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2015-06-12ntp: Do leapsecond adjustment in adjtimex read pathJohn Stultz1-0/+18
Since the leapsecond is applied at tick-time, this means there is a small window of time at the start of a leap-second where we cross into the next second before applying the leap. This patch modified adjtimex so that the leap-second is applied on the second edge. Providing more correct leapsecond behavior. This does make it so that adjtimex()'s returned time values can be inconsistent with time values read from gettimeofday() or clock_gettime(CLOCK_REALTIME,...) for a brief period of one tick at the leapsecond. However, those other interfaces do not provide the TIME_OOP time_state return that adjtimex() provides, which allows the leapsecond to be properly represented. They instead only see a time discontinuity, and cannot tell the first 23:59:59 from the repeated 23:59:59 leap second. This seems like a reasonable tradeoff given clock_gettime() / gettimeofday() cannot properly represent a leapsecond, and users likely care more about performance, while folks who are using adjtimex() more likely care about leap-second correctness. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Jiri Bohac <jbohac@suse.cz> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1434063297-28657-5-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-12time: Prevent early expiry of hrtimers[CLOCK_REALTIME] at the leap second edgeJohn Stultz5-8/+61
Currently, leapsecond adjustments are done at tick time. As a result, the leapsecond was applied at the first timer tick *after* the leapsecond (~1-10ms late depending on HZ), rather then exactly on the second edge. This was in part historical from back when we were always tick based, but correcting this since has been avoided since it adds extra conditional checks in the gettime fastpath, which has performance overhead. However, it was recently pointed out that ABS_TIME CLOCK_REALTIME timers set for right after the leapsecond could fire a second early, since some timers may be expired before we trigger the timekeeping timer, which then applies the leapsecond. This isn't quite as bad as it sounds, since behaviorally it is similar to what is possible w/ ntpd made leapsecond adjustments done w/o using the kernel discipline. Where due to latencies, timers may fire just prior to the settimeofday call. (Also, one should note that all applications using CLOCK_REALTIME timers should always be careful, since they are prone to quirks from settimeofday() disturbances.) However, the purpose of having the kernel do the leap adjustment is to avoid such latencies, so I think this is worth fixing. So in order to properly keep those timers from firing a second early, this patch modifies the ntp and timekeeping logic so that we keep enough state so that the update_base_offsets_now accessor, which provides the hrtimer core the current time, can check and apply the leapsecond adjustment on the second edge. This prevents the hrtimer core from expiring timers too early. This patch does not modify any other time read path, so no additional overhead is incurred. However, this also means that the leap-second continues to be applied at tick time for all other read-paths. Apologies to Richard Cochran, who pushed for similar changes years ago, which I resisted due to the concerns about the performance overhead. While I suspect this isn't extremely critical, folks who care about strict leap-second correctness will likely want to watch this. Potentially a -stable candidate eventually. Originally-suggested-by: Richard Cochran <richardcochran@gmail.com> Reported-by: Daniel Bristot de Oliveira <bristot@redhat.com> Reported-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Jiri Bohac <jbohac@suse.cz> Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1434063297-28657-4-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-12ntp: Introduce and use SECS_PER_DAY macro instead of 86400John Stultz1-2/+3
Currently the leapsecond logic uses what looks like magic values. Improve this by defining SECS_PER_DAY and using that macro to make the logic more clear. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Jiri Bohac <jbohac@suse.cz> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1434063297-28657-3-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-12time: Move clock_was_set_seq update before updating shadow-timekeeperJohn Stultz1-4/+8
It was reported that 868a3e915f7f5eba (hrtimer: Make offset update smarter) was causing timer problems after suspend/resume. The problem with that change is the modification to clock_was_set_seq in timekeeping_update is done prior to mirroring the time state to the shadow-timekeeper. Thus the next time we do update_wall_time() the updated sequence is overwritten by whats in the shadow copy. This patch moves the shadow-timekeeper mirroring to the end of the function, after all updates have been made, so all data is kept in sync. (This patch also affects the update_fast_timekeeper calls which were also problematically done prior to the mirroring). Reported-and-tested-by: Jeremiah Mahler <jmmahler@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/1434063297-28657-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-10clocksource: Use current logging styleJoe Perches1-12/+12
