user/sven/linux.git/kernel/time/alarmtimer.c, branch v3.14.33

alarmtimer: Lock k_itimer during timer callback

2014-10-05T21:52:22Z

commit 474e941bed9262f5fa2394f9a4a67e24499e5926 upstream. Locks the k_itimer's it_lock member when handling the alarm timer's expiry callback. The regular posix timers defined in posix-timers.c have this lock held during timout processing because their callbacks are routed through posix_timer_fn(). The alarm timers follow a different path, so they ought to grab the lock somewhere else. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Richard Cochran Cc: Prarit Bhargava Cc: Sharvil Nanavati Signed-off-by: Richard Larocque Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman

alarmtimer: Do not signal SIGEV_NONE timers

2014-10-05T21:52:22Z

commit 265b81d23a46c39df0a735a3af4238954b41a4c2 upstream. Avoids sending a signal to alarm timers created with sigev_notify set to SIGEV_NONE by checking for that special case in the timeout callback. The regular posix timers avoid sending signals to SIGEV_NONE timers by not scheduling any callbacks for them in the first place. Although it would be possible to do something similar for alarm timers, it's simpler to handle this as a special case in the timeout. Prior to this patch, the alarm timer would ignore the sigev_notify value and try to deliver signals to the process anyway. Even worse, the sanity check for the value of sigev_signo is skipped when SIGEV_NONE was specified, so the signal number could be bogus. If sigev_signo was an unitialized value (as it often would be if SIGEV_NONE is used), then it's hard to predict which signal will be sent. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Richard Cochran Cc: Prarit Bhargava Cc: Sharvil Nanavati Signed-off-by: Richard Larocque Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman

alarmtimer: Return relative times in timer_gettime

2014-10-05T21:52:21Z

commit e86fea764991e00a03ff1e56409ec9cacdbda4c9 upstream. Returns the time remaining for an alarm timer, rather than the time at which it is scheduled to expire. If the timer has already expired or it is not currently scheduled, the it_value's members are set to zero. This new behavior matches that of the other posix-timers and the POSIX specifications. This is a change in user-visible behavior, and may break existing applications. Hopefully, few users rely on the old incorrect behavior. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Richard Cochran Cc: Prarit Bhargava Cc: Sharvil Nanavati Signed-off-by: Richard Larocque [jstultz: minor style tweak] Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman

alarmtimer: Fix bug where relative alarm timers were treated as absolute

2014-07-28T15:06:03Z

commit 16927776ae757d0d132bdbfabbfe2c498342bd59 upstream. Sharvil noticed with the posix timer_settime interface, using the CLOCK_REALTIME_ALARM or CLOCK_BOOTTIME_ALARM clockid, if the users tried to specify a relative time timer, it would incorrectly be treated as absolute regardless of the state of the flags argument. This patch corrects this, properly checking the absolute/relative flag, as well as adds further error checking that no invalid flag bits are set. Reported-by: Sharvil Nanavati Signed-off-by: John Stultz Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Prarit Bhargava Cc: Sharvil Nanavati Link: http://lkml.kernel.org/r/1404767171-6902-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

alarmtimer: return EINVAL instead of ENOTSUPP if rtcdev doesn't exist

2013-10-18T23:23:58Z

Fedora Ruby maintainer reported latest Ruby doesn't work on Fedora Rawhide on ARM. (http://bugs.ruby-lang.org/issues/9008) Because of, commit 1c6b39ad3f (alarmtimers: Return -ENOTSUPP if no RTC device is present) intruduced to return ENOTSUPP when clock_get{time,res} can't find a RTC device. However this is incorrect. First, ENOTSUPP isn't exported to userland (ENOTSUP or EOPNOTSUP are the closest userland equivlents). Second, Posix and Linux man pages agree that clock_gettime and clock_getres should return EINVAL if clk_id argument is invalid. While the arugment that the clockid is valid, but just not supported on this hardware could be made, this is just a technicality that doesn't help userspace applicaitons, and only complicates error handling. Thus, this patch changes the code to use EINVAL. Cc: Thomas Gleixner Cc: Frederic Weisbecker Cc: stable #3.0 and up Reported-by: Vit Ondruch Signed-off-by: KOSAKI Motohiro [jstultz: Tweaks to commit message to include full rational] Signed-off-by: John Stultz

alarmtimer: Export symbols of functions declared in linux/alarmtimer.h

2013-06-12T21:02:12Z

Export symbols so they can be used by drivers/staging/android/alarm-dev.c if it is built as a module. So far alarm-dev is built-in but module support is planned (see drivers/staging/android/TODO). Signed-off-by: Marcus Gelderie [jstultz: tweaked commit message, also export newly added functions] Signed-off-by: John Stultz

alarmtimer: Add functions for timerfd support

2013-05-29T19:57:34Z

Add functions needed for hooking up alarmtimer to timerfd: * alarm_restart: Similar to hrtimer_restart, restart an alarmtimer after the expires time has already been updated (as with alarm_forward). * alarm_forward_now: Similar to hrtimer_forward_now, move the expires time forward to an interval from the current time of the associated clock. * alarm_start_relative: Start an alarmtimer with an expires time relative to the current time of the associated clock. * alarm_expires_remaining: Similar to hrtimer_expires_remaining, return the amount of time remaining until alarm expiry. Signed-off-by: Todd Poynor Signed-off-by: John Stultz

alarmtimer: Rename alarmtimer_remove to alarmtimer_dequeue

2012-09-24T16:38:03Z

Now that alarmtimer_remove has been simplified, change its name to _dequeue to better match its paired _enqueue function. Cc: Arve Hjønnevåg Cc: Colin Cross Cc: Thomas Gleixner Signed-off-by: John Stultz

alarmtimer: Use hrtimer per-alarm instead of per-base

2012-09-24T16:38:02Z

Arve Hjønnevåg reported numerous crashes from the "BUG_ON(timer->state != HRTIMER_STATE_CALLBACK)" check in __run_hrtimer after it called alarmtimer_fired. It ends up the alarmtimer code was not properly handling possible failures of hrtimer_try_to_cancel, and because these faulres occur when the underlying base hrtimer is being run, this limits the ability to properly handle modifications to any alarmtimers on that base. Because much of the logic duplicates the hrtimer logic, it seems that we might as well have a per-alarmtimer hrtimer, and avoid the extra complextity of trying to multiplex many alarmtimers off of one hrtimer. Thus this patch moves the hrtimer to the alarm structure and simplifies the management logic. Changelog: v2: * Includes a fix for double alarm_start calls found by Arve Cc: Arve Hjønnevåg Cc: Colin Cross Cc: Thomas Gleixner Reported-by: Arve Hjønnevåg Tested-by: Arve Hjønnevåg Signed-off-by: John Stultz

alarmtimer: Implement minimum alarm interval for allowing suspend

2012-09-24T16:38:01Z

alarmtimer suspend return -EBUSY if the next alarm will fire in less than 2 seconds. This allows one RTC seconds tick to occur subsequent to this check before the alarm wakeup time is set, ensuring the wakeup time is still in the future (assuming the RTC does not tick one more second prior to setting the alarm). If suspend is rejected due to an imminent alarm, hold a wakeup source for 2 seconds to process the alarm prior to reattempting suspend. If setting the alarm incurs an -ETIME for an alarm set in the past, or any other problem setting the alarm, abort suspend and hold a wakelock for 1 second while the alarm is allowed to be serviced or other hopefully transient conditions preventing the alarm clear up. Signed-off-by: Todd Poynor Signed-off-by: John Stultz