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* time: Make sure jiffies_to_msecs() preserves non-zero time periodsGeert Uytterhoeven2018-06-221-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For the common cases where 1000 is a multiple of HZ, or HZ is a multiple of 1000, jiffies_to_msecs() never returns zero when passed a non-zero time period. However, if HZ > 1000 and not an integer multiple of 1000 (e.g. 1024 or 1200, as used on alpha and DECstation), jiffies_to_msecs() may return zero for small non-zero time periods. This may break code that relies on receiving back a non-zero value. jiffies_to_usecs() does not need such a fix: one jiffy can only be less than one µs if HZ > 1000000, and such large values of HZ are already rejected at build time, twice: - include/linux/jiffies.h does #error if HZ >= 12288, - kernel/time/time.c has BUILD_BUG_ON(HZ > USEC_PER_SEC). Broken since forever. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Stephen Boyd <sboyd@kernel.org> Cc: linux-alpha@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180622143357.7495-1-geert@linux-m68k.org
* posix-timers: Fix nanosleep_copyout() for CONFIG_COMPAT_32BIT_TIMEArnd Bergmann2018-06-191-1/+1
| | | | | | | | | | | | | | | | | | | Commit b5793b0d92c9 added support for building the nanosleep compat system call on 32-bit architectures, but missed one change in nanosleep_copyout(), which would trigger a BUG() as soon as any architecture is switched over to use it. Use the proper config symbol to enable the code path. Fixes: Commit b5793b0d92c9 ("posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: y2038@lists.linaro.org Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Deepa Dinamani <deepa.kernel@gmail.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Link: https://lkml.kernel.org/r/20180618140811.2998503-1-arnd@arndb.de
* posix-cpu-timers: Remove lockdep_assert_irqs_disabled()Sebastian Andrzej Siewior2018-06-121-2/+0
| | | | | | | | | | | | | | | | The lockdep_assert_irqs_disabled() was a BUG_ON() statement in the beginning and it was added just before the "spin_lock(siglock)" statement to ensure this lock was taken with disabled interrupts. This is no longer the case: the siglock is acquired via lock_task_sighand() and this function already disables the interrupts. The lock is also acquired before this "lockdep_assert_irqs_disabled" so it is best to remove it. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Frederic Weisbecker <frederic@kernel.org> Link: https://lkml.kernel.org/r20180504152548.7166-1-bigeasy@linutronix.de
* Merge tag 'pm-4.18-rc1' of ↵Linus Torvalds2018-06-051-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These include a significant update of the generic power domains (genpd) and Operating Performance Points (OPP) frameworks, mostly related to the introduction of power domain performance levels, cpufreq updates (new driver for Qualcomm Kryo processors, updates of the existing drivers, some core fixes, schedutil governor improvements), PCI power management fixes, ACPI workaround for EC-based wakeup events handling on resume from suspend-to-idle, and major updates of the turbostat and pm-graph utilities. Specifics: - Introduce power domain performance levels into the the generic power domains (genpd) and Operating Performance Points (OPP) frameworks (Viresh Kumar, Rajendra Nayak, Dan Carpenter). - Fix two issues in the runtime PM framework related to the initialization and removal of devices using device links (Ulf Hansson). - Clean up the initialization of drivers for devices in PM domains (Ulf Hansson, Geert Uytterhoeven). - Fix a cpufreq core issue related to the policy sysfs interface causing CPU online to fail for CPUs sharing one cpufreq policy in some situations (Tao Wang). - Make it possible to use platform-specific suspend/resume hooks in the cpufreq-dt driver and make the Armada 37xx DVFS use that feature (Viresh Kumar, Miquel Raynal). - Optimize policy transition notifications in cpufreq (Viresh Kumar). - Improve the iowait boost mechanism in the schedutil cpufreq governor (Patrick Bellasi). - Improve the handling of deferred frequency updates in the schedutil cpufreq governor (Joel Fernandes, Dietmar Eggemann, Rafael Wysocki, Viresh Kumar). - Add a new cpufreq driver for Qualcomm Kryo (Ilia Lin). - Fix and clean up some cpufreq drivers (Colin Ian King, Dmitry Osipenko, Doug Smythies, Luc Van Oostenryck, Simon Horman, Viresh Kumar). - Fix the handling of PCI devices with the DPM_SMART_SUSPEND flag set and update stale comments in the PCI core PM code (Rafael Wysocki). - Work around an issue related to the handling of EC-based wakeup events in the ACPI PM core during resume from suspend-to-idle if the EC has been put into the low-power mode (Rafael Wysocki). - Improve the handling of wakeup source objects in the PM core (Doug Berger, Mahendran Ganesh, Rafael Wysocki). - Update the driver core to prevent deferred probe from breaking suspend/resume ordering (Feng Kan). - Clean up the PM core somewhat (Bjorn Helgaas, Ulf Hansson, Rafael Wysocki). - Make the core suspend/resume code and cpufreq support the RT patch (Sebastian Andrzej Siewior, Thomas Gleixner). - Consolidate the PM QoS handling in cpuidle governors (Rafael Wysocki). - Fix a possible crash in the hibernation core (Tetsuo Handa). - Update the rockchip-io Adaptive Voltage Scaling (AVS) driver (David Wu). - Update the turbostat utility (fixes, cleanups, new CPU IDs, new command line options, built-in "Low Power Idle" counters support, new POLL and POLL% columns) and add an entry for it to MAINTAINERS (Len Brown, Artem Bityutskiy, Chen Yu, Laura Abbott, Matt Turner, Prarit Bhargava, Srinivas Pandruvada). - Update the pm-graph to version 5.1 (Todd Brandt). - Update the intel_pstate_tracer utility (Doug Smythies)" * tag 'pm-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (128 commits) tools/power turbostat: update version number tools/power turbostat: Add Node in output tools/power turbostat: add node information into turbostat calculations tools/power turbostat: remove num_ from cpu_topology struct tools/power turbostat: rename num_cores_per_pkg to num_cores_per_node tools/power turbostat: track thread ID in cpu_topology tools/power turbostat: Calculate additional node information for a package tools/power turbostat: Fix node and siblings lookup data tools/power turbostat: set max_num_cpus equal to the cpumask length tools/power turbostat: if --num_iterations, print for specific number of iterations tools/power turbostat: Add Cannon Lake support tools/power turbostat: delete duplicate #defines x86: msr-index.h: Correct SNB_C1/C3_AUTO_UNDEMOTE defines tools/power turbostat: Correct SNB_C1/C3_AUTO_UNDEMOTE defines tools/power turbostat: add POLL and POLL% column tools/power turbostat: Fix --hide Pk%pc10 tools/power turbostat: Build-in "Low Power Idle" counters support tools/power turbostat: Don't make man pages executable tools/power turbostat: remove blank lines tools/power turbostat: a small C-states dump readability immprovement ...
| * PM / suspend: Prevent might sleep splatsThomas Gleixner2018-05-271-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | timekeeping suspend/resume calls read_persistent_clock() which takes rtc_lock. That results in might sleep warnings because at that point we run with interrupts disabled. We cannot convert rtc_lock to a raw spinlock as that would trigger other might sleep warnings. As a workaround we disable the might sleep warnings by setting system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and restoring it to SYSTEM_RUNNING afer sysdev_resume(). There is no lock contention because hibernate / suspend to RAM is single-CPU at this point. In s2idle's case the system_state is set to SYSTEM_SUSPEND before timekeeping_suspend() which is invoked by the last CPU. In the resume case it set back to SYSTEM_RUNNING after timekeeping_resume() which is invoked by the first CPU in the resume case. The other CPUs will block on tick_freeze_lock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [bigeasy: cover s2idle in tick_freeze() / tick_unfreeze()] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | Merge branch 'timers-2038-for-linus' of ↵Linus Torvalds2018-06-052-41/+34
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull time/Y2038 updates from Thomas Gleixner: - Consolidate SySV IPC UAPI headers - Convert SySV IPC to the new COMPAT_32BIT_TIME mechanism - Cleanup the core interfaces and standardize on the ktime_get_* naming convention. - Convert the X86 platform ops to timespec64 - Remove the ugly temporary timespec64 hack * 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86: Convert x86_platform_ops to timespec64 timekeeping: Add more coarse clocktai/boottime interfaces timekeeping: Add ktime_get_coarse_with_offset timekeeping: Standardize on ktime_get_*() naming timekeeping: Clean up ktime_get_real_ts64 timekeeping: Remove timespec64 hack y2038: ipc: Redirect ipc(SEMTIMEDOP, ...) to compat_ksys_semtimedop y2038: ipc: Enable COMPAT_32BIT_TIME y2038: ipc: Use __kernel_timespec y2038: ipc: Report long times to user space y2038: ipc: Use ktime_get_real_seconds consistently y2038: xtensa: Extend sysvipc data structures y2038: powerpc: Extend sysvipc data structures y2038: sparc: Extend sysvipc data structures y2038: parisc: Extend sysvipc data structures y2038: mips: Extend sysvipc data structures y2038: arm64: Extend sysvipc compat data structures y2038: s390: Remove unneeded ipc uapi header files y2038: ia64: Remove unneeded ipc uapi header files y2038: alpha: Remove unneeded ipc uapi header files ...
| * | timekeeping: Add ktime_get_coarse_with_offsetArnd Bergmann2018-05-191-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I have run into a couple of drivers using current_kernel_time() suffering from the y2038 problem, and they could be converted to using ktime_t, but don't have interfaces that skip the nanosecond calculation at the moment. This introduces ktime_get_coarse_with_offset() as a simpler variant of ktime_get_with_offset(), and adds wrappers for the three time domains we support with the existing function. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-5-arnd@arndb.de
| * | timekeeping: Standardize on ktime_get_*() namingArnd Bergmann2018-05-191-14/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current_kernel_time64, get_monotonic_coarse64, getrawmonotonic64, get_monotonic_boottime64 and timekeeping_clocktai64 interfaces have rather inconsistent naming, and they differ in the calling conventions by passing the output either by reference or as a return value. Rename them to ktime_get_coarse_real_ts64, ktime_get_coarse_ts64, ktime_get_raw_ts64, ktime_get_boottime_ts64 and ktime_get_clocktai_ts64 respectively, and provide the interfaces with macros or inline functions as needed. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-4-arnd@arndb.de
| * | timekeeping: Clean up ktime_get_real_ts64Arnd Bergmann2018-05-191-25/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In a move to make ktime_get_*() the preferred driver interface into the timekeeping code, sanitizes ktime_get_real_ts64() to be a proper exported symbol rather than an alias for getnstimeofday64(). The internal __getnstimeofday64() is no longer used, so remove that and merge it into ktime_get_real_ts64(). Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-3-arnd@arndb.de
| * | timekeeping: Remove timespec64 hackArnd Bergmann2018-05-191-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At this point, we have converted most of the kernel to use timespec64 consistently in place of timespec, so it seems it's time to make timespec64 the native structure and define timespec in terms of that one on 64-bit architectures. Starting with gcc-5, the compiler can completely optimize away the timespec_to_timespec64 and timespec64_to_timespec functions on 64-bit architectures. With older compilers, we introduce a couple of extra copies of local variables, but those are easily avoided by using the timespec64 based interfaces consistently, as we do in most of the important code paths already. The main upside of removing the hack is that printing the tv_sec field of a timespec64 structure can now use the %lld format string on all architectures without a cast to time64_t. Without this patch, the field is a 'long' type and would have to be printed using %ld on 64-bit architectures. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: y2038@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180427134016.2525989-2-arnd@arndb.de
| * | Merge branch 'linus' into timers/2038Thomas Gleixner2018-05-1911-122/+126
| |\ \ | | | | | | | | | | | | Merge upstream to pick up changes on which pending patches depend on.
* | \ \ Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2018-06-058-52/+106
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timers and timekeeping updates from Thomas Gleixner: - Core infrastucture work for Y2038 to address the COMPAT interfaces: + Add a new Y2038 safe __kernel_timespec and use it in the core code + Introduce config switches which allow to control the various compat mechanisms + Use the new config switch in the posix timer code to control the 32bit compat syscall implementation. - Prevent bogus selection of CPU local clocksources which causes an endless reselection loop - Remove the extra kthread in the clocksource code which has no value and just adds another level of indirection - The usual bunch of trivial updates, cleanups and fixlets all over the place - More SPDX conversions * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) clocksource/drivers/mxs_timer: Switch to SPDX identifier clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier clocksource/drivers/timer-imx-gpt: Switch to SPDX identifier clocksource/drivers/timer-imx-gpt: Remove outdated file path clocksource/drivers/arc_timer: Add comments about locking while read GFRC clocksource/drivers/mips-gic-timer: Add pr_fmt and reword pr_* messages clocksource/drivers/sprd: Fix Kconfig dependency clocksource: Move inline keyword to the beginning of function declarations timer_list: Remove unused function pointer typedef timers: Adjust a kernel-doc comment tick: Prefer a lower rating device only if it's CPU local device clocksource: Remove kthread time: Change nanosleep to safe __kernel_* types time: Change types to new y2038 safe __kernel_* types time: Fix get_timespec64() for y2038 safe compat interfaces time: Add new y2038 safe __kernel_timespec posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME time: Introduce CONFIG_COMPAT_32BIT_TIME time: Introduce CONFIG_64BIT_TIME in architectures compat: Enable compat_get/put_timespec64 always ...
| * | | | clocksource: Move inline keyword to the beginning of function declarationsMathieu Malaterre2018-05-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The inline keyword was not at the beginning of the function declarations. Fix the following warnings triggered when using W=1: kernel/time/clocksource.c:456:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] kernel/time/clocksource.c:457:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180516195943.31924-1-malat@debian.org
| * | | | timer_list: Remove unused function pointer typedefChen Lin2018-05-131-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the 'printf_fn_t' typedef as it is not used. Signed-off-by: Chen Lin <chen45464546@163.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: sboyd@kernel.org Cc: john.stultz@linaro.org Link: https://lkml.kernel.org/r/1526053649-24229-1-git-send-email-chen45464546@163.com
| * | | | timers: Adjust a kernel-doc commentMauro Carvalho Chehab2018-05-131-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Those three warnings can easily solved by using :: to indicate a code block: ./kernel/time/timer.c:1259: WARNING: Unexpected indentation. ./kernel/time/timer.c:1261: WARNING: Unexpected indentation. ./kernel/time/timer.c:1262: WARNING: Block quote ends without a blank line; unexpected unindent. While here, align the lines at the block. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Linux Doc Mailing List <linux-doc@vger.kernel.org> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/f02e6a0ce27f3b5e33415d92d07a40598904b3ee.1525684985.git.mchehab%2Bsamsung@kernel.org
| * | | | tick: Prefer a lower rating device only if it's CPU local deviceSudeep Holla2018-05-131-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Checking the equality of cpumask for both new and old tick device doesn't ensure that it's CPU local device. This will cause issue if a low rating clockevent tick device is registered first followed by the registration of higher rating clockevent tick device. In such case, clockevents_released list will never get emptied as both the devices get selected as preferred one and we will loop forever in clockevents_notify_released. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: https://lkml.kernel.org/r/1525881728-4858-1-git-send-email-sudeep.holla@arm.com
| * | | | clocksource: Remove kthreadPeter Zijlstra2018-05-021-21/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The clocksource watchdog uses a work to spawn a kthread to run the watchdog. That is about as silly as it sounds, run the watchdog directly from the work. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20180430100344.713862818@infradead.org
| * | | | Merge branch 'timers/urgent' into timers/coreThomas Gleixner2018-05-0211-122/+126
| |\ \ \ \ | | |/ / / | |/| / / | | |/ / Pick up urgent fixes to apply dependent cleanup patch
| * | | time: Change nanosleep to safe __kernel_* typesDeepa Dinamani2018-04-193-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change over clock_nanosleep syscalls to use y2038 safe __kernel_timespec times. This will enable changing over of these syscalls to use new y2038 safe syscalls when the architectures define the CONFIG_64BIT_TIME. Note that nanosleep syscall is deprecated and does not have a plan for making it y2038 safe. But, the syscall should work as before on 64 bit machines and on 32 bit machines, the syscall works correctly until y2038 as before using the existing compat syscall version. There is no new syscall for supporting 64 bit time_t on 32 bit architectures. Cc: linux-api@vger.kernel.org Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | time: Change types to new y2038 safe __kernel_* typesDeepa Dinamani2018-04-192-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change over clock_settime, clock_gettime and clock_getres syscalls to use __kernel_timespec times. This will enable changing over of these syscalls to use new y2038 safe syscalls when the architectures define the CONFIG_64BIT_TIME. Cc: linux-api@vger.kernel.org Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | time: Fix get_timespec64() for y2038 safe compat interfacesDeepa Dinamani2018-04-191-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | get/put_timespec64() interfaces will eventually be used for conversions between the new y2038 safe struct __kernel_timespec and struct timespec64. The new y2038 safe syscalls have a common entry for native and compat interfaces. On compat interfaces, the high order bits of nanoseconds should be zeroed out. This is because the application code or the libc do not guarantee zeroing of these. If used without zeroing, kernel might be at risk of using timespec values incorrectly. Note that clearing of bits is dependent on CONFIG_64BIT_TIME for now. This is until COMPAT_USE_64BIT_TIME has been handled correctly. x86 will be the first architecture that will use the CONFIG_64BIT_TIME. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIMEDeepa Dinamani2018-04-193-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clock_gettime, clock_settime, clock_getres and clock_nanosleep compat syscalls are also repurposed to provide backward compatibility to support 32 bit time_t on 32 bit systems. Note that nanosleep compat syscall will also be treated the same way as the above syscalls as it shares common handler functions with clock_nanosleep. But, there is no plan to provide y2038 safe solution for nanosleep. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | | compat: Enable compat_get/put_timespec64 alwaysDeepa Dinamani2018-04-191-0/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These functions are used in the repurposed compat syscalls to provide backward compatibility for using 32 bit time_t on 32 bit systems. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | | | Merge branch 'hch.procfs' of ↵Linus Torvalds2018-06-041-14/+2
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull procfs updates from Al Viro: "Christoph's proc_create_... cleanups series" * 'hch.procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (44 commits) xfs, proc: hide unused xfs procfs helpers isdn/gigaset: add back gigaset_procinfo assignment proc: update SIZEOF_PDE_INLINE_NAME for the new pde fields tty: replace ->proc_fops with ->proc_show ide: replace ->proc_fops with ->proc_show ide: remove ide_driver_proc_write isdn: replace ->proc_fops with ->proc_show atm: switch to proc_create_seq_private atm: simplify procfs code bluetooth: switch to proc_create_seq_data netfilter/x_tables: switch to proc_create_seq_private netfilter/xt_hashlimit: switch to proc_create_{seq,single}_data neigh: switch to proc_create_seq_data hostap: switch to proc_create_{seq,single}_data bonding: switch to proc_create_seq_data rtc/proc: switch to proc_create_single_data drbd: switch to proc_create_single resource: switch to proc_create_seq_data staging/rtl8192u: simplify procfs code jfs: simplify procfs code ...
| * | | proc: introduce proc_create_seq_privateChristoph Hellwig2018-05-161-14/+2
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | Variant of proc_create_data that directly take a struct seq_operations argument + a private state size and drastically reduces the boilerplate code in the callers. All trivial callers converted over. Signed-off-by: Christoph Hellwig <hch@lst.de>
* / | tick/broadcast: Use for_each_cpu() specially on UP kernelsDexuan Cui2018-05-151-0/+8
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | for_each_cpu() unintuitively reports CPU0 as set independent of the actual cpumask content on UP kernels. This causes an unexpected PIT interrupt storm on a UP kernel running in an SMP virtual machine on Hyper-V, and as a result, the virtual machine can suffer from a strange random delay of 1~20 minutes during boot-up, and sometimes it can hang forever. Protect if by checking whether the cpumask is empty before entering the for_each_cpu() loop. [ tglx: Use !IS_ENABLED(CONFIG_SMP) instead of #ifdeffery ] Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Josh Poulson <jopoulso@microsoft.com> Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: stable@vger.kernel.org Cc: Rakib Mullick <rakib.mullick@gmail.com> Cc: Jork Loeser <Jork.Loeser@microsoft.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: KY Srinivasan <kys@microsoft.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Link: https://lkml.kernel.org/r/KL1P15301MB000678289FE55BA365B3279ABF990@KL1P15301MB0006.APCP153.PROD.OUTLOOK.COM Link: https://lkml.kernel.org/r/KL1P15301MB0006FA63BC22BEB64902EAA0BF930@KL1P15301MB0006.APCP153.PROD.OUTLOOK.COM