clocksource messages aren't prefixed in dmesg so it's a bit unclear what subsystem emits the messages. Use pr_fmt and pr_<level> to auto-prefix the messages appropriately. Miscellanea: o Remove "Warning" from KERN_WARNING level messages o Align "timekeeping watchdog: " messages o Coalesce formats o Align multiline arguments Signed-off-by: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/1432579795.2846.75.camel@perches.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-10time: Allow gcc to fold usecs_to_jiffies(constant)Nicholas Mc Guire1-1/+29
To allow constant folding in usecs_to_jiffies() conditionally calls the HZ dependent _usecs_to_jiffies() helpers or, when gcc can not figure out constant folding, __usecs_to_jiffies, which is the renamed original usecs_to_jiffies() function. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1432832996-12129-2-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-10time: Refactor usecs_to_jiffiesNicholas Mc Guire2-11/+29
Refactor the usecs_to_jiffies conditional code part in time.c and jiffies.h putting it into conditional functions rather than #ifdefs to improve readability. This is analogous to the msecs_to_jiffies() cleanup in commit ca42aaf0c861 ("time: Refactor msecs_to_jiffies") Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1432832996-12129-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-08hrtimers: Make sure hrtimer_resolution is unsigned intBorislav Petkov1-1/+1
... in the !CONFIG_HIGH_RES_TIMERS case too. And thus fix warnings like this one: net/sched/sch_api.c: In function ‘psched_show’: net/sched/sch_api.c:1891:6: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 6 has type ‘long int’ [-Wformat=] (u32)NSEC_PER_SEC / hrtimer_resolution); Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1433583000-32090-1-git-send-email-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de>
2015-06-02Merge branch 'clockevents/4.2' of ↵Thomas Gleixner10-78/+632
http://git.linaro.org/people/daniel.lezcano/linux into timers/core Pull clockevents/clocksource changes from Daniel Lezcano: - Removed dead code in the files related to mach-msm for qcom (Stephen Boyd) - Cleaned up code for exynos_mct (Krzysztof Kozlowski) - Added the new timer lpc3220 (Joachim Eastwood) - Added the new timer STM32 and ARM system timer (Maxime Coquelin)
2015-06-02clockevents: Rename state to state_use_accessorsThomas Gleixner2-9/+9
The only sensible way to make abuse of core internal fields obvious and easy to grep for. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org>
2015-06-02clockevents: Use set/get state helper functionsThomas Gleixner2-6/+7
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org>
2015-06-02clockevents: Provide functions to set and get the stateThomas Gleixner5-24/+35
We want to rename dev->state, so provide proper get and set functions. Rename clockevents_set_state() to clockevents_switch_state() to avoid confusion. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org>
2015-06-02clockevents: Use helpers to check the state of a clockevent deviceViresh Kumar4-17/+17
Use accessor functions to check the state of clockevent devices in core code. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: linaro-kernel@lists.linaro.org Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/fa2b9869fd17f210eaa156ec2b594efd0230b6c7.1432192527.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-02clockevents: Add helpers to check the state of a clockevent deviceViresh Kumar1-0/+26
Some clockevent drivers, once migrated to use per-state callbacks, need to check the state of the clockevent device in their callbacks or interrupt handler. Add accessor functions clockevent_state_*() to get this information. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: linaro-kernel@lists.linaro.org Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/04a717d490335c688dd7af899fbcede97e1bb8ee.1432192527.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-02clockevents/drivers/timer-stm32: Fix build warning spotted by kbuild test robotMaxime Coquelin1-2/+2
This patch fixes below warning spotted by kbuild test robot when building with ARCH=powerpc: drivers/clocksource/timer-stm32.c: In function 'stm32_clockevent_init': >> drivers/clocksource/timer-stm32.c:140:9: warning: large integer implicitly truncated to unsigned type [-Woverflow] writel_relaxed(~0UL, data->base + TIM_ARR); The fix consists in using 0U instead of 0UL. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02clockevents/drivers: Add STM32 Timer driverMaxime Coquelin3-0/+190
