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2011-05-20clockevents/source: Use u64 to make 32bit happyThomas Gleixner2-2/+2
unsigned long is not 64bit on 32bit machine. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-20Merge branch 'timers-core-for-linus' of ↵Linus Torvalds3-4/+748
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimer: Make lookup table const RTC: Disable CONFIG_RTC_CLASS from being built as a module timers: Fix alarmtimer build issues when CONFIG_RTC_CLASS=n timers: Remove delayed irqwork from alarmtimers implementation timers: Improve alarmtimer comments and minor fixes timers: Posix interface for alarm-timers timers: Introduce in-kernel alarm-timer interface timers: Add rb_init_node() to allow for stack allocated rb nodes time: Add timekeeping_inject_sleeptime
2011-05-20Merge branch 'timers-clockevents-for-linus' of ↵Linus Torvalds2-19/+83
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-clockevents-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: hpet: Cleanup the clockevents init and register code x86: Convert PIT to clockevents_config_and_register() clockevents: Provide interface to reconfigure an active clock event device clockevents: Provide combined configure and register function clockevents: Restructure clock_event_device members clocksource: Get rid of the hardcoded 5 seconds sleep time limit clocksource: Restructure clocksource struct members
2011-05-19clockevents: Provide interface to reconfigure an active clock event deviceThomas Gleixner1-0/+20
Some ARM SoCs have clock event devices which have their frequency modified due to frequency scaling. Provide an interface which allows to reconfigure an active device. After reconfiguration reprogram the current pending event. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: LAK <linux-arm-kernel@lists.infradead.org> Cc: John Stultz <john.stultz@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Link: http://lkml.kernel.org/r/%3C20110518210136.437459958%40linutronix.de%3E
2011-05-19clockevents: Provide combined configure and register functionThomas Gleixner1-0/+44
All clockevent devices have the same open coded initialization functions. Provide an interface which does all necessary initialization in the core code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Link: http://lkml.kernel.org/r/%3C20110518210136.331975870%40linutronix.de%3E
2011-05-19clocksource: Get rid of the hardcoded 5 seconds sleep time limitThomas Gleixner1-19/+19
Slow clocksources can have a way longer sleep time than 5 seconds and even fast ones can easily cope with 600 seconds and still maintain proper accuracy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Link: http://lkml.kernel.org/r/%3C20110518210136.109811585%40linutronix.de%3E
2011-05-17tick: Clear broadcast active bit when switching to oneshotThomas Gleixner1-1/+11
The first cpu which switches from periodic to oneshot mode switches also the broadcast device into oneshot mode. The broadcast device serves as a backup for per cpu timers which stop in deeper C-states. To avoid starvation of the cpus which might be in idle and depend on broadcast mode it marks the other cpus as broadcast active and sets the brodcast expiry value of those cpus to the next tick. The oneshot mode broadcast bit for the other cpus is sticky and gets only cleared when those cpus exit idle. If a cpu was not idle while the bit got set in consequence the bit prevents that the broadcast device is armed on behalf of that cpu when it enters idle for the first time after it switched to oneshot mode. In most cases that goes unnoticed as one of the other cpus has usually a timer pending which keeps the broadcast device armed with a short timeout. Now if the only cpu which has a short timer active has the bit set then the broadcast device will not be armed on behalf of that cpu and will fire way after the expected timer expiry. In the case of Christians bug report it took ~145 seconds which is about half of the wrap around time of HPET (the limit for that device) due to the fact that all other cpus had no timers armed which expired before the 145 seconds timeframe. The solution is simply to clear the broadcast active bit unconditionally when a cpu switches to oneshot mode after the first cpu switched the broadcast device over. It's not idle at that point otherwise it would not be executing that code. [ I fundamentally hate that broadcast crap. Why the heck thought some folks that when going into deep idle it's a brilliant concept to switch off the last device which brings the cpu back from that state? ] Thanks to Christian for providing all the valuable debug information! Reported-and-tested-by: Christian Hoffmann <email@christianhoffmann.info> Cc: John Stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/%3Calpine.LFD.2.02.1105161105170.3078%40ionos%3E Cc: stable@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-05clocksource: Install completely before selectingjohn stultz1-2/+2
