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linux_old1/include/linux/alarmtimer.h

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timers: Introduce in-kernel alarm-timer interface This provides the in kernel interface and infrastructure for alarm-timers. Alarm-timers are a hybrid style timer, similar to hrtimers, but when the system is suspended, the RTC device is set to fire and wake the system for when the soonest alarm-timer expires. The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 This in-kernel interface should be fairly compatible with the Android alarm driver in-kernel interface, but has the advantage of utilizing the new RTC timerqueue code instead of doing direct RTC manipulation. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-01-12 01:42:13 +08:00
#ifndef _LINUX_ALARMTIMER_H
#define _LINUX_ALARMTIMER_H
#include <linux/time.h>
#include <linux/hrtimer.h>
#include <linux/timerqueue.h>
#include <linux/rtc.h>
enum alarmtimer_type {
ALARM_REALTIME,
ALARM_BOOTTIME,
ALARM_NUMTYPE,
};
alarmtimers: Change alarmtimer functions to return alarmtimer_restart values In order to properly fix the denial of service issue with high freq periodic alarm timers, we need to push the re-arming logic into the alarm timer handler, much as the hrtimer code does. This patch introduces alarmtimer_restart enum and changes the alarmtimer handler declarations to use it as a return value. Further, to ease following changes, it extends the alarmtimer handler functions to also take the time at expiration. No logic is yet modified. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 01:37:59 +08:00
enum alarmtimer_restart {
ALARMTIMER_NORESTART,
ALARMTIMER_RESTART,
};
alarmtimers: Add more refined alarm state tracking In order to allow for functionality like try_to_cancel, add more refined state tracking (similar to hrtimers). CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 03:30:21 +08:00
#define ALARMTIMER_STATE_INACTIVE 0x00
#define ALARMTIMER_STATE_ENQUEUED 0x01
timers: Improve alarmtimer comments and minor fixes This patch addresses a number of minor comment improvements and other minor issues from Thomas' review of the alarmtimers code. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-04-29 03:58:11 +08:00
/**
* struct alarm - Alarm timer structure
* @node: timerqueue node for adding to the event list this value
* also includes the expiration time.
alarmtimer: Fix comments describing structure fields Updated struct alarm and struct alarm_timer descriptions. Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Pratyush Patel <pratyushpatel.1995@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2016-06-14 17:00:42 +08:00
* @timer: hrtimer used to schedule events while running
timers: Improve alarmtimer comments and minor fixes This patch addresses a number of minor comment improvements and other minor issues from Thomas' review of the alarmtimers code. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-04-29 03:58:11 +08:00
* @function: Function pointer to be executed when the timer fires.
alarmtimer: Fix comments describing structure fields Updated struct alarm and struct alarm_timer descriptions. Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Pratyush Patel <pratyushpatel.1995@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2016-06-14 17:00:42 +08:00
* @type: Alarm type (BOOTTIME/REALTIME).
* @state: Flag that represents if the alarm is set to fire or not.
timers: Improve alarmtimer comments and minor fixes This patch addresses a number of minor comment improvements and other minor issues from Thomas' review of the alarmtimers code. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-04-29 03:58:11 +08:00
* @data: Internal data value.
*/
timers: Introduce in-kernel alarm-timer interface This provides the in kernel interface and infrastructure for alarm-timers. Alarm-timers are a hybrid style timer, similar to hrtimers, but when the system is suspended, the RTC device is set to fire and wake the system for when the soonest alarm-timer expires. The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 This in-kernel interface should be fairly compatible with the Android alarm driver in-kernel interface, but has the advantage of utilizing the new RTC timerqueue code instead of doing direct RTC manipulation. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-01-12 01:42:13 +08:00
struct alarm {
struct timerqueue_node node;
alarmtimer: Use hrtimer per-alarm instead of per-base 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 <arve@android.com> Cc: Colin Cross <ccross@android.com> Cc: Thomas Gleixner <tglx@linutronix.de> Reported-by: Arve Hjønnevåg <arve@android.com> Tested-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-09-14 07:12:16 +08:00
struct hrtimer timer;
alarmtimers: Change alarmtimer functions to return alarmtimer_restart values In order to properly fix the denial of service issue with high freq periodic alarm timers, we need to push the re-arming logic into the alarm timer handler, much as the hrtimer code does. This patch introduces alarmtimer_restart enum and changes the alarmtimer handler declarations to use it as a return value. Further, to ease following changes, it extends the alarmtimer handler functions to also take the time at expiration. No logic is yet modified. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 01:37:59 +08:00
enum alarmtimer_restart (*function)(struct alarm *, ktime_t now);
timers: Introduce in-kernel alarm-timer interface This provides the in kernel interface and infrastructure for alarm-timers. Alarm-timers are a hybrid style timer, similar to hrtimers, but when the system is suspended, the RTC device is set to fire and wake the system for when the soonest alarm-timer expires. The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 This in-kernel interface should be fairly compatible with the Android alarm driver in-kernel interface, but has the advantage of utilizing the new RTC timerqueue code instead of doing direct RTC manipulation. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-01-12 01:42:13 +08:00