STM32 MCUs feature 16 and 32 bits general purpose timers with prescalers. The drivers detects whether the time is 16 or 32 bits, and applies a 1024 prescaler value if it is 16 bits. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02dt-bindings: Document the STM32 timer bindingsMaxime Coquelin1-0/+22
This adds documentation of device tree bindings for the STM32 timer. Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02clocksource/drivers/armv7m_systick: Add ARM System timer driverMaxime Coquelin3-0/+87
This patch adds clocksource support for ARMv7-M's System timer, also known as SysTick. Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02dt-bindings: Document the ARM System timer bindingsMaxime Coquelin1-0/+26
This adds documentation of device tree bindings for the ARM System timer. Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02doc: dt: Add documentation for lpc3220-timerJoachim Eastwood1-0/+26
Add DT bindings documentation for lpc3220-timer. This timer is used as clocksource on many NXP platforms. Signed-off-by: Joachim Eastwood <manabian@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-06-02clocksource/drivers/lpc32xx: Add the lpc32xx timer driverJoachim Eastwood3-0/+278
Add support for using the NXP LPC timer as clocksource and clock event. These timers are present on many NXP devices including LPC32xx, LPC17xx, LPC18xx and LPC43xx. The timer has a 32-bit timer counter register with a programmable 32-bit prescaler. It supports up to 4 compare match values with interrupt generation and reset/stop timer counter action. Signed-off-by: Joachim Eastwood <manabian@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-06-02clocksource/drivers/exynos_mct: Remove old platform mct_init()Krzysztof Kozlowski1-12/+0
Since commit 228e3023eb04 ("Merge tag 'mct-exynos-for-v3.10' of ...") the mct_init() was superseded by mct_init_dt() and is not referenced anywhere. Remove it. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02clocksource/drivers/exynos_mct: Staticize struct clocksourceKrzysztof Kozlowski1-1/+1
The struct clocksource 'mct_frc' is not exported and used outside so make it static. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02clocksource/drivers/exynos_mct: Change exynos4_mct_tick_clear return type to ↵Krzysztof Kozlowski1-6/+2
void Return value of exynos4_mct_tick_clear() was never checked so it can be safely changed to void. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02clocksource/drivers/qcom: Remove dead codeStephen Boyd1-59/+0
This code is no longer used now that mach-msm has been removed. Delete it. Cc: David Brown <davidb@codeaurora.org> Cc: Bryan Huntsman <bryanh@codeaurora.org> Cc: Daniel Walker <dwalker@fifo99.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-05-27clockevents: Do not suspend/resume if unusedAlexandre Belloni1-2/+2
There is no point in calling suspend/resume for unused clockevents as they are already stopped and disabled. This is really important for AT91 as the hardware is a trainwreck and takes ages to synchronize. Reported-by: Sylvain Rochet <sylvain.rochet@finsecur.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Cc: Maxime Ripard <maxime.ripard@free-electrons.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1421399151-26800-1-git-send-email-alexandre.belloni@free-electrons.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-22time: Remove read_boot_clock()Xunlei Pang2-12/+3
Now that we have a read_boot_clock64() function available on every architecture, and converted all the users to it, it's time to remove the (now unused) read_boot_clock() completely from the kernel. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org> [jstultz: Minor commit message tweak suggested by Ingo] Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-22s390: time: Provide read_boot_clock64() and read_persistent_clock64()Xunlei Pang3-10/+12
As part of addressing the "y2038 problem" for in-kernel uses, this patch converts read_boot_clock() to read_boot_clock64() and read_persistent_clock() to read_persistent_clock64() using timespec64. Rename some instances of 'timespec' to 'timespec64' in time.c and related references Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org> [jstultz: Fixed minor style and grammer tweaks pointed out by Ingo] Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-22time: Include math64.h in time64.hXunlei Pang1-0/+1
On 32-bit systems, timespec64_add_ns() calls __iter_div_u64_rem() which needs math64.h, and we want to include time64.h in some cases. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-22tracing: timer: Add deferrable flag to timer_startBadhri Jagan Sridharan2-5/+10
The timer_start event now shows whether the timer is deferrable in case of a low-res timer. The debug_activate function now includes a deferrable flag while calling the trace_timer_start event. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Badhri Jagan Sridharan <Badhri@google.com> [jstultz: Fixed minor whitespace and grammer tweaks pointed out by Ingo] Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-22time: Rework debugging variables so they aren't globalJohn Stultz2-22/+26
Ingo suggested that the timekeeping debugging variables recently added should not be global, and should be tied to the timekeeper's read_base. Thus this patch implements that suggestion. This version is different from the earlier versions as it keeps the variables in the timekeeper structure rather then in the tkr. Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-22timekeeping: Provide new API to get the current time resolutionHarald Geyer2-0/+18
This patch series introduces a new function u32 ktime_get_resolution_ns(void) which allows to clean up some driver code. In particular the IIO subsystem has a function to provide timestamps for events but no means to get their resolution. So currently the dht11 driver tries to guess the resolution in a rather messy and convoluted way. We can do much better with the new code. This API is not designed to be exposed to user space. This has been tested on i386, sunxi and mxs. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Harald Geyer <harald@ccbib.org> [jstultz: Tweaked to make it build after upstream changes] Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-22time: Make sure tz_minuteswest is set to a valid value when setting timeSasha Levin1-0/+4
Invalid values may overflow later, leading to undefined behaviour when multiplied by 60 to get the amount of seconds. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-19jiffies: Remove the extra indentation levelThomas Gleixner1-8/+7
Somehow I missed to clean that up when applying the patches. Fix it up now. Reported-by: Joe Perches <joe@perches.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Nicholas Mc Guire <der.herr@hofr.at>
2015-05-19clockevents: Stop unused clockevent devicesViresh Kumar3-4/+22
To avoid getting spurious interrupts on a tickless CPU, clockevent device can now be stopped by switching to ONESHOT_STOPPED state. The natural place for handling this transition is tick_program_event(). On 'expires == KTIME_MAX', we skip programming the event and so we need to fix such call sites as well, to always call tick_program_event() irrespective of the expires value. Once the clockevent device is required again, check if it was earlier put into ONESHOT_STOPPED state. If yes, switch its state to ONESHOT before programming its event. To make sure we haven't missed any corner case, add a WARN() for the case where we try to reprogram clockevent device while we aren't configured in ONESHOT_STOPPED state. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: linaro-kernel@lists.linaro.org Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5146b07be7f0bc497e0ebae036590ec2fa73e540.1428031396.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-19clockevents: Introduce CLOCK_EVT_STATE_ONESHOT_STOPPED stateViresh Kumar3-2/+25
When no timers/hrtimers are pending, the expiry time is set to a special value: 'KTIME_MAX'. This normally happens with NO_HZ_{IDLE|FULL} in both LOWRES/HIGHRES modes. When 'expiry == KTIME_MAX', we either cancel the 'tick-sched' hrtimer (NOHZ_MODE_HIGHRES) or skip reprogramming clockevent device (NOHZ_MODE_LOWRES). But, the clockevent device is already reprogrammed from the tick-handler for next tick. As the clock event device is programmed in ONESHOT mode it will at least fire one more time (unnecessarily). Timers on few implementations (like arm_arch_timer, etc.) only support PERIODIC mode and their drivers emulate ONESHOT over that. Which means that on these platforms we will get spurious interrupts periodically (at last programmed interval rate, normally tick rate). In order to avoid spurious interrupts, the clockevent device should be stopped or its interrupts should be masked. A simple (yet hacky) solution to get this fixed could be: update hrtimer_force_reprogram() to always reprogram clockevent device and update clockevent drivers to STOP generating events (or delay it to max time) when 'expires' is set to KTIME_MAX. But the drawback here is that every clockevent driver has to be hacked for this particular case and its very easy for new ones to miss this. However, Thomas suggested to add an optional state ONESHOT_STOPPED to solve this problem: lkml.org/lkml/2014/5/9/508. This patch adds support for ONESHOT_STOPPED state in clockevents core. It will only be available to drivers that implement the state-specific callbacks instead of the legacy ->set_mode() callback. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com> Cc: linaro-kernel@lists.linaro.org Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/b8b383a03ac07b13312c16850b5106b82e4245b5.1428031396.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-19Merge branch 'linus' into timers/coreThomas Gleixner3182-65651/+108603
Make sure the upstream fixes are applied before adding further modifications.
