linux-toradex.git/kernel/time/clockevents.c, branch v2.6.30.6

clockevents: let set_mode() setup delta information

2009-01-16T11:27:39+00:00

Allow the set_mode() clockevent callback to decide and fill in delta
details such as shift, mult, max_delta_ns and min_delta_ns.

With this change the clockevent can be registered without delta details
which allows us to keep the parent clock disabled until the clockevent
gets setup using set_mode().

Letting set_mode() fill in or update delta details allows us to save
power by disabling the parent clock while the clockevent is unused.
This may however make the parent clock rate change, so next time the
clockevent gets enabled we need let set_mode() to update the detla
details accordingly. Doing it at registration time is not enough.

Furthermore, the delta details seem unused in the case of periodic-only
clockevent drivers, so this change also allows registration of such
drivers without the delta details filled in.

Signed-off-by: Magnus Damm 
Signed-off-by: Thomas Gleixner

cpumask: convert struct clock_event_device to cpumask pointers.

2008-12-13T10:50:26+00:00

Impact: change calling convention of existing clock_event APIs

struct clock_event_timer's cpumask field gets changed to take pointer,
as does the ->broadcast function.

Another single-patch change.  For safety, we BUG_ON() in
clockevents_register_device() if it's not set.

Signed-off-by: Rusty Russell 
Cc: Ingo Molnar

clockevents: make device shutdown robust

2008-09-16T20:47:02+00:00

The device shut down does not cleanup the next_event variable of the
clock event device. So when the device is reactivated the possible
stale next_event value can prevent the device to be reprogrammed as it
claims to wait on a event already.

This is the root cause of the resurfacing suspend/resume problem,
where systems need key press to come back to life.

Fix this by setting next_event to KTIME_MAX when the device is shut
down. Use a separate function for shutdown which takes care of that
and only keep the direct set mode call in the broadcast code, where we
can not touch the next_event value.

Signed-off-by: Thomas Gleixner

clockevents: prevent clockevent event_handler ending up handler_noop

2008-09-05T09:11:51+00:00

There is a ordering related problem with clockevents code, due to which
clockevents_register_device() called after tickless/highres switch
will not work. The new clockevent ends up with clockevents_handle_noop as
event handler, resulting in no timer activity.

The problematic path seems to be

* old device already has hrtimer_interrupt as the event_handler
* new clockevent device registers with a higher rating
* tick_check_new_device() is called
  * clockevents_exchange_device() gets called
    * old->event_handler is set to clockevents_handle_noop
  * tick_setup_device() is called for the new device
    * which sets new->event_handler using the old->event_handler which is noop.

Change the ordering so that new device inherits the proper handler.

This does not have any issue in normal case as most likely all the clockevent
devices are setup before the highres switch. But, can potentially be affecting
some corner case where HPET force detect happens after the highres switch.
This was a problem with HPET in MSI mode code that we have been experimenting
with.

Signed-off-by: Venkatesh Pallipadi 
Signed-off-by: Shaohua Li 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

time: fix typo in comments

2008-02-08T17:22:29+00:00

Fix typo in comments.

BTW: I have to fix coding style in arch/ia64/kernel/time.c also, otherwise
checkpatch.pl will be complaining.

Signed-off-by: Li Zefan 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: john stultz 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

clockevent: simplify list operations

2008-02-08T17:22:29+00:00

list_for_each_safe() suffices here.

Signed-off-by: Li Zefan 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: john stultz 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

x86: make clockevents more robust

2008-01-30T12:30:03+00:00

detect zero event-device multiplicators - they then cause
division-by-zero crashes if a clockevent has been initialized
incorrectly.

Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

clockevents: warn once when program_event() is called with negative expiry

2007-12-07T18:16:17+00:00

The hrtimer problem with large relative timeouts resulting in a
negative expiry time went unnoticed as there is no check in the
clockevents_program_event() code. Put a check there with a WARN_ONCE
to avoid such problems in the future.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

clockevents: Allow build w/o run-tine usage for migration purposes

2007-10-12T21:04:05+00:00

Migration aid to allow preparatory patches which introduce not yet
used parts of clock events code.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar 
Signed-off-by: Arjan van de Ven

timer: remove clockevents_unregister_notifier

2007-08-11T22:47:42+00:00

I find a function(clockevents_unregister_notifier) which is not called by
anything in tree.

Signed-off-by: Miao Xie 
Acked-by: Thomas Gleixner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds