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2013-02-21Merge tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds
Pull ARM SoC cleanups from Arnd Bergmann: "A large number of cleanups, all over the platforms. This is dominated largely by the Samsung platforms (s3c, s5p, exynos) and a few of the others moving code out of arch/arm into more appropriate subsystems. The clocksource and irqchip drivers are now abstracted to the point where platforms that are already cleaned up do not need to even specify the driver they use, it can all get configured from the device tree as we do for normal device drivers. The clocksource changes basically touch every single platform in the process. We further clean up the use of platform specific header files here, with the goal of turning more of the platforms over to being "multiplatform" enabled, which implies that they cannot expose their headers to architecture independent code any more. It is expected that no functional changes are part of the cleanup. The overall reduction in total code lines is mostly the result of removing broken and obsolete code." * tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (133 commits) ARM: mvebu: correct gated clock documentation ARM: kirkwood: add missing include for nsa310 ARM: exynos: move exynos4210-combiner to drivers/irqchip mfd: db8500-prcmu: update resource passing drivers/db8500-cpufreq: delete dangling include ARM: at91: remove NEOCORE 926 board sunxi: Cleanup the reset code and add meaningful registers defines ARM: S3C24XX: header mach/regs-mem.h local ARM: S3C24XX: header mach/regs-power.h local ARM: S3C24XX: header mach/regs-s3c2412-mem.h local ARM: S3C24XX: Remove plat-s3c24xx directory in arch/arm/ ARM: S3C24XX: transform s3c2443 subirqs into new structure ARM: S3C24XX: modify s3c2443 irq init to initialize all irqs ARM: S3C24XX: move s3c2443 irq code to irq.c ARM: S3C24XX: transform s3c2416 irqs into new structure ARM: S3C24XX: modify s3c2416 irq init to initialize all irqs ARM: S3C24XX: move s3c2416 irq init to common irq code ARM: S3C24XX: Modify s3c_irq_wake to use the hwirq property ARM: S3C24XX: Move irq syscore-ops to irq-pm clocksource: always define CLOCKSOURCE_OF_DECLARE ...
2013-02-04Merge branch 'fortglx/3.9/time' of git://git.linaro.org/people/jstultz/linux ↵Thomas Gleixner
into timers/core Trivial conflict in arch/x86/Kconfig Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-01-15timekeeping: Add persistent_clock_exist flagFeng Tang
In current kernel, there are several places which need to check whether there is a persistent clock for the platform. Current check is done by calling the read_persistent_clock() and validating its return value. So one optimization is to do the check only once in timekeeping_init(), and use a flag persistent_clock_exist to record it. v2: Add a has_persistent_clock() helper function, as suggested by John. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-01-15time: create __getnstimeofday for WARNless callsKees Cook
The pstore RAM backend can get called during resume, and must be defensive against a suspended time source. Expose getnstimeofday logic that returns an error instead of a WARN. This can be detected and the timestamp can be zeroed out. Reported-by: Doug Anderson <dianders@chromium.org> Cc: John Stultz <johnstul@us.ibm.com> Cc: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-12-24time: convert arch_gettimeoffset to a pointerStephen Warren
Currently, whenever CONFIG_ARCH_USES_GETTIMEOFFSET is enabled, each arch core provides a single implementation of arch_gettimeoffset(). In many cases, different sub-architectures, different machines, or different timer providers exist, and so the arch ends up implementing arch_gettimeoffset() as a call-through-pointer anyway. Examples are ARM, Cris, M68K, and it's arguable that the remaining architectures, M32R and Blackfin, should be doing this anyway. Modify arch_gettimeoffset so that it itself is a function pointer, which the arch initializes. This will allow later changes to move the initialization of this function into individual machine support or timer drivers. This is particularly useful for code in drivers/clocksource which should rely on an arch-independant mechanism to register their implementation of arch_gettimeoffset(). This patch also converts the Cris architecture to set arch_gettimeoffset directly to the final implementation in time_init(), because Cris already had separate time_init() functions per sub-architecture. M68K and ARM are converted to set arch_gettimeoffset to the final implementation in later patches, because they already have function pointers in place for this purpose. Cc: Russell King <linux@arm.linux.org.uk> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Mikael Starvik <starvik@axis.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Stephen Warren <swarren@nvidia.com>
2012-12-13Merge tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Marcelo Tosatti: "Considerable KVM/PPC work, x86 kvmclock vsyscall support, IA32_TSC_ADJUST MSR emulation, amongst others." Fix up trivial conflict in kernel/sched/core.c due to cross-cpu migration notifier added next to rq migration call-back. * tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (156 commits) KVM: emulator: fix real mode segment checks in address linearization VMX: remove unneeded enable_unrestricted_guest check KVM: VMX: fix DPL during entry to protected mode x86/kexec: crash_vmclear_local_vmcss needs __rcu kvm: Fix irqfd resampler list walk KVM: VMX: provide the vmclear function and a bitmap to support VMCLEAR in kdump x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary KVM: MMU: optimize for set_spte KVM: PPC: booke: Get/set guest EPCR register using ONE_REG interface KVM: PPC: bookehv: Add EPCR support in mtspr/mfspr emulation KVM: PPC: bookehv: Add guest computation mode for irq delivery KVM: PPC: Make EPCR a valid field for booke64 and bookehv KVM: PPC: booke: Extend MAS2 EPN mask for 64-bit KVM: PPC: e500: Mask MAS2 EPN high 32-bits in 32/64 tlbwe emulation KVM: PPC: Mask ea's high 32-bits in 32/64 instr emulation KVM: PPC: e500: Add emulation helper for getting instruction ea KVM: PPC: bookehv64: Add support for interrupt handling KVM: PPC: bookehv: Remove GET_VCPU macro from exception handler KVM: PPC: booke: Fix get_tb() compile error on 64-bit KVM: PPC: e500: Silence bogus GCC warning in tlb code ...
2012-11-27time: export time information for KVM pvclockMarcelo Tosatti
As suggested by John, export time data similarly to how its done by vsyscall support. This allows KVM to retrieve necessary information to implement vsyscall support in KVM guests. Acked-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-11-13time: Kill xtime_lock, replacing it with jiffies_lockJohn Stultz
Now that timekeeping is protected by its own locks, rename the xtime_lock to jifffies_lock to better describe what it protects. CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-10-12Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core update from Thomas Gleixner: - Bug fixes (one for a longstanding dead loop issue) - Rework of time related vsyscalls - Alarm timer updates - Jiffies updates to remove compile time dependencies * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Cast raw_interval to u64 to avoid shift overflow timers: Fix endless looping between cascade() and internal_add_timer() time/jiffies: bring back unconditional LATCH definition time: Convert x86_64 to using new update_vsyscall time: Only do nanosecond rounding on GENERIC_TIME_VSYSCALL_OLD systems time: Introduce new GENERIC_TIME_VSYSCALL time: Convert CONFIG_GENERIC_TIME_VSYSCALL to CONFIG_GENERIC_TIME_VSYSCALL_OLD time: Move update_vsyscall definitions to timekeeper_internal.h time: Move timekeeper structure to timekeeper_internal.h for vsyscall changes jiffies: Remove compile time assumptions about CLOCK_TICK_RATE jiffies: Kill unused TICK_USEC_TO_NSEC alarmtimer: Rename alarmtimer_remove to alarmtimer_dequeue alarmtimer: Remove unused helpers & defines alarmtimer: Use hrtimer per-alarm instead of per-base alarmtimer: Implement minimum alarm interval for allowing suspend
2012-10-09timekeeping: Cast raw_interval to u64 to avoid shift overflowDan Carpenter
We fixed a bunch of integer overflows in timekeeping code during the 3.6 cycle. I did an audit based on that and found this potential overflow. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: John Stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/20121009071823.GA19159@elgon.mountain Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org
2012-10-02Merge tag 'pm-for-3.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael J Wysocki: - Improved system suspend/resume and runtime PM handling for the SH TMU, CMT and MTU2 clock event devices (also used by ARM/shmobile). - Generic PM domains framework extensions related to cpuidle support and domain objects lookup using names. - ARM/shmobile power management updates including improved support for the SH7372's A4S power domain containing the CPU core. - cpufreq changes related to AMD CPUs support from Matthew Garrett, Andre Przywara and Borislav Petkov. - cpu0 cpufreq driver from Shawn Guo. - cpufreq governor fixes related to the relaxing of limit from Michal Pecio. - OMAP cpufreq updates from Axel Lin and Richard Zhao. - cpuidle ladder governor fixes related to the disabling of states from Carsten Emde and me. - Runtime PM core updates related to the interactions with the system suspend core from Alan Stern and Kevin Hilman. - Wakeup sources modification allowing more helper functions to be called from interrupt context from John Stultz and additional diagnostic code from Todd Poynor. - System suspend error code path fix from Feng Hong. Fixed up conflicts in cpufreq/powernow-k8 that stemmed from the workqueue fixes conflicting fairly badly with the removal of support for hardware P-state chips. The changes were independent but somewhat intertwined. * tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits) Revert "PM QoS: Use spinlock in the per-device PM QoS constraints code" PM / Runtime: let rpm_resume() succeed if RPM_ACTIVE, even when disabled, v2 cpuidle: rename function name "__cpuidle_register_driver", v2 cpufreq: OMAP: Check IS_ERR() instead of NULL for omap_device_get_by_hwmod_name cpuidle: remove some empty lines PM: Prevent runtime suspend during system resume PM QoS: Use spinlock in the per-device PM QoS constraints code PM / Sleep: use resume event when call dpm_resume_early cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power structure ACPI / processor: remove pointless variable initialization ACPI / processor: remove unused function parameter cpufreq: OMAP: remove loops_per_jiffy recalculate for smp sections: fix section conflicts in drivers/cpufreq cpufreq: conservative: update frequency when limits are relaxed cpufreq / ondemand: update frequency when limits are relaxed properly __init-annotate pm_sysrq_init() cpufreq: Add a generic cpufreq-cpu0 driver PM / OPP: Initialize OPP table from device tree ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp cpufreq: Remove support for hardware P-state chips from powernow-k8 ...
2012-09-24time: Only do nanosecond rounding on GENERIC_TIME_VSYSCALL_OLD systemsJohn Stultz
We only do rounding to the next nanosecond so we don't see minor 1ns inconsistencies in the vsyscall implementations. Since we're changing the vsyscall implementations to avoid this, conditionalize the rounding only to the GENERIC_TIME_VSYSCALL_OLD architectures. Cc: Tony Luck <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-09-24time: Introduce new GENERIC_TIME_VSYSCALLJohn Stultz
Now that we moved everyone over to GENERIC_TIME_VSYSCALL_OLD, introduce the new declaration and config option for the new update_vsyscall method. Cc: Tony Luck <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-09-24time: Convert CONFIG_GENERIC_TIME_VSYSCALL to CONFIG_GENERIC_TIME_VSYSCALL_OLDJohn Stultz
To help migrate archtectures over to the new update_vsyscall method, redfine CONFIG_GENERIC_TIME_VSYSCALL as CONFIG_GENERIC_TIME_VSYSCALL_OLD Cc: Tony Luck <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-09-24time: Move timekeeper structure to timekeeper_internal.h for vsyscall changesJohn Stultz
We're going to need to access the timekeeper in update_vsyscall, so make the structure available for those who need it. Cc: Tony Luck <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-09-13time: Fix timeekeping_get_ns overflow on 32bit systemsJohn Stultz
Daniel Lezcano reported seeing multi-second stalls from keyboard input on his T61 laptop when NOHZ and CPU_IDLE were enabled on a 32bit kernel. He bisected the problem down to commit 1e75fa8be9fb6 ("time: Condense timekeeper.xtime into xtime_sec"). After reproducing this issue, I narrowed the problem down to the fact that timekeeping_get_ns() returns a 64bit nsec value that hasn't been accumulated. In some cases this value was being then stored in timespec.tv_nsec (which is a long). On 32bit systems, with idle times larger then 4 seconds (or less, depending on the value of xtime_nsec), the returned nsec value would overflow 32bits. This limited kept time from increasing, causing timers to not expire. The fix is to make sure we don't directly store the result of timekeeping_get_ns() into a tv_nsec field, instead using a 64bit nsec value which can then be added into the timespec via timespec_add_ns(). Reported-and-bisected-by: Daniel Lezcano <daniel.lezcano@linaro.org> Tested-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Link: http://lkml.kernel.org/r/1347405963-35715-1-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-09-04timekeeping: Add suspend and resume of clock event devicesRafael J. Wysocki
Some clock event devices, for example such that belong to PM domains, need to be handled in a spcial way during the timekeeping suspend and resume (which takes place in the system core, or "syscore", stages of system power transitions) in analogy with clock sources. Introduce .suspend() and .resume() callbacks for clock event devices that will be executed by timekeeping_suspend/_resume(), respectively, next the the clock sources' .suspend() and .resume() callbacks. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-01time: Move ktime_t overflow checking into timespec_valid_strictJohn Stultz
Andreas Bombe reported that the added ktime_t overflow checking added to timespec_valid in commit 4e8b14526ca7 ("time: Improve sanity checking of timekeeping inputs") was causing problems with X.org because it caused timeouts larger then KTIME_T to be invalid. Previously, these large timeouts would be clamped to KTIME_MAX and would never expire, which is valid. This patch splits the ktime_t overflow checking into a new timespec_valid_strict function, and converts the timekeeping codes internal checking to use this more strict function. Reported-and-tested-by: Andreas Bombe <aeb@debian.org> Cc: Zhouping Liu <zliu@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-22time: Avoid making adjustments if we haven't accumulated anythingJohn Stultz
If update_wall_time() is called and the current offset isn't large enough to accumulate, avoid re-calling timekeeping_adjust which may change the clock freq and can cause 1ns inconsistencies with CLOCK_REALTIME_COARSE/CLOCK_MONOTONIC_COARSE. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1345595449-34965-5-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-22time: Avoid potential shift overflow with large shift valuesJohn Stultz
Andreas Schwab noticed that the 1 << tk->shift could overflow if the shift value was greater than 30, since 1 would be a 32bit long on 32bit architectures. This issue was introduced by 1e75fa8be (time: Condense timekeeper.xtime into xtime_sec) Use 1ULL instead to ensure we don't overflow on the shift. Reported-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1345595449-34965-4-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-22time: Fix casting issue in timekeeping_forward_nowAndreas Schwab
arch_gettimeoffset returns a u32 value which when shifted by tk->shift can overflow. This issue was introduced with 1e75fa8be (time: Condense timekeeper.xtime into xtime_sec) Cast it to u64 first. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1345595449-34965-3-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-22time: Ensure we normalize the timekeeper in tk_xtime_addJohn Stultz
Andreas noticed problems with resume on specific hardware after commit 1e75fa8b (time: Condense timekeeper.xtime into xtime_sec) combined with commit b44d50dca (time: Fix casting issue in tk_set_xtime and tk_xtime_add) After some digging I realized we aren't normalizing the timekeeper after the add. Add the missing normalize call. Reported-by: Andreas Schwab <schwab@linux-m68k.org> Tested-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1345595449-34965-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-15time: Improve sanity checking of timekeeping inputsJohn Stultz
Unexpected behavior could occur if the time is set to a value large enough to overflow a 64bit ktime_t (which is something larger then the year 2262). Also unexpected behavior could occur if large negative offsets are injected via adjtimex. So this patch improves the sanity check timekeeping inputs by improving the timespec_valid() check, and then makes better use of timespec_valid() to make sure we don't set the time to an invalid negative value or one that overflows ktime_t. Note: This does not protect from setting the time close to overflowing ktime_t and then letting natural accumulation cause the overflow. Reported-by: CAI Qian <caiqian@redhat.com> Reported-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Zhouping Liu <zliu@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1344454580-17031-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-05time: Fix adjustment cleanup bug in timekeeping_adjust()Ingo Molnar
Tetsuo Handa reported that sporadically the system clock starts counting up too quickly which is enough to confuse the hangcheck timer to print a bogus stall warning. Commit 2a8c0883 "time: Move xtime_nsec adjustment underflow handling timekeeping_adjust" overlooked this exit path: } else return; which should really be a proper exit sequence, fixing the bug as a side effect. Also make the flow more readable by properly balancing curly braces. Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> wrote: Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> wrote: Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: john.stultz@linaro.org Cc: a.p.zijlstra@chello.nl Cc: richardcochran@gmail.com Cc: prarit@redhat.com Link: http://lkml.kernel.org/r/20120804192114.GA28347@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-31time: Remove all direct references to timekeeperJohn Stultz
Ingo noted that the numerous timekeeper.value references made the timekeeping code ugly and caused many long lines that had to be broken up. He recommended replacing timekeeper.value references with tk->value. This patch provides a local tk value for all top level time functions and sets it to &timekeeper. Then all timekeeper access is done via a tk pointer. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1343414893-45779-6-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-31time: Clean up offs_real/wall_to_mono and offs_boot/total_sleep_time updatesJohn Stultz
For performance reasons, we maintain ktime_t based duplicates of wall_to_monotonic (offs_real) and total_sleep_time (offs_boot). Since large problems could occur (such as the resume regression on 3.5-rc7, or the leapsecond hrtimer issue) if these value pairs were to be inconsistently updated, this patch this cleans up how we modify these value pairs to ensure we are always consistent. As a side-effect this is also more efficient as we only caulculate the duplicate values when they are changed, rather then every update_wall_time call. This also provides WARN_ONs to detect if future changes break the invariants. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1343414893-45779-5-git-send-email-john.stultz@linaro.org [ Cleaned up minor style issues. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-31time: Clean up stray newlinesJohn Stultz
Ingo noted inconsistent newline usage between functions. This patch cleans those up. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1343414893-45779-4-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-31Merge branch 'linus' into timers/urgentIngo Molnar
Merge in Linus's branch which already has timers/core merged. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-24time: Fix casting issue in tk_set_xtime and tk_xtime_addJohn Stultz
commit 1e75fa8b (time: Condense timekeeper.xtime into xtime_sec) introduced helper functions which apply a timespec to the core internal timekeeper data. The internal storage type is u64. The timespec tv_nsec value must be shifted before set or added to the internal value. tv_nsec is a long, which is 32bit on a 32bit system, so without casting tv_nsec to u64 we lose the bits which are shifted over the 32bit boundary. Add the proper typecasts. Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1343074957-16541-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-18Merge branch 'linus' into timers/coreIngo Molnar
Resolve semantic conflict in kernel/time/timekeeping.c. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-16timekeeping: Add missing update call in timekeeping_resume()Thomas Gleixner
The leap second rework unearthed another issue of inconsistent data. On timekeeping_resume() the timekeeper data is updated, but nothing calls timekeeping_update(), so now the update code in the timer interrupt sees stale values. This has been the case before those changes, but then the timer interrupt was using stale data as well so this went unnoticed for quite some time. Add the missing update call, so all the data is consistent everywhere. Reported-by: Andreas Schwab <schwab@linux-m68k.org> Reported-and-tested-by: "Rafael J. Wysocki" <rjw@sisk.pl> Reported-and-tested-by: Martin Steigerwald <Martin@lichtvoll.de> Cc: LKML <linux-kernel@vger.kernel.org> Cc: Linux PM list <linux-pm@vger.kernel.org> Cc: John Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, Cc: Prarit Bhargava <prarit@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-15time: Rework timekeeping functions to take timekeeper ptr as argumentJohn Stultz
As part of cleaning up the timekeeping code, this patch converts a number of internal functions to takei a timekeeper ptr as an argument, so that the internal functions don't access the global timekeeper structure directly. This allows for further optimizations to reduce lock hold time later. This patch has been updated to include more consistent usage of the timekeeper value, by making sure it is always passed as a argument to non top-level functions. Signed-off-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-9-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-15time: Move xtime_nsec adjustment underflow handling timekeeping_adjustJohn Stultz
When we make adjustments speeding up the clock, its possible for xtime_nsec to underflow. We already handle this properly, but we do so from update_wall_time() instead of the more logical timekeeping_adjust(), where the possible underflow actually occurs. Thus, move the correction logic to the timekeeping_adjust, which is the function that causes the issue. Making update_wall_time() more readable. Signed-off-by: John Stultz <johnstul@us.ibm.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-8-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-15time: Move arch_gettimeoffset() usage into timekeeping_get_ns()John Stultz
Since we call arch_gettimeoffset() in all the accessor functions, move arch_gettimeoffset() calls into timekeeping_get_ns() and timekeeping_get_ns_raw() to simplify the code. This also makes the code easier to maintain as we don't have to worry about forgetting the arch_gettimeoffset() as has happened in the past. Signed-off-by: John Stultz <johnstul@us.ibm.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-7-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-15time: Refactor accumulation of nsecs to secsJohn Stultz
We do the exact same logic moving nsecs to secs in the timekeeper in multiple places, so condense this into a single function. Signed-off-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-6-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-15time: Condense timekeeper.xtime into xtime_secJohn Stultz
The timekeeper struct has a xtime_nsec, which keeps the sub-nanosecond remainder. This ends up being somewhat duplicative of the timekeeper.xtime.tv_nsec value, and we have to do extra work to keep them apart, copying the full nsec portion out and back in over and over. This patch simplifies some of the logic by taking the timekeeper xtime value and splitting it into timekeeper.xtime_sec and reuses the timekeeper.xtime_nsec for the sub-second portion (stored in higher res shifted nanoseconds). This simplifies some of the accumulation logic. And will allow for more accurate timekeeping once the vsyscall code is updated to use the shifted nanosecond remainder. Signed-off-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-5-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-15time: Explicitly use u32 instead of int for shift valuesJohn Stultz
Ingo noted that using a u32 instead of int for shift values would be better to make sure the compiler doesn't unnecessarily use complex signed arithmetic. Signed-off-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-4-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-15time: Whitespace cleanups per Ingo%27s requestsJohn Stultz
Ingo noted a number of places where there is inconsistent use of whitespace. This patch tries to address the main culprits. Signed-off-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-3-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-11timekeeping: Provide hrtimer update functionThomas Gleixner
To finally fix the infamous leap second issue and other race windows caused by functions which change the offsets between the various time bases (CLOCK_MONOTONIC, CLOCK_REALTIME and CLOCK_BOOTTIME) we need a function which atomically gets the current monotonic time and updates the offsets of CLOCK_REALTIME and CLOCK_BOOTTIME with minimalistic overhead. The previous patch which provides ktime_t offsets allows us to make this function almost as cheap as ktime_get() which is going to be replaced in hrtimer_interrupt(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: John Stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/1341960205-56738-7-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-11timekeeping: Maintain ktime_t based offsets for hrtimersThomas Gleixner
We need to update the hrtimer clock offsets from the hrtimer interrupt context. To avoid conversions from timespec to ktime_t maintain a ktime_t based representation of those offsets in the timekeeper. This puts the conversion overhead into the code which updates the underlying offsets and provides fast accessible values in the hrtimer interrupt. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1341960205-56738-4-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-07-11timekeeping: Fix leapsecond triggered load spike issueJohn Stultz
The timekeeping code misses an update of the hrtimer subsystem after a leap second happened. Due to that timers based on CLOCK_REALTIME are either expiring a second early or late depending on whether a leap second has been inserted or deleted until an operation is initiated which causes that update. Unless the update happens by some other means this discrepancy between the timekeeping and the hrtimer data stays forever and timers are expired either early or late. The reported immediate workaround - $ data -s "`date`" - is causing a call to clock_was_set() which updates the hrtimer data structures. See: http://www.sheeri.com/content/mysql-and-leap-second-high-cpu-and-fix Add the missing clock_was_set() call to update_wall_time() in case of a leap second event. The actual update is deferred to softirq context as the necessary smp function call cannot be invoked from hard interrupt context. Signed-off-by: John Stultz <johnstul@us.ibm.com> Reported-by: Jan Engelhardt <jengelh@inai.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1341960205-56738-3-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-06-04timekeeping: Fix CLOCK_MONOTONIC inconsistency during leapsecondJohn Stultz
Commit 6b43ae8a61 (ntp: Fix leap-second hrtimer livelock) broke the leapsecond update of CLOCK_MONOTONIC. The missing leapsecond update to wall_to_monotonic causes discontinuities in CLOCK_MONOTONIC. Adjust wall_to_monotonic when NTP inserted a leapsecond. Reported-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Tested-by: Richard Cochran <richardcochran@gmail.com> Cc: stable@kernel.org Link: http://lkml.kernel.org/r/1338400497-12420-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-21timekeeping: Fix a few minor newline issues.Richard Cochran
Fix a few minor newline issues. Signed-off-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-29Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core updates from Thomas Gleixner. * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ia64: vsyscall: Add missing paranthesis alarmtimer: Don't call rtc_timer_init() when CONFIG_RTC_CLASS=n x86: vdso: Put declaration before code x86-64: Inline vdso clock_gettime helpers x86-64: Simplify and optimize vdso clock_gettime monotonic variants kernel-time: fix s/then/than/ spelling errors time: remove no_sync_cmos_clock time: Avoid scary backtraces when warning of > 11% adj alarmtimer: Make sure we initialize the rtctimer ntp: Fix leap-second hrtimer livelock x86, tsc: Skip refined tsc calibration on systems with reliable TSC rtc: Provide flag for rtc devices that don't support UIE ia64: vsyscall: Use seqcount instead of seqlock x86: vdso: Use seqcount instead of seqlock x86: vdso: Remove bogus locking in update_vsyscall_tz() time: Remove bogus comments time: Fix change_clocksource locking time: x86: Fix race switching from vsyscall to non-vsyscall clock
2012-03-23kernel-time: fix s/then/than/ spelling errorsJim Cromie
Use than for comparisons, like more than. CC: John Stultz <john.stultz@linaro.org> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-23time: Avoid scary backtraces when warning of > 11% adjJohn Stultz
Folks have been getting a number of warnings about time adjustments > 11%. The WARN_ON leaves a big useless backtrace so this patch removes it for a printk_once(). I'm still working to narrow down the cause of the > 11% adjustment. Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input subsystem updates from Dmitry Torokhov: "- we finally merged driver for USB version of Synaptics touchpads (I guess most commonly found in IBM/Lenovo keyboard/touchpad combo); - a bunch of new drivers for embedded platforms (Cypress touchscreens, DA9052 OnKey, MAX8997-haptic, Ilitek ILI210x touchscreens, TI touchscreen); - input core allows clients to specify desired clock source for timestamps on input events (EVIOCSCLOCKID ioctl); - input core allows querying state of all MT slots for given event code via EVIOCGMTSLOTS ioctl; - various driver fixes and improvements." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (45 commits) Input: ili210x - add support for Ilitek ILI210x based touchscreens Input: altera_ps2 - use of_match_ptr() Input: synaptics_usb - switch to module_usb_driver() Input: convert I2C drivers to use module_i2c_driver() Input: convert SPI drivers to use module_spi_driver() Input: omap4-keypad - move platform_data to <linux/platform_data> Input: kxtj9 - who_am_i check value and initial data rate fixes Input: add driver support for MAX8997-haptic Input: tegra-kbc - revise device tree support Input: of_keymap - add device tree bindings for simple key matrices Input: wacom - fix physical size calculation for 3rd-gen Bamboo Input: twl4030-vibra - really switch from #if to #ifdef Input: hp680_ts_input - ensure arguments to request_irq and free_irq are compatible Input: max8925_onkey - avoid accessing input device too early Input: max8925_onkey - allow to be used as a wakeup source Input: atmel-wm97xx - convert to dev_pm_ops Input: atmel-wm97xx - set driver owner Input: add cyttsp touchscreen maintainer entry Input: cyttsp - remove useless checks in cyttsp_probe() Input: usbtouchscreen - add support for Data Modul EasyTouch TP 72037 ...
2012-03-22ntp: Fix leap-second hrtimer livelockJohn Stultz
Since commit 7dffa3c673fbcf835cd7be80bb4aec8ad3f51168 the ntp subsystem has used an hrtimer for triggering the leapsecond adjustment. However, this can cause a potential livelock. Thomas diagnosed this as the following pattern: CPU 0 CPU 1 do_adjtimex() spin_lock_irq(&ntp_lock); process_adjtimex_modes(); timer_interrupt() process_adj_status(); do_timer() ntp_start_leap_timer(); write_lock(&xtime_lock); hrtimer_start(); update_wall_time(); hrtimer_reprogram(); ntp_tick_length() tick_program_event() spin_lock(&ntp_lock); clockevents_program_event() ktime_get() seq = req_seqbegin(xtime_lock); This patch tries to avoid the problem by reverting back to not using an hrtimer to inject leapseconds, and instead we handle the leapsecond processing in the second_overflow() function. The downside to this change is that on systems that support highres timers, the leap second processing will occur on a HZ tick boundary, (ie: ~1-10ms, depending on HZ) after the leap second instead of possibly sooner (~34us in my tests w/ x86_64 lapic). This patch applies on top of tip/timers/core. CC: Sasha Levin <levinsasha928@gmail.com> CC: Thomas Gleixner <tglx@linutronix.de> Reported-by: Sasha Levin <levinsasha928@gmail.com> Diagnoised-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-15time: Fix change_clocksource lockingJohn Stultz
change_clocksource() fails to grab locks or call timekeeping_update(), which leaves a race window for time inconsistencies. This adds proper locking and a call to timekeeping_update() to fix this. CC: Andy Lutomirski <luto@amacapital.net> CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-09Merge commit 'v3.3-rc6' into nextDmitry Torokhov