2015-05-19time: Allow gcc to fold constants when possibleNicholas Mc Guire1-3/+15
To allow constant folding in msecs_to_jiffies() conditionally calls the HZ dependent _msecs_to_jiffies() helpers or, when gcc can not figure out constant folding, __msecs_to_jiffies which is the renamed original msecs_to_jiffies() function. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-3-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-19time: Refactor msecs_to_jiffiesNicholas Mc Guire2-41/+82
Refactor the msecs_to_jiffies conditional code part in time.c and jiffies.h putting it into conditional functions rather than #ifdefs to improve readability. [ tglx: Verified that there is no binary code change ] Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-2-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-19time: Move timeconst.h into include/generatedNicholas Mc Guire4-25/+31
kernel/time/timeconst.h is moved to include/generated/ and generated by the top level Kbuild. This allows using timeconst.h in an earlier build stage. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-18Linux 4.1-rc4Linus Torvalds1-1/+1
2015-05-18watchdog: Fix merge 'conflict'Peter Zijlstra1-5/+15
Two watchdog changes that came through different trees had a non conflicting conflict, that is, one changed the semantics of a variable but no actual code conflict happened. So the merge appeared fine, but the resulting code did not behave as expected. Commit 195daf665a62 ("watchdog: enable the new user interface of the watchdog mechanism") changes the semantics of watchdog_user_enabled, which thereafter is only used by the functions introduced by b3738d293233 ("watchdog: Add watchdog enable/disable all functions"). There further appears to be a distinct lack of serialization between setting and using watchdog_enabled, so perhaps we should wrap the {en,dis}able_all() things in watchdog_proc_mutex. This patch fixes a s2r failure reported by Michal; which I cannot readily explain. But this does make the code internally consistent again. Reported-and-tested-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-05-18Merge tag 'for-linus-20150516' of git://git.infradead.org/linux-mtdLinus Torvalds3-8/+10
Pull MTD fixes from Brian Norris: "Two MTD fixes for 4.1: - readtest: the signal-handling code was clobbering the error codes we should be handling/reporting in this test, rendering it useless. Noticed by Coverity. - the common SPI NOR flash DT binding (merged for 4.1-rc1) is being revised, so let's change that before 4.1 is minted" * tag 'for-linus-20150516' of git://git.infradead.org/linux-mtd: Documentation: dt: mtd: replace "nor-jedec" binding with "jedec, spi-nor" mtd: readtest: don't clobber error reports
2015-05-18sched,perf: Fix periodic timersPeter Zijlstra6-33/+42
In the below two commits (see Fixes) we have periodic timers that can stop themselves when they're no longer required, but need to be (re)-started when their idle condition changes. Further complications is that we want the timer handler to always do the forward such that it will always correctly deal with the overruns, and we do not want to race such that the handler has already decided to stop, but the (external) restart sees the timer still active and we end up with a 'lost' timer. The problem with the current code is that the re-start can come before the callback does the forward, at which point the forward from the callback will WARN about forwarding an enqueued timer. Now, conceptually its easy to detect if you're before or after the fwd by comparing the expiration time against the current time. Of course, that's expensive (and racy) because we don't have the current time. Alternatively one could cache this state inside the timer, but then everybody pays the overhead of maintaining this extra state, and that is undesired. The only other option that I could see is the external timer_active variable, which I tried to kill before. I would love a nicer interface for this seemingly simple 'problem' but alas. Fixes: 272325c4821f ("perf: Fix mux_interval hrtimer wreckage") Fixes: 77a4d1a1b9a1 ("sched: Cleanup bandwidth timers") Cc: pjt@google.com Cc: tglx@linutronix.de Cc: klamm@yandex-team.ru Cc: mingo@kernel.org Cc: bsegall@google.com Cc: hpa@zytor.com Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/20150514102311.GX21418@twins.programming.kicks-ass.net
