:
 .index:      1
 .resolution: 1 nsecs
 .get_time:   ktime_get
 .offset:     0 nsecs
active timers:
#0: <c03fde10>, tick_sched_timer, S:01
# expires at 64696546875000 nsecs [in 2514469 nsecs]
 .expires_next   : 64696546875000 nsecs
 .hres_active    : 1
 .nr_events      : 16562163
 .nohz_mode      : 0
 .idle_tick      : 0 nsecs
 .tick_stopped   : 0
 .idle_jiffies   : 0
 .idle_calls     : 0
 .idle_sleeps    : 0
 .idle_entrytime : 0 nsecs
 .idle_sleeptime : 0 nsecs
 .last_jiffies   : 0
 .next_jiffies   : 0
 .idle_expires   : 0 nsecs
jiffies: 16485515


Tick Device: mode:     1
Clock Event Device: hrt
max_delta_ns:   2147483647
min_delta_ns:   1000
mult:           206158430
shift:          32
mode:           3
next_event:     64696546875000 nsecs
set_next_event: hrt_next_event
set_mode:       hrt_timer_setup
event_handler:  hrtimer_interrupt

My question is about the clock resolution field which is equal to 1ns.
How is this possible since my timer's frequency is only 100Mhz ?

My 2 cents, it looks like some tabs are missing when printing the list
of hrtimers of each clock...

Thanks
--
Francis
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