Christian Hoffmann reported that the command line clocksource override with acpi_pm timer fails: Kernel command line: <SNIP> clocksource=acpi_pm hpet clockevent registered Switching to clocksource hpet Override clocksource acpi_pm is not HRT compatible. Cannot switch while in HRT/NOHZ mode. The watchdog code is what enables CLOCK_SOURCE_VALID_FOR_HRES, but we actually end up selecting the clocksource before we enqueue it into the watchdog list, so that's why we see the warning and fail to switch to acpi_pm timer as requested. That's particularly bad when we want to debug timekeeping related problems in early boot. Put the selection call last. Reported-by: Christian Hoffmann <email@christianhoffmann.info> Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: stable@kernel.org # 32... Link: http://lkml.kernel.org/r/%3C1304558210.2943.24.camel%40work-vm%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-02timers: Fix alarmtimer build issues when CONFIG_RTC_CLASS=nJohn Stultz1-2/+18
Ingo pointed out that the alarmtimers won't build if CONFIG_RTC_CLASS=n. This patch adds proper ifdefs to the alarmtimer code to disable the rtc usage if it is not built in. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-04-29timers: Remove delayed irqwork from alarmtimers implementationJohn Stultz1-23/+9
Thomas asked about the delayed irq work in the alarmtimers code, and I realized that it was a legacy from when the alarmtimer base lock was a mutex (due to concerns that we'd be interacting with the RTC device, which is protected by mutexes). Since the alarmtimer base is now protected by a spinlock, we can simply execute alarmtimer functions directly from the hrtimer callback. Should any future alarmtimer functions sleep, they can simply manage scheduling any delayed work themselves. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-04-29timers: Improve alarmtimer comments and minor fixesJohn Stultz1-40/+27
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>
2011-04-27timers: Posix interface for alarm-timersJohn Stultz1-0/+330
This patch exposes alarm-timers to userland via the posix clock and timers interface, using two new clockids: CLOCK_REALTIME_ALARM and CLOCK_BOOTTIME_ALARM. Both clockids behave identically to CLOCK_REALTIME and CLOCK_BOOTTIME, respectively, but timers set against the _ALARM suffixed clockids will wake the system if it is suspended. Some background can be found here: https://lwn.net/Articles/429925/ 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 While the in-kernel interface is pretty similar between alarm-timers and Android alarm driver, the user-space interface for the Android alarm driver is via ioctls to a new char device. As mentioned above, I've instead chosen to export this functionality via the posix interface, as it seemed a little simpler and avoids creating duplicate interfaces to things like CLOCK_REALTIME and CLOCK_MONOTONIC under alternate names (ie:ANDROID_ALARM_RTC and ANDROID_ALARM_SYSTEMTIME). The semantics of the Android alarm driver are different from what this posix interface provides. For instance, threads other then the thread waiting on the Android alarm driver are able to modify the alarm being waited on. Also this interface does not allow the same wakelock semantics that the Android driver provides (ie: kernel takes a wakelock on RTC alarm-interupt, and holds it through process wakeup, and while the process runs, until the process either closes the char device or calls back in to wait on a new alarm). One potential way to implement similar semantics may be via the timerfd infrastructure, but this needs more research. There may also need to be some sort of sysfs system level policy hooks that allow alarm timers to be disabled to keep them from firing at inappropriate times (ie: laptop in a well insulated bag, mid-flight). 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>
2011-04-27timers: Introduce in-kernel alarm-timer interfaceJohn Stultz2-1/+376
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>
2011-04-27time: Add timekeeping_inject_sleeptimeJohn Stultz1-3/+53
