Revert "Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm"

This reverts commit 76502d502797af971c6e560fcea4579024880e3f.

SOD again after call, not wantto use any 3.6 heavy changes!
More to be restored!
Revert "+ cacheflush: return error to userspace when flushing syscall fails -> https://github.com/torvalds/linux/commit/c5102f5935503ebebad46e137d0eef68f272cc16"

This reverts commit f61fdf58c76fe37199f5e9e512ddb064a7cfd0a7.

Our Build not ready for 3.6.y cache changes!
PM / Sleep: Initialize wakeup source locks in wakeup_source_add()

Initialize wakeup source locks in wakeup_source_add() instead of
wakeup_source_create(), because otherwise the locks of the wakeup
sources that haven't been allocated with wakeup_source_create()
aren't initialized and handled properly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
PM / Sleep: Fix possible infinite loop during wakeup source destruction

If wakeup_source_destroy() is called for an active wakeup source that
is never deactivated, it will spin forever.  To prevent that from
happening, make wakeup_source_destroy() call __pm_relax() for the
wakeup source object it is about to free instead of waiting until
it will be deactivated by someone else.  However, for this to work
it also needs to make sure that the timer function will not be
executed after the final __pm_relax(), so make it run
del_timer_sync() on the wakeup source's timer beforehand.

Additionally, update the kerneldoc comment to document the
requirement that __pm_stay_awake() and __pm_wakeup_event() must not
be run in parallel with wakeup_source_destroy().

Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
PM / Sleep: Fix race conditions related to wakeup source timer function

If __pm_wakeup_event() has been used (with a nonzero timeout) to
report a wakeup event and then __pm_relax() immediately followed by
__pm_stay_awake() is called or __pm_wakeup_event() is called once
again for the same wakeup source object before its timer expires, the
timer function pm_wakeup_timer_fn() may still be run as a result of
the previous __pm_wakeup_event() call.  In either of those cases it
may mistakenly deactivate the wakeup source that has just been
activated.

To prevent that from happening, make wakeup_source_deactivate()
clear the wakeup source's timer_expires field and make
pm_wakeup_timer_fn() check if timer_expires is different from zero
and if it's not in future before calling wakeup_source_deactivate()
(if timer_expires is 0, it means that the timer has just been
deleted and if timer_expires is in future, it means that the timer
has just been rescheduled to a different time).

Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
PM / Sleep: Make __pm_stay_awake() delete wakeup source timers

If __pm_stay_awake() is called after __pm_wakeup_event() for the same
wakep source object before its timer expires, it won't cancel the
timer, so the wakeup source will be deactivated from the timer
function as scheduled by __pm_wakeup_event().  In that case
__pm_stay_awake() doesn't have any effect beyond incrementing
the wakeup source's event_count field, although it should cancel
the timer and make the wakeup source stay active until __pm_relax()
is called for it.

To fix this problem make __pm_stay_awake() delete the wakeup source's
timer and ensure that it won't be deactivated from the timer funtion
afterwards by clearing its timer_expires field.

Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
PM / Sleep: Add more wakeup source initialization routines

The existing wakeup source initialization routines are not
particularly useful for wakeup sources that aren't created by
wakeup_source_create(), because their users have to open code
filling the objects with zeros and setting their names.  For this
reason, introduce routines that can be used for initializing, for
example, static wakeup source objects.

Requested-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
PM / Sleep: Use wait queue to signal "no wakeup events in progress"

The current wakeup source deactivation code doesn't do anything when
the counter of wakeup events in progress goes down to zero, which
requires pm_get_wakeup_count() to poll that counter periodically.
Although this reduces the average time it takes to deactivate a
wakeup source, it also may lead to a substantial amount of unnecessary
polling if there are extended periods of wakeup activity.  Thus it
seems reasonable to use a wait queue for signaling the "no wakeup
events in progress" condition and remove the polling.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: mark gross <markgross@thegnar.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PM / Sleep: Change wakeup source statistics to follow Android

Wakeup statistics used by Android are slightly different from what we
have in wakeup sources at the moment and there aren't any known
users of those statistics other than Android, so modify them to make
it easier for Android to switch to wakeup sources.

This removes the struct wakeup_source's hit_cout field, which is very
rough and therefore not very useful, and adds two new fields,
wakeup_count and expire_count.  The first one tracks how many times
the wakeup source is activated with events_check_enabled set (which
roughly corresponds to the situations when a system power transition
to a sleep state is in progress and would be aborted by this wakeup
source if it were the only active one at that time) and the second
one is the number of times the wakeup source has been activated with
a timeout that expired.

Additionally, the last_time field is now updated when the wakeup
source is deactivated too (previously it was only updated during
the wakeup source's activation), which seems to be what Android does
with the analogous counter for wakelocks.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints

Add tracepoints to wakeup_source_activate and wakeup_source_deactivate.
Useful for checking that specific wakeup sources overlap as expected.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
kk