2015-05-17Merge tag 'usb-4.1-rc4' of ↵Linus Torvalds38-140/+171
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "Here are some USB fixes and new device ids for 4.1-rc4. All are pretty minor, and have been in linux-next successfully" * tag 'usb-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: usb-storage: Add NO_WP_DETECT quirk for Lacie 059f:0651 devices Added another USB product ID for ELAN touchscreen quirks. xhci: gracefully handle xhci_irq dead device xhci: Solve full event ring by increasing TRBS_PER_SEGMENT to 256 xhci: fix isoc endpoint dequeue from advancing too far on transaction error usb: chipidea: debug: avoid out of bound read USB: visor: Match I330 phone more precisely USB: pl2303: Remove support for Samsung I330 USB: cp210x: add ID for KCF Technologies PRN device usb: gadget: remove incorrect __init/__exit annotations usb: phy: isp1301: work around tps65010 dependency usb: gadget: serial: fix re-ordering of tx data usb: gadget: hid: Fix static variable usage usb: gadget: configfs: Fix interfaces array NULL-termination usb: gadget: xilinx: fix devm_ioremap_resource() check usb: dwc3: dwc3-omap: correct the register macros
2015-05-17Merge tag 'tty-4.1-rc4' of ↵Linus Torvalds10-34/+64
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial fixes from Greg KH: "Here's some TTY and serial driver fixes for reported issues. All of these have been in linux-next successfully" * tag 'tty-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: pty: Fix input race when closing tty/n_gsm.c: fix a memory leak when gsmtty is removed Revert "serial/amba-pl011: Leave the TX IRQ alone when the UART is not open" serial: omap: Fix error handling in probe earlycon: Revert log warnings
2015-05-17Merge tag 'staging-4.1-rc4' of ↵Linus Torvalds24-110/+152
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging / IIO driver fixes from Greg KH: "Here's some staging and iio driver fixes to resolve a number of reported issues. All of these have been in linux-next for a while" * tag 'staging-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (31 commits) iio: light: hid-sensor-prox: Fix memory leak in probe() iio: adc: cc10001: Add delay before setting START bit iio: adc: cc10001: Fix regulator_get_voltage() return value check iio: adc: cc10001: Fix incorrect use of power-up/power-down register staging: gdm724x: Correction of variable usage after applying ALIGN() iio: adc: cc10001: Fix the channel number mapping staging: vt6655: lock MACvWriteBSSIDAddress. staging: vt6655: CARDbUpdateTSF bss timestamp correct tsf counter value. staging: vt6655: vnt_tx_packet Correct TX order of OWNED_BY_NIC staging: vt6655: Fix 80211 control and management status reporting. staging: vt6655: implement IEEE80211_TX_STAT_NOACK_TRANSMITTED staging: vt6655: device_free_tx_buf use only ieee80211_tx_status_irqsafe staging: vt6656: use ieee80211_tx_info to select packet type. staging: rtl8712: freeing an ERR_PTR staging: sm750: remove incorrect __exit annotation iio: kfifo: Set update_needed to false only if a buffer was allocated iio: mcp320x: Fix occasional incorrect readings iio: accel: mma9553: check input value for activity period iio: accel: mma9553: add enable channel for activity iio: accel: mma9551_core: prevent buffer overrun ...
2015-05-17Merge tag 'char-misc-4.1-rc4' of ↵Linus Torvalds1-12/+12
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc fix from Greg KH: "Here is one fix, in the extcon subsystem, that resolves a reported issue. It's been in linux-next for a number of weeks now, sorry for not getting it to you sooner" * tag 'char-misc-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: extcon: usb-gpio: register extcon device before IRQ registration
2015-05-17Merge branch 'for-linus-4.1-rc4' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML hostfs fix from Richard Weinberger: "This contains a single fix for a regression introduced in 4.1-rc1" * 'for-linus-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: hostfs: Use correct mask for file mode
2015-05-17Merge tag 'upstream-4.1-rc4' of git://git.infradead.org/linux-ubifsLinus Torvalds1-0/+2
Pull UBI bufix from Richard Weinberger: "This contains a single bug fix for the UBI block driver" * tag 'upstream-4.1-rc4' of git://git.infradead.org/linux-ubifs: UBI: block: Add missing cache flushes