Some platforms cannot implement read_persistent_clock, as their RTC devices are only accessible when interrupts are enabled. This keeps them from being used by the timekeeping code on resume to measure the time in suspend. The RTC layer tries to work around this, by calling do_settimeofday on resume after irqs are reenabled to set the time properly. However, this only corrects CLOCK_REALTIME, and does not properly adjust the sleep time value. This causes btime in /proc/stat to be incorrect as well as making the new CLOCK_BOTTTIME inaccurate. This patch resolves the issue by introducing a new timekeeping hook to allow the RTC layer to inject the sleep time on resume. The code also checks to make sure that read_persistent_clock is nonfunctional before setting the sleep time, so that should the RTC's HCTOSYS option be configured in on a system that does support read_persistent_clock we will not increase the total_sleep_time twice. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-04-18posix clocks: Replace mutex with reader/writer semaphoreRichard Cochran1-15/+9
A dynamic posix clock is protected from asynchronous removal by a mutex. However, using a mutex has the unwanted effect that a long running clock operation in one process will unnecessarily block other processes. For example, one process might call read() to get an external time stamp coming in at one pulse per second. A second process calling clock_gettime would have to wait for almost a whole second. This patch fixes the issue by using a reader/writer semaphore instead of a mutex. Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/%3C20110330132421.GA31771%40riccoc20.at.omicron.at%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-04-07Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6Linus Torvalds2-2/+2
* 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6: Fix common misspellings
2011-04-04ntp: fix non privileged system time shiftingRichard Cochran1-0/+2
The ADJ_SETOFFSET bit added in commit 094aa188 ("ntp: Add ADJ_SETOFFSET mode bit") also introduced a way for any user to change the system time. Sneaky or buggy calls to adjtimex() could set ADJ_OFFSET_SS_READ | ADJ_SETOFFSET which would result in a successful call to timekeeping_inject_offset(). This patch fixes the issue by adding the capability check. Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-31Fix common misspellingsLucas De Marchi2-2/+2
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-24timekeeping: Use syscore_ops instead of sysdev class and sysdevRafael J. Wysocki1-19/+8
The timekeeping subsystem uses a sysdev class and a sysdev for executing timekeeping_suspend() after interrupts have been turned off on the boot CPU (during system suspend) and for executing timekeeping_resume() before turning on interrupts on the boot CPU (during system resume). However, since both of these functions ignore their arguments, the entire mechanism may be replaced with a struct syscore_ops object which is simpler. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-16Merge branch 'timers-core-for-linus' of ↵Linus Torvalds11-14/+628
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (62 commits) posix-clocks: Check write permissions in posix syscalls hrtimer: Remove empty hrtimer_init_hres_timer() hrtimer: Update hrtimer->state documentation hrtimer: Update base[CLOCK_BOOTTIME].offset correctly timers: Export CLOCK_BOOTTIME via the posix timers interface timers: Add CLOCK_BOOTTIME hrtimer base time: Extend get_xtime_and_monotonic_offset() to also return sleep time: Introduce get_monotonic_boottime and ktime_get_boottime hrtimers: extend hrtimer base code to handle more then 2 clockids ntp: Remove redundant and incorrect parameter check mn10300: Switch do_timer() to xtimer_update() posix clocks: Introduce dynamic clocks posix-timers: Cleanup namespace posix-timers: Add support for fd based clocks x86: Add clock_adjtime for x86 posix-timers: Introduce a syscall for clock tuning. time: Splitout compat timex accessors ntp: Add ADJ_SETOFFSET mode bit time: Introduce timekeeping_inject_offset posix-timer: Update comment ... Fix up new system-call-related conflicts in arch/x86/ia32/ia32entry.S arch/x86/include/asm/unistd_32.h arch/x86/include/asm/unistd_64.h arch/x86/kernel/syscall_table_32.S (name_to_handle_at()/open_by_handle_at() vs clock_adjtime()), and some due to movement of get_jiffies_64() in: kernel/time.c
2011-03-12posix-clocks: Check write permissions in posix syscallsTorben Hohn1-2/+12
pc_clock_settime() and pc_clock_adjtime() do not check whether the fd was opened in write mode, so a clock can be set with a read only fd. [ tglx: We deliberately do not return -EPERM as we want this to be distingushable from the capability based permission check ] Signed-off-by: Torben Hohn <torbenh@gmx.de> LKML-Reference: <1299173174-348-4-git-send-email-torbenh@gmx.de> Cc: Richard Cochran <richard.cochran@omicron.at> Cc: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de>
2011-02-26clockevents: Prevent oneshot mode when broadcast device is periodicThomas Gleixner3-1/+18
When the per cpu timer is marked CLOCK_EVT_FEAT_C3STOP, then we only can switch into oneshot mode, when the backup broadcast device supports oneshot mode as well. Otherwise we would try to switch the broadcast device into an unsupported mode unconditionally. This went unnoticed so far as the current available broadcast devices support oneshot mode. Seth unearthed this problem while debugging and working around an hpet related BIOS wreckage. Add the necessary check to tick_is_oneshot_available(). Reported-and-tested-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <alpine.LFD.2.00.1102252231200.2701@localhost6.localdomain6> Cc: stable@kernel.org # .21 ->
2011-02-21time: Extend get_xtime_and_monotonic_offset() to also return sleepJohn Stultz1-2/+6
Extend get_xtime_and_monotonic_offset to get_xtime_and_monotonic_and_sleep_offset(). CC: Jamie Lokier <jamie@shareable.org> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alexander Shishkin <virtuoso@slind.org> CC: Arve Hjønnevåg <arve@android.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-02-21time: Introduce get_monotonic_boottime and ktime_get_boottimeJohn Stultz1-1/+50
This adds new functions that return the monotonic time since boot (in other words, CLOCK_MONOTONIC + suspend time). CC: Jamie Lokier <jamie@shareable.org> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alexander Shishkin <virtuoso@slind.org> CC: Arve Hjønnevåg <arve@android.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-02-18ntp: Remove redundant and incorrect parameter checkRichard Cochran1-3/+3
The ADJ_SETOFFSET code redundantly checks the range of the nanoseconds field of the time value. This field is checked again in the subsequent call to timekeeping_inject_offset(). Also, as is, the check will not detect whether the number of microseconds is out of range. Let timekeeping_inject_offset() do the error checking. Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Cc: johnstul@us.ibm.com LKML-Reference: <20110218090724.GA2924@riccoc20.at.omicron.at> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-12timer debug: Hide kernel addresses via %pK in /proc/timer_listKees Cook1-2/+2
In the continuing effort to avoid kernel addresses leaking to unprivileged users, this patch switches to %pK for /proc/timer_list reporting. Signed-off-by: Kees Cook <kees.cook@canonical.com> Cc: John Stultz <johnstul@us.ibm.com> Cc: Dan Rosenberg <drosenberg@vsecurity.com> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <20110212032125.GA23571@outflux.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-02posix clocks: Introduce dynamic clocksRichard Cochran2-1/+443
This patch adds support for adding and removing posix clocks. The clock lifetime cycle is patterned after usb devices. Each clock is represented by a standard character device. In addition, the driver may optionally implement custom character device operations. The posix clock and timer system calls listed below now work with dynamic posix clocks, as well as the traditional static clocks. The following system calls are affected: - clock_adjtime (brand new syscall) - clock_gettime - clock_getres - clock_settime - timer_create - timer_delete - timer_gettime - timer_settime [ tglx: Adapted to the posix-timer cleanup. Moved clock_posix_dynamic to posix-clock.c and made all referenced functions static ] Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Acked-by: John Stultz <johnstul@us.ibm.com> LKML-Reference: <20110201134420.164172635@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-02ntp: Add ADJ_SETOFFSET mode bitRichard Cochran1-0/+11
This patch adds a new mode bit into the timex structure. When set, the bit instructs the kernel to add the given time value to the current time. Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Acked-by: John Stultz <johnstul@us.ibm.com> LKML-Reference: <20110201134320.688829863@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-02time: Introduce timekeeping_inject_offsetJohn Stultz1-0/+36
This adds a kernel-internal timekeeping interface to add or subtract a fixed amount from CLOCK_REALTIME. This makes it so kernel users or interfaces trying to do so do not have to read the time, then add an offset and then call settimeofday(), which adds some extra error in comparision to just simply adding the offset in the kernel timekeeping core. Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Richard Cochran <richard.cochran@omicron.at> LKML-Reference: <20110201134419.584311693@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-02time: Correct the *settime* parametersRichard Cochran1-1/+1