* | clocksource: Rework stale commentPeter Zijlstra2018-05-021-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | AFAICS the hotplug code no longer uses this function. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20180430100344.656525644@infradead.org
* | clocksource: Consistent de-rate when marking unstablePeter Zijlstra2018-05-021-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a registered clocksource gets marked unstable the watchdog_kthread will de-rate and re-select the clocksource. Ensure it also de-rates when getting called on an unregistered clocksource. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180430100344.594904898@infradead.org
* | clocksource: Initialize cs->wd_listPeter Zijlstra2018-05-021-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A number of places relies on list_empty(&cs->wd_list), however the list_head does not get initialized. Do so upon registration, such that thereafter it is possible to rely on list_empty() correctly reflecting the list membership status. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Diego Viola <diego.viola@gmail.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable@vger.kernel.org Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20180430100344.472662715@infradead.org
* | clocksource: Allow clocksource_mark_unstable() on unregistered clocksourcesPeter Zijlstra2018-05-021-16/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because of how the code flips between tsc-early and tsc clocksources it might need to mark one or both unstable. The current code in mark_tsc_unstable() only worked because previously it registered the tsc clocksource once and then never touched it. Since it now unregisters the tsc-early clocksource, it needs to know if a clocksource got unregistered and the current cs->mult test doesn't work for that. Instead use list_empty(&cs->list) to test for registration. Furthermore, since clocksource_mark_unstable() needs to place the cs on the wd_list, it links the cs->list and cs->wd_list serialization. It must not see a clocsource registered (!empty cs->list) but already past dequeue_watchdog(). So place {en,de}queue{,_watchdog}() under the same lock. Provided cs->list is initialized to empty, this then allows us to unconditionally use clocksource_mark_unstable(), regardless of the registration state. Fixes: aa83c45762a2 ("x86/tsc: Introduce early tsc clocksource") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Diego Viola <diego.viola@gmail.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180502135312.GS12217@hirez.programming.kicks-ass.net
* | Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIMEThomas Gleixner2018-04-268-84/+69
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert commits 92af4dcb4e1c ("tracing: Unify the "boot" and "mono" tracing clocks") 127bfa5f4342 ("hrtimer: Unify MONOTONIC and BOOTTIME clock behavior") 7250a4047aa6 ("posix-timers: Unify MONOTONIC and BOOTTIME clock behavior") d6c7270e913d ("timekeeping: Remove boot time specific code") f2d6fdbfd238 ("Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior") d6ed449afdb3 ("timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock") 72199320d49d ("timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock") As stated in the pull request for the unification of CLOCK_MONOTONIC and CLOCK_BOOTTIME, it was clear that we might have to revert the change. As reported by several folks systemd and other applications rely on the documented behaviour of CLOCK_MONOTONIC on Linux and break with the above changes. After resume daemons time out and other timeout related issues are observed. Rafael compiled this list: * systemd kills daemons on resume, after >WatchdogSec seconds of suspending (Genki Sky). [Verified that that's because systemd uses CLOCK_MONOTONIC and expects it to not include the suspend time.] * systemd-journald misbehaves after resume: systemd-journald[7266]: File /var/log/journal/016627c3c4784cd4812d4b7e96a34226/system.journal corrupted or uncleanly shut down, renaming and replacing. (Mike Galbraith). * NetworkManager reports "networking disabled" and networking is broken after resume 50% of the time (Pavel). [May be because of systemd.] * MATE desktop dims the display and starts the screensaver right after system resume (Pavel). * Full system hang during resume (me). [May be due to systemd or NM or both.] That happens on debian and open suse systems. It's sad, that these problems were neither catched in -next nor by those folks who expressed interest in this change. Reported-by: Rafael J. Wysocki <rjw@rjwysocki.net> Reported-by: Genki Sky <sky@genki.is>, Reported-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Easton <kevin@guarana.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Salyzyn <salyzyn@android.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org>
* | tick/sched: Do not mess with an enqueued hrtimerThomas Gleixner2018-04-261-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kaike reported that in tests rdma hrtimers occasionaly stopped working. He did great debugging, which provided enough context to decode the problem. CPU 3 CPU 2 idle start sched_timer expires = 712171000000 queue->next = sched_timer start rdmavt timer. expires = 712172915662 lock(baseof(CPU3)) tick_nohz_stop_tick() tick = 716767000000 timerqueue_add(tmr) hrtimer_set_expires(sched_timer, tick); sched_timer->expires = 716767000000 <---- FAIL if (tmr->expires < queue->next->expires) hrtimer_start(sched_timer) queue->next = tmr; lock(baseof(CPU3)) unlock(baseof(CPU3)) timerqueue_remove() timerqueue_add() ts->sched_timer is queued and queue->next is pointing to it, but then ts->sched_timer.expires is modified. This not only corrupts the ordering of the timerqueue RB tree, it also makes CPU2 see the new expiry time of timerqueue->next->expires when checking whether timerqueue->next needs to be updated. So CPU2 sees that the rdma timer is earlier than timerqueue->next and sets the rdma timer as new next. Depending on whether it had also