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SubjectRe: clockevent questions
Thomas,

On 5/12/07, Thomas Gleixner <tglx@linutronix.de> 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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