Both settimeofday() and clock_settime() promise with a 'const' attribute not to alter the arguments passed in. This patch adds the missing 'const' attribute into the various kernel functions implementing these calls. Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Acked-by: John Stultz <johnstul@us.ibm.com> LKML-Reference: <20110201134417.545698637@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-01time: Fix legacy arch falloutThomas Gleixner1-0/+4
The xtime/dotimer cleanup broke architectures which do not implement clockevents. Time to send out another __do_IRQ threat. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reported-by: Ingo Molnar <mingo@elte.hu> Cc: Torben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145905.23248.30458.stgit@localhost> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-31time: Make do_timer() and xtime_lock local to kernel/time/Torben Hohn8-5/+9
All callers of do_timer() are converted to xtime_update(). The only users of xtime_lock are in kernel/time/. Make both local to kernel/time/ and remove them from the global header files. [ tglx: Reuse tick-internal.h instead of creating another local header file. Massaged changelog ] Signed-off-by: Torben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-31time: Provide xtime_update()Torben Hohn1-0/+13
xtime_update() takes xtime_lock write locked and calls do_timer(). Provided to replace the do_timer() calls in the architecture code. Signed-off-by: Torben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145910.23248.21379.stgit@localhost> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-31time: Remove unused __get_wall_to_monotonic()Thomas Gleixner1-5/+0
No users left. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-31time: Provide get_xtime_and_monotonic_offset()Torben Hohn1-0/+16
The hrtimer code accesses timekeeping variables under xtime_lock. Provide a sensible accessor function and use it. [ tglx: Removed the conditionals, unused variable, fixed codingstyle and massaged changelog ] Signed-off-by: Torben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145905.23248.30458.stgit@localhost> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-31time: Move get_jiffies_64 to kernel/time/jiffies.cTorben Hohn1-0/+18
Move the jiffies access functions to the jiffies clocksource code. [ tglx: Add missing include ] Signed-off-by: Torben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145900.23248.73352.stgit@localhost> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-31time: Move do_timer() to kernel/time/timekeeping.cTorben Hohn1-1/+13
do_timer() is primary timekeeping related. calc_global_load() is called from do_timer() as well, but that's more for historical reasons. [ tglx: Fixed up the calc_global_load() reject andmassaged changelog ] Signed-off-by: Torben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145855.23248.56933.stgit@localhost> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-19hrtimers: Notify hrtimer users of switches to NOHZ modeStephen Boyd1-3/+4
When NOHZ=y and high res timers are disabled (via cmdline or Kconfig) tick_nohz_switch_to_nohz() will notify the user about switching into NOHZ mode. Nothing is printed for the case where HIGH_RES_TIMERS=y. Fix this for the HIGH_RES_TIMERS=y case by duplicating the printk from the low res NOHZ path in the high res NOHZ path. This confused me since I was thinking 'dmesg | grep -i NOHZ' would tell me if NOHZ was enabled, but if I have hrtimers there is nothing. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1295419594-13085-1-git-send-email-sboyd@codeaurora.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-15Merge branches 'core-fixes-for-linus', 'x86-fixes-for-linus', ↵Linus Torvalds2-6/+6
'timers-fixes-for-linus' and 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rcu: avoid pointless blocked-task warnings rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status rtmutex: Fix comment about why new_owner can be NULL in wake_futex_pi() * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, olpc: Add missing Kconfig dependencies x86, mrst: Set correct APB timer IRQ affinity for secondary cpu x86: tsc: Fix calibration refinement conditionals to avoid divide by zero x86, ia64, acpi: Clean up x86-ism in drivers/acpi/numa.c * 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: timekeeping: Make local variables static time: Rename misnamed minsec argument of clocks_calc_mult_shift() * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Remove syscall_exit_fields tracing: Only process module tracepoints once perf record: Add "nodelay" mode, disabled by default perf sched: Fix list of events, dropping unsupported ':r' modifier Revert "perf tools: Emit clearer message for sys_perf_event_open ENOENT return" perf top: Fix annotate segv perf evsel: Fix order of event list deletion