seen the new time at RB tree enqueue, it might have queued the rdma timer at the wrong place and then after removing the sched_timer the RB tree is completely hosed. The problem was introduced with a commit which tried to solve inconsistency between the hrtimer in the tick_sched data and the underlying hardware clockevent. It split out hrtimer_set_expires() to store the new tick time in both the NOHZ and the NOHZ + HIGHRES case, but missed the fact that in the NOHZ + HIGHRES case the hrtimer might still be queued. Use hrtimer_start(timer, tick...) for the NOHZ + HIGHRES case which sets timer->expires after canceling the timer and move the hrtimer_set_expires() invocation into the NOHZ only code path which is not affected as it merily uses the hrtimer as next event storage so code pathes can be shared with the NOHZ + HIGHRES case. Fixes: d4af6d933ccf ("nohz: Fix spurious warning when hrtimer and clockevent get out of sync") Reported-by: "Wan Kaike" <kaike.wan@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Frederic Weisbecker <frederic@kernel.org> Cc: "Marciniszyn Mike" <mike.marciniszyn@intel.com> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: linux-rdma@vger.kernel.org Cc: "Dalessandro Dennis" <dennis.dalessandro@intel.com> Cc: "Fleck John" <john.fleck@intel.com> Cc: stable@vger.kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: "Weiny Ira" <ira.weiny@intel.com> Cc: "linux-rdma@vger.kernel.org" Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1804241637390.1679@nanos.tec.linutronix.de Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1804242119210.1597@nanos.tec.linutronix.de
* | posix-cpu-timers: Ensure set_process_cpu_timer is always evaluatedLaura Abbott2018-04-191-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit a9445e47d897 ("posix-cpu-timers: Make set_process_cpu_timer() more robust") moved the check into the 'if' statement. Unfortunately, it did so on the right side of an && which means that it may get short circuited and never evaluated. This is easily reproduced with: $ cat loop.c void main() { struct rlimit res; /* set the CPU time limit */ getrlimit(RLIMIT_CPU,&res); res.rlim_cur = 2; res.rlim_max = 2; setrlimit(RLIMIT_CPU,&res); while (1); } Which will hang forever instead of being killed. Fix this by pulling the evaluation out of the if statement but checking the return value instead. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1568337 Fixes: a9445e47d897 ("posix-cpu-timers: Make set_process_cpu_timer() more robust") Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Cc: "Max R . P . Grossmann" <m@max.pm> Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180417215742.2521-1-labbott@redhat.com
* | timekeeping: Remove __current_kernel_time()Baolin Wang2018-04-171-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __current_kernel_time() function based on 'struct timespec' is no longer recommended for new code, and the only user of this function has been replaced by commit 6909e29fdefb ("kdb: use __ktime_get_real_seconds instead of __current_kernel_time"). Remove the obsolete interface. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: sboyd@kernel.org Cc: broonie@kernel.org Cc: john.stultz@linaro.org Link: https://lkml.kernel.org/r/1a9dbea7ee2cda7efe9ed330874075cf17fdbff6.1523596316.git.baolin.wang@linaro.org
* | clockevents: Fix kernel messages split across multiple linesGeert Uytterhoeven2018-04-171-6/+5
|/ | | | | | | | | | | | | | Convert the clockevents driver from old-style printk() to pr_info() and pr_cont(), to fix split kernel messages like below: Clockevents: could not switch to one-shot mode: dummy_timer is not functional. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: https://lkml.kernel.org/r/1522942018-14471-1-git-send-email-geert%2Brenesas@glider.be
* Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2018-04-161-0/+10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of fixes and updates for x86: - Address a swiotlb regression which was caused by the recent DMA rework and made driver fail because dma_direct_supported() returned false - Fix a signedness bug in the APIC ID validation which caused invalid APIC IDs to be detected as valid thereby bloating the CPU possible space. - Fix inconsisten config dependcy/select magic for the MFD_CS5535 driver. - Fix a corruption of the physical address space bits when encryption has reduced the address space and late cpuinfo updates overwrite the reduced bit information with the original value. - Dominiks syscall rework which consolidates the architecture specific syscall functions so all syscalls can be wrapped with the same macros. This allows to switch x86/64 to struct pt_regs based syscalls. Extend the clearing of user space controlled registers in the entry patch to the lower registers" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Fix signedness bug in APIC ID validity checks x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption x86/olpc: Fix inconsistent MFD_CS5535 configuration swiotlb: Use dma_direct_supported() for swiotlb_ops syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*() syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention syscalls/core, syscalls/x86: Clean up syscall stub naming convention syscalls/x86: Extend register clearing on syscall entry to lower registers syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64 syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32 syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y x86/syscalls: Don't pointlessly reload the system call number x86/mm: Fix documentation of module mapping range with 4-level paging x86/cpuid: Switch to 'static const' specifier
| * syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscallsDominik Brodowski2018-04-051-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It may be useful for an architecture to override the definitions of the COMPAT_SYSCALL_DEFINE0() and __COMPAT_SYSCALL_DEFINEx() macros in <linux/compat.h>, in particular to use a different calling convention for syscalls. This patch provides a mechanism to do so, based on the previously introduced CONFIG_ARCH_HAS_SYSCALL_WRAPPER. If it is enabled, <asm/sycall_wrapper.h> is included in <linux/compat.h> and may be used to define the macros mentioned above. Moreover, as the syscall calling convention may be different if CONFIG_ARCH_HAS_SYSCALL_WRAPPER is set, the compat syscall function prototypes in <linux/compat.h> are #ifndef'd out in that case. As some of the syscalls and/or compat syscalls may not be present, the COND_SYSCALL() and COND_SYSCALL_COMPAT() macros in kernel/sys_ni.c as well as the SYS_NI() and COMPAT_SYS_NI() macros in kernel/time/posix-stubs.c can be re-defined in <asm/syscall_wrapper.h> iff CONFIG_ARCH_HAS_SYSCALL_WRAPPER is enabled. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180405095307.3730-5-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge tag 'for_linus-4.16' of ↵Linus Torvalds2018-04-121-2/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull kdb updates from Jason Wessel: - fix 2032 time access issues and new compiler warnings - minor regression test cleanup - formatting fixes for end user use of kdb * tag 'for_linus-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: kdb: use memmove instead of overlapping memcpy kdb: use ktime_get_mono_fast_ns() instead of ktime_get_ts() kdb: bl: don't use tab character in output kdb: drop newline in unknown command output kdb: make "mdr" command repeat kdb: use __ktime_get_real_seconds instead of __current_kernel_time misc: kgdbts: Display progress of asynchronous tests
| * | kdb: use __ktime_get_real_seconds instead of __current_kernel_timeArnd Bergmann2018-01-251-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kdb is the only user of the __current_kernel_time() interface, which is not y2038 safe and should be removed at some point. The kdb code also goes to great lengths to print the time in a human-readable format from 'struct timespec', again using a non-y2038-safe re-implementation of the generic time_to_tm() code. Using __current_kernel_time() here is necessary since the regular accessors that require a sequence lock might hang when called during the xtime update. However, this is safe in the particular case since kdb is only interested in the tv_sec field that is updated atomically. In order to make this y2038-safe, I'm converting the code to the generic time64_to_tm helper, but that introduces the problem that we have no interface like __current_kernel_time() that provides a 64-bit timestamp in a lockless, safe and architecture-independent way. I have multiple ideas for how to solve that: - __ktime_get_real_seconds() is lockless, but can return incorrect results on 32-bit architectures in the special case that we are in the process of changing the time across the epoch, either during the timer tick that overflows the seconds in 2038, or while calling settimeofday. - ktime_get_real_fast_ns() would work in this context, but does require a call into the clocksource driver to return a high-resolution timestamp. This may have undesired side-effects in the debugger, since we want to limit the interactions with the rest of the kernel. - Adding a ktime_get_real_fast_seconds() based on tk_fast_mono plus tkr->base_real without the tk_clock_read() delta. Not sure about the value of adding yet another interface here. - Changing the existing ktime_get_real_seconds() to use tk_fast_mono on 32-bit architectures rather than xtime_sec. I think this could work, but am not entirely sure if this is an improvement. I picked the first of those for simplicity here. It's technically not correct but probably good enough as the time is only used for the debugging output and the race will likely never be hit in practice. Another downside is having to move the declaration into a public header file. Let me know if anyone has a different preference. Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://patchwork.kernel.org/patch/9775309/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
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*-. \ \ Merge branches 'pm-cpuidle' and 'pm-qos'Rafael J. Wysocki2018-04-114-82/+241
|\ \ \ \ | | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * pm-cpuidle: tick-sched: avoid a maybe-uninitialized warning cpuidle: Add definition of residency to sysfs documentation time: hrtimer: Use timerqueue_iterate_next() to get to the next timer nohz: Avoid duplication of code related to got_idle_tick nohz: Gather tick_sched booleans under a common flag field cpuidle: menu: Avoid selecting shallow states with stopped tick cpuidle: menu: Refine idle state selection for running tick sched: idle: Select idle state before stopping the tick time: hrtimer: Introduce hrtimer_next_event_without() time: tick-sched: Split tick_nohz_stop_sched_tick() cpuidle: Return nohz hint from cpuidle_select() jiffies: Introduce USER_TICK_USEC and redefine TICK_USEC sched: idle: Do not stop the tick before cpuidle_idle_call() sched: idle: Do not stop the tick upfront in the idle loop time: tick-sched: Reorganize idle tick management code * pm-qos: PM / QoS: mark expected switch fall-throughs
| * | | tick-sched: avoid a maybe-uninitialized warningArnd Bergmann2018-04-101-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The use of bitfields seems to confuse gcc, leading to a false-positive warning in all compiler versions: kernel/time/tick-sched.c: In function 'tick_nohz_idle_exit': kernel/time/tick-sched.c:538:2: error: 'now' may be used uninitialized in this function [-Werror=maybe-uninitialized] This introduces a temporary variable to track the flags so gcc doesn't have to evaluate twice, eliminating the code path that leads to the warning. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85301 Fixes: 1cae544d42d2 ("nohz: Gather tick_sched booleans under a common flag field") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * | | time: hrtimer: Use timerqueue_iterate_next() to get to the next timerRafael J. Wysocki2018-04-091-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use timerqueue_iterate_next() to get to the next timer in __hrtimer_next_event_base() without browsing the timerqueue details diredctly. No intentional changes in functionality. Suggested-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * | | nohz: Avoid duplication of code related to got_idle_tickRafael J. Wysocki2018-04-091-10/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the code setting ts->got_idle_tick into tick_sched_do_timer() to avoid code duplication. No intentional changes in functionality. Suggested-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
