kernel.git/arch/x86/kernel/tsc.c, branch linux-5.6.y

x86/tsc: Respect tsc command line paraemeter for clocksource_tsc_early

2019-11-05T00:24:56Z

The introduction of clocksource_tsc_early broke the functionality of "tsc=reliable" and "tsc=nowatchdog" command line parameters, since clocksource_tsc_early is unconditionally registered with CLOCK_SOURCE_MUST_VERIFY and thus put on the watchdog list. This can cause the TSC to be declared unstable during boot: clocksource: timekeeping watchdog on CPU0: Marking clocksource 'tsc-early' as unstable because the skew is too large: clocksource: 'refined-jiffies' wd_now: fffb7018 wd_last: fffb6e9d mask: ffffffff clocksource: 'tsc-early' cs_now: 68a6a7070f6a0 cs_last: 68a69ab6f74d6 mask: ffffffffffffffff tsc: Marking TSC unstable due to clocksource watchdog The corresponding elapsed times are cs_nsec=1224152026 and wd_nsec=378942392, so the watchdog differs from TSC by 0.84 seconds. This happens when HPET is not available and jiffies are used as the TSC watchdog instead and the jiffies update is not happening due to lost timer interrupts in periodic mode, which can happen e.g. with expensive debug mechanisms enabled or under massive overload conditions in virtualized environments. Before the introduction of the early TSC clocksource the command line parameters "tsc=reliable" and "tsc=nowatchdog" could be used to work around this issue. Restore the behaviour by disabling the watchdog if requested on the kernel command line. [ tglx: Clarify changelog ] Fixes: aa83c45762a24 ("x86/tsc: Introduce early tsc clocksource") Signed-off-by: Michael Zhivich Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20191024175945.14338-1-mzhivich@akamai.com

x86/intel: Aggregate microserver naming

2019-08-28T09:29:32Z

Currently big microservers have _XEON_D while small microservers have _X, Make it uniformly: _D. for i in `git grep -l "$INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6$.*_$X\|XEON_D$"` do sed -i -e 's/$\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6$.*ATOM.*\)_X/\1_D/g' \ -e 's/$\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6$.*\)_XEON_D/\1_D/g' ${i} done Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Tony Luck Cc: x86@kernel.org Cc: Dave Hansen Cc: Thomas Gleixner Cc: Borislav Petkov Link: https://lkml.kernel.org/r/20190827195122.677152989@infradead.org

Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2019-07-09T00:27:24Z

Pull x86 cleanups from Ingo Molnar: "Misc small cleanups: removal of superfluous code and coding style cleanups mostly" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kexec: Make variable static and config dependent x86/defconfigs: Remove useless UEVENT_HELPER_PATH x86/amd_nb: Make hygon_nb_misc_ids static x86/tsc: Move inline keyword to the beginning of function declarations x86/io_delay: Define IO_DELAY macros in C instead of Kconfig x86/io_delay: Break instead of fallthrough in switch statement

Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2019-07-08T18:22:57Z

Pull x96 apic updates from Thomas Gleixner: "Updates for the x86 APIC interrupt handling and APIC timer: - Fix a long standing issue with spurious interrupts which was caused by the big vector management rework a few years ago. Robert Hodaszi provided finally enough debug data and an excellent initial failure analysis which allowed to understand the underlying issues. This contains a change to the core interrupt management code which is required to handle this correctly for the APIC/IO_APIC. The core changes are NOOPs for most architectures except ARM64. ARM64 is not impacted by the change as confirmed by Marc Zyngier. - Newer systems allow to disable the PIT clock for power saving causing panic in the timer interrupt delivery check of the IO/APIC when the HPET timer is not enabled either. While the clock could be turned on this would cause an endless whack a mole game to chase the proper register in each affected chipset. These systems provide the relevant frequencies for TSC, CPU and the local APIC timer via CPUID and/or MSRs, which allows to avoid the PIT/HPET based calibration. As the calibration code is the only usage of the legacy timers on modern systems and is skipped anyway when the frequencies are known already, there is no point in setting up the PIT and actually checking for the interrupt delivery via IO/APIC. To achieve this on a wide variety of platforms, the CPUID/MSR based frequency readout has been made more robust, which also allowed to remove quite some workarounds which turned out to be not longer required. Thanks to Daniel Drake for analysis, patches and verification" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Seperate unused system vectors from spurious entry again x86/irq: Handle spurious interrupt after shutdown gracefully x86/ioapic: Implement irq_get_irqchip_state() callback genirq: Add optional hardware synchronization for shutdown genirq: Fix misleading synchronize_irq() documentation genirq: Delay deactivation in free_irq() x86/timer: Skip PIT initialization on modern chipsets x86/apic: Use non-atomic operations when possible x86/apic: Make apic_bsp_setup() static x86/tsc: Set LAPIC timer period to crystal clock frequency x86/apic: Rename 'lapic_timer_frequency' to 'lapic_timer_period' x86/tsc: Use CPUID.0x16 to calculate missing crystal frequency