2011-01-13Merge branch 'for-next' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits) Documentation/trace/events.txt: Remove obsolete sched_signal_send. writeback: fix global_dirty_limits comment runtime -> real-time ppc: fix comment typo singal -> signal drivers: fix comment typo diable -> disable. m68k: fix comment typo diable -> disable. wireless: comment typo fix diable -> disable. media: comment typo fix diable -> disable. remove doc for obsolete dynamic-printk kernel-parameter remove extraneous 'is' from Documentation/iostats.txt Fix spelling milisec -> ms in snd_ps3 module parameter description Fix spelling mistakes in comments Revert conflicting V4L changes i7core_edac: fix typos in comments mm/rmap.c: fix comment sound, ca0106: Fix assignment to 'channel'. hrtimer: fix a typo in comment init/Kconfig: fix typo anon_inodes: fix wrong function name in comment fix comment typos concerning "consistent" poll: fix a typo in comment ... Fix up trivial conflicts in: - drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c) - fs/ext4/ext4.h Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
2011-01-13pps: capture MONOTONIC_RAW timestamps as wellAlexander Gordeev1-0/+43
MONOTONIC_RAW clock timestamps are ideally suited for frequency calculation and also fit well into the original NTP hardpps design. Now phase and frequency can be adjusted separately: the former based on REALTIME clock and the latter based on MONOTONIC_RAW clock. A new function getnstime_raw_and_real is added to timekeeping subsystem to capture both timestamps at the same time and atomically. Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13ntp: add hardpps implementationAlexander Gordeev1-15/+410
This commit adds hardpps() implementation based upon the original one from the NTPv4 reference kernel code from David Mills. However, it is highly optimized towards very fast syncronization and maximum stickness to PPS signal. The typical error is less then a microsecond. To make it sync faster I had to throw away exponential phase filter so that the full phase offset is corrected immediately. Then I also had to throw away median phase filter because it gives a bigger error itself if used without exponential filter. Maybe we will find an appropriate filtering scheme in the future but it's not necessary if the signal quality is ok. Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-12timekeeping: Make local variables staticH Hartley Sweeten1-2/+2
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: John Stultz <johnstul@us.ibm.com> LKML-Reference: <0D753D10438DA54287A00B027084269764CE0E54B7@AUSP01VMBX24.collaborationhost.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-12time: Rename misnamed minsec argument of clocks_calc_mult_shift()Nicolas Pitre1-4/+4
The minsec argument to clocks_calc_mult_shift() is misnamed. It is used to clamp the magnitude of the mult factor so that a multiplication with any value in the given range won't overflow a 64 bit result. Let's rename it to match the actual usage. Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org> Acked-by: John Stultz <johnstul@us.ibm.com> LKML-Reference: <alpine.LFD.2.00.1101111207140.17086@xanadu.home> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-08Merge branch 'for-2.6.38' of ↵Linus Torvalds2-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (30 commits) gameport: use this_cpu_read instead of lookup x86: udelay: Use this_cpu_read to avoid address calculation x86: Use this_cpu_inc_return for nmi counter x86: Replace uses of current_cpu_data with this_cpu ops x86: Use this_cpu_ops to optimize code vmstat: User per cpu atomics to avoid interrupt disable / enable irq_work: Use per cpu atomics instead of regular atomics cpuops: Use cmpxchg for xchg to avoid lock semantics x86: this_cpu_cmpxchg and this_cpu_xchg operations percpu: Generic this_cpu_cmpxchg() and this_cpu_xchg support percpu,x86: relocate this_cpu_add_return() and friends connector: Use this_cpu operations xen: Use this_cpu_inc_return taskstats: Use this_cpu_ops random: Use this_cpu_inc_return fs: Use this_cpu_inc_return in buffer.c highmem: Use this_cpu_xx_return() operations vmstat: Use this_cpu_inc_return for vm statistics x86: Support for this_cpu_add, sub, dec, inc_return percpu: Generic support for this_cpu_add, sub, dec, inc_return ... Fixed up conflicts: in arch/x86/kernel/{apic/nmi.c, apic/x2apic_uv_x.c, process.c} as per Tejun.