| * | | nohz: Gather tick_sched booleans under a common flag fieldFrederic Weisbecker2018-04-092-9/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Optimize the space and leave plenty of room for further flags. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> [ rjw: Do not use __this_cpu_read() to access tick_stopped and add got_idle_tick to avoid overloading inidle ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * | | cpuidle: menu: Refine idle state selection for running tickRafael J. Wysocki2018-04-091-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the tick isn't stopped, the target residency of the state selected by the menu governor may be greater than the actual time to the next tick and that means lost energy. To avoid that, make tick_nohz_get_sleep_length() return the current time to the next event (before stopping the tick) in addition to the estimated one via an extra pointer argument and make menu_select() use that value to refine the state selection when necessary. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * | | sched: idle: Select idle state before stopping the tickRafael J. Wysocki2018-04-092-14/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to address the issue with short idle duration predictions by the idle governor after the scheduler tick has been stopped, reorder the code in cpuidle_idle_call() so that the governor idle state selection runs before tick_nohz_idle_go_idle() and use the "nohz" hint returned by cpuidle_select() to decide whether or not to stop the tick. This isn't straightforward, because menu_select() invokes tick_nohz_get_sleep_length() to get the time to the next timer event and the number returned by the latter comes from __tick_nohz_idle_stop_tick(). Fortunately, however, it is possible to compute that number without actually stopping the tick and with the help of the existing code. Namely, tick_nohz_get_sleep_length() can be made call tick_nohz_next_event(), introduced earlier, to get the time to the next non-highres timer event. If that happens, tick_nohz_next_event() need not be called by __tick_nohz_idle_stop_tick() again. If it turns out that the scheduler tick cannot be stopped going forward or the next timer event is too close for the tick to be stopped, tick_nohz_get_sleep_length() can simply return the time to the next event currently programmed into the corresponding clock event device. In addition to knowing the return value of tick_nohz_next_event(), however, tick_nohz_get_sleep_length() needs to know the time to the next highres timer event, but with the scheduler tick timer excluded, which can be computed with the help of hrtimer_get_next_event(). That minimum of that number and the tick_nohz_next_event() return value is the total time to the next timer event with the assumption that the tick will be stopped. It can be returned to the idle governor which can use it for predicting idle duration (under the assumption that the tick will be stopped) and deciding whether or not it makes sense to stop the tick before putting the CPU into the selected idle state. With the above, the sleep_length field in struct tick_sched is not necessary any more, so drop it. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199227 Reported-by: Doug Smythies <dsmythies@telus.net> Reported-by: Thomas Ilsche <thomas.ilsche@tu-dresden.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
| * | | time: hrtimer: Introduce hrtimer_next_event_without()Rafael J. Wysocki2018-04-071-2/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The next set of changes will need to compute the time to the next hrtimer event over all hrtimers except for the scheduler tick one. To that end introduce a new helper function, hrtimer_next_event_without(), for computing the time until the next hrtimer event over all timers except for one and modify the underlying code in __hrtimer_next_event_base() to prepare it for being called by that new function. No intentional changes in functionality. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
| * | | time: tick-sched: Split tick_nohz_stop_sched_tick()Rafael J. Wysocki2018-04-072-46/+82
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to address the issue with short idle duration predictions by the idle governor after the scheduler tick has been stopped, split tick_nohz_stop_sched_tick() into two separate routines, one computing the time to the next timer event and the other simply stopping the tick when the time to the next timer event is known. Prepare these two routines to be called separately, as one of them will be called by the idle governor in the cpuidle_select() code path after subsequent changes. Update the former callers of tick_nohz_stop_sched_tick() to use the new routines, tick_nohz_next_event() and tick_nohz_stop_tick(), instead of it and move the updates of the sleep_length field in struct tick_sched into __tick_nohz_idle_stop_tick() as it doesn't need to be updated anywhere else. There should be no intentional visible changes in functionality resulting from this change. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
| * | | cpuidle: Return nohz hint from cpuidle_select()Rafael J. Wysocki2018-04-061-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new pointer argument to cpuidle_select() and to the ->select cpuidle governor callback to allow a boolean value indicating whether or not the tick should be stopped before entering the selected state to be returned from there. Make the ladder governor ignore that pointer (to preserve its current behavior) and make the menu governor return 'false" through it if: (1) the idle exit latency is constrained at 0, or (2) the selected state is a polling one, or (3) the expected idle period duration is within the tick period range. In addition to that, the correction factor computations in the menu governor need to take the possibility that the tick may not be stopped into account to avoid artificially small correction factor values. To that end, add a mechanism to record tick wakeups, as suggested by Peter Zijlstra, and use it to modify the menu_update() behavior when tick wakeup occurs. Namely, if the CPU is woken up by the tick and the return value of tick_nohz_get_sleep_length() is not within the tick boundary, the predicted idle duration is likely too short, so make menu_update() try to compensate for that by updating the governor statistics as though the CPU was idle for a long time. Since the value returned through the new argument pointer of cpuidle_select() is not used by its caller yet, this change by itself is not expected to alter the functionality of the code. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * | | jiffies: Introduce USER_TICK_USEC and redefine TICK_USECRafael J. Wysocki2018-04-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the subsequent changes will need a TICK_USEC definition analogous to TICK_NSEC, rename the existing TICK_USEC as USER_TICK_USEC, update its users and redefine TICK_USEC accordingly. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>