enum alarmtimer_type type;
alarmtimers: Add more refined alarm state tracking In order to allow for functionality like try_to_cancel, add more refined state tracking (similar to hrtimers). CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 03:30:21 +08:00
int state;
timers: Introduce in-kernel alarm-timer interface This provides the in kernel interface and infrastructure for alarm-timers. Alarm-timers are a hybrid style timer, similar to hrtimers, but when the system is suspended, the RTC device is set to fire and wake the system for when the soonest alarm-timer expires. The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 This in-kernel interface should be fairly compatible with the Android alarm driver in-kernel interface, but has the advantage of utilizing the new RTC timerqueue code instead of doing direct RTC manipulation. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-01-12 01:42:13 +08:00
void *data;
};
void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
alarmtimers: Change alarmtimer functions to return alarmtimer_restart values In order to properly fix the denial of service issue with high freq periodic alarm timers, we need to push the re-arming logic into the alarm timer handler, much as the hrtimer code does. This patch introduces alarmtimer_restart enum and changes the alarmtimer handler declarations to use it as a return value. Further, to ease following changes, it extends the alarmtimer handler functions to also take the time at expiration. No logic is yet modified. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 01:37:59 +08:00
enum alarmtimer_restart (*function)(struct alarm *, ktime_t));
alarmtimer: Get rid of unused return value We want to get rid of the hrtimer_start() return value and the alarm timer return value is nowhere used. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20150414203503.243910615@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-04-15 05:09:18 +08:00
void alarm_start(struct alarm *alarm, ktime_t start);
void alarm_start_relative(struct alarm *alarm, ktime_t start);
alarmtimer: Add functions for timerfd support 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 <toddpoynor@google.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-05-16 05:38:11 +08:00
void alarm_restart(struct alarm *alarm);
alarmtimers: Add try_to_cancel functionality There's a number of edge cases when cancelling a alarm, so to be sure we accurately do so, introduce try_to_cancel, which returns proper failure errors if it cannot. Also modify cancel to spin until the alarm is properly disabled. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 03:41:36 +08:00
int alarm_try_to_cancel(struct alarm *alarm);
int alarm_cancel(struct alarm *alarm);
timers: Introduce in-kernel alarm-timer interface This provides the in kernel interface and infrastructure for alarm-timers. Alarm-timers are a hybrid style timer, similar to hrtimers, but when the system is suspended, the RTC device is set to fire and wake the system for when the soonest alarm-timer expires. The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 This in-kernel interface should be fairly compatible with the Android alarm driver in-kernel interface, but has the advantage of utilizing the new RTC timerqueue code instead of doing direct RTC manipulation. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-01-12 01:42:13 +08:00
alarmtimers: Add alarm_forward functionality In order to avoid wasting time expiring and re-adding very high freq periodic alarmtimers, introduce alarm_forward() which is similar to hrtimer_forward and moves the timer to the next future expiration time and returns the number of overruns. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 02:31:03 +08:00
u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);
alarmtimer: Add functions for timerfd support 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 <toddpoynor@google.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-05-16 05:38:11 +08:00
u64 alarm_forward_now(struct alarm *alarm, ktime_t interval);
ktime_t alarm_expires_remaining(const struct alarm *alarm);
alarmtimers: Add alarm_forward functionality In order to avoid wasting time expiring and re-adding very high freq periodic alarmtimers, introduce alarm_forward() which is similar to hrtimer_forward and moves the timer to the next future expiration time and returns the number of overruns. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-11 02:31:03 +08:00
alarmtimer: Provide accessor to alarmtimer rtc device The Android alarm interface provides a settime call that sets both the alarmtimer RTC device and CLOCK_REALTIME to the same value. Since there may be multiple rtc devices, provide a hook to access the one the alarmtimer infrastructure is using. CC: Colin Cross <ccross@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Android Kernel Team <kernel-team@android.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-21 03:31:45 +08:00
/* Provide way to access the rtc device being used by alarmtimers */
struct rtc_device *alarmtimer_get_rtcdev(void);
timers: Introduce in-kernel alarm-timer interface This provides the in kernel interface and infrastructure for alarm-timers. Alarm-timers are a hybrid style timer, similar to hrtimers, but when the system is suspended, the RTC device is set to fire and wake the system for when the soonest alarm-timer expires. The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 This in-kernel interface should be fairly compatible with the Android alarm driver in-kernel interface, but has the advantage of utilizing the new RTC timerqueue code instead of doing direct RTC manipulation. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-01-12 01:42:13 +08:00
#endif