2011-01-07Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds1-0/+1
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (416 commits) ARM: DMA: add support for DMA debugging ARM: PL011: add DMA burst threshold support for ST variants ARM: PL011: Add support for transmit DMA ARM: PL011: Ensure IRQs are disabled in UART interrupt handler ARM: PL011: Separate hardware FIFO size from TTY FIFO size ARM: PL011: Allow better handling of vendor data ARM: PL011: Ensure error flags are clear at startup ARM: PL011: include revision number in boot-time port printk ARM: vexpress: add sched_clock() for Versatile Express ARM i.MX53: Make MX53 EVK bootable ARM i.MX53: Some bug fix about MX53 MSL code ARM: 6607/1: sa1100: Update platform device registration ARM: 6606/1: sa1100: Fix platform device registration ARM i.MX51: rename IPU irqs ARM i.MX51: Add ipu clock support ARM: imx/mx27_3ds: Add PMIC support ARM: DMA: Replace page_to_dma()/dma_to_page() with pfn_to_dma()/dma_to_pfn() mx51: fix usb clock support MX51: Add support for usb host 2 arch/arm/plat-mxc/ehci.c: fix errors/typos ...
2010-12-23Fix rounding in clocks_calc_mult_shift()john stultz1-0/+1
Russell King reports: | On the ARM dev boards, we have a 32-bit counter running at 24MHz. Calling | clocks_calc_mult_shift(&mult, &shift, 24MHz, NSEC_PER_SEC, 60) gives | us a multiplier of 2796202666 and a shift of 26. | | Over a large counter delta, this produces an error - lets take a count | from 362976315 to 4280663372: | | (4280663372-362976315) * 2796202666 / 2^26 - (4280663372-362976315) * (1000/24) | => -38.91872422891230269990 | | Can we do better? | | (4280663372-362976315) * 2796202667 / 2^26 - (4280663372-362976315) * (1000/24) | 19.45936211449532822051 | | which is about twice as good as the 2796202666 multiplier. | | Looking at the equivalent divisions obtained, 2796202666 / 2^26 gives | 41.66666665673255920410ns per tick, whereas 2796202667 / 2^26 gives | 41.66666667163372039794ns. The actual value wanted is 1000/24 = | 41.66666666666666666666ns. Fix this by ensuring we round to nearest when calculating the multiplier. Signed-off-by: John Stultz <john.stultz@linaro.org> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Tested-by: Eric Miao <eric.y.miao@gmail.com> Tested-by: Olof Johansson <olof@lixom.net> Tested-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-17core: Replace __get_cpu_var with __this_cpu_read if not used for an address.Christoph Lameter2-3/+3
__get_cpu_var() can be replaced with this_cpu_read and will then use a single read instruction with implied address calculation to access the correct per cpu instance. However, the address of a per cpu variable passed to __this_cpu_read() cannot be determined (since it's an implied address conversion through segment prefixes). Therefore apply this only to uses of __get_cpu_var where the address of the variable is not used. Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Hugh Dickins <hughd@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2010-12-10hrtimers: Convert hrtimers to use timerlist infrastructureJohn Stultz1-4/+4
Converts the hrtimer code to use the new timerlist infrastructure Signed-off-by: John Stultz <john.stultz@linaro.org> LKML Reference: <1290136329-18291-3-git-send-email-john.stultz@linaro.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> CC: Thomas Gleixner <tglx@linutronix.de> CC: Richard Cochran <richardcochran@gmail.com>
2010-11-01tree-wide: fix comment/printk typosUwe Kleine-König1-1/+1
"gadget", "through", "command", "maintain", "maintain", "controller", "address", "between", "initiali[zs]e", "instead", "function", "select", "already", "equal", "access", "management", "hierarchy", "registration", "interest", "relative", "memory", "offset", "already", Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>