x86/tsc: Move inline keyword to the beginning of function declarations

2019-06-14T15:02:09Z

The inline keyword was not at the beginning of the function declarations. Fix the following warnings triggered when using W=1: arch/x86/kernel/tsc.c:62:1: warning: 'inline' is not at beginning of declaration [-Wold-style-declaration] arch/x86/kernel/tsc.c:79:1: warning: 'inline' is not at beginning of declaration [-Wold-style-declaration] Signed-off-by: Mathieu Malaterre Signed-off-by: Thomas Gleixner Cc: trivial@kernel.org Cc: kernel-janitors@vger.kernel.org Cc: Peter Zijlstra Cc: Borislav Petkov Cc: "H. Peter Anvin" Link: https://lkml.kernel.org/r/20190524103252.28575-1-malat@debian.org

treewide: Add SPDX license identifier for missed files

2019-05-21T08:50:45Z

Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

cpufreq: Call transition notifier only once for each policy

2019-05-10T10:20:36Z

Currently, the notifiers are called once for each CPU of the policy->cpus cpumask. It would be more optimal if the notifier can be called only once and all the relevant information be provided to it. Out of the 23 drivers that register for the transition notifiers today, only 4 of them do per-cpu updates and the callback for the rest can be called only once for the policy without any impact. This would also avoid multiple function calls to the notifier callbacks and reduce multiple iterations of notifier core's code (which does locking as well). This patch adds pointer to the cpufreq policy to the struct cpufreq_freqs, so the notifier callback has all the information available to it with a single call. The five drivers which perform per-cpu updates are updated to use the cpufreq policy. The freqs->cpu field is redundant now and is removed. Acked-by: David S. Miller (sparc) Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

x86/tsc: Set LAPIC timer period to crystal clock frequency

2019-05-09T09:06:49Z

The APIC timer calibration (calibrate_APIC_timer()) can be skipped in cases where we know the APIC timer frequency. On Intel SoCs, we believe that the APIC is fed by the crystal clock; this would make sense, and the crystal clock frequency has been verified against the APIC timer calibration result on ApolloLake, GeminiLake, Kabylake, CoffeeLake, WhiskeyLake and AmberLake. Set lapic_timer_period based on the crystal clock frequency accordingly. APIC timer calibration would normally be skipped on modern CPUs by nature of the TSC deadline timer being used instead, however this change is still potentially useful, e.g. if the TSC deadline timer has been disabled with a kernel parameter. calibrate_APIC_timer() uses the legacy timer, but we are seeing new platforms that omit such legacy functionality, so avoiding such codepaths is becoming more important. Suggested-by: Thomas Gleixner Signed-off-by: Daniel Drake Reviewed-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: len.brown@intel.com Cc: linux@endlessm.com Cc: rafael.j.wysocki@intel.com Link: http://lkml.kernel.org/r/20190509055417.13152-3-drake@endlessm.com Link: https://lkml.kernel.org/r/20190419083533.32388-1-drake@endlessm.com Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1904031206440.1967@nanos.tec.linutronix.de Signed-off-by: Ingo Molnar

x86/tsc: Use CPUID.0x16 to calculate missing crystal frequency

2019-05-09T09:06:48Z

native_calibrate_tsc() had a data mapping Intel CPU families and crystal clock speed, but hardcoded tables are not ideal, and this approach was already problematic at least in the Skylake X case, as seen in commit: b51120309348 ("x86/tsc: Fix erroneous TSC rate on Skylake Xeon") By examining CPUID data from http://instlatx64.atw.hu/ and units in the lab, we have found that 3 different scenarios need to be dealt with, and we can eliminate most of the hardcoded data using an approach a little more advanced than before: 1. ApolloLake, GeminiLake, CannonLake (and presumably all new chipsets from this point) report the crystal frequency directly via CPUID.0x15. That's definitive data that we can rely upon. 2. Skylake, Kabylake and all variants of those two chipsets report a crystal frequency of zero, however we can calculate the crystal clock speed by condidering data from CPUID.0x16. This method correctly distinguishes between the two crystal clock frequencies present on different Skylake X variants that caused headaches before. As the calculations do not quite match the previously-hardcoded values in some cases (e.g. 23913043Hz instead of 24MHz), TSC refinement is enabled on all platforms where we had to calculate the crystal frequency in this way. 3. Denverton (GOLDMONT_X) reports a crystal frequency of zero and does not support CPUID.0x16, so we leave this entry hardcoded. Suggested-by: Thomas Gleixner Signed-off-by: Daniel Drake Reviewed-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: len.brown@intel.com Cc: linux@endlessm.com Cc: rafael.j.wysocki@intel.com Link: http://lkml.kernel.org/r/20190509055417.13152-1-drake@endlessm.com Link: https://lkml.kernel.org/r/20190419083533.32388-1-drake@endlessm.com Signed-off-by: Ingo Molnar

Merge tag 'pm-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2019-05-07T02:40:31Z

Pull power management updates from Rafael Wysocki: "These fix the (Intel-specific) Performance and Energy Bias Hint (EPB) handling and expose it to user space via sysfs, fix and clean up several cpufreq drivers, add support for two new chips to the qoriq cpufreq driver, fix, simplify and clean up the cpufreq core and the schedutil governor, add support for "CPU" domains to the generic power domains (genpd) framework and provide low-level PSCI firmware support for that feature, fix the exynos cpuidle driver and fix a couple of issues in the devfreq subsystem and clean it up. Specifics: - Fix the handling of Performance and Energy Bias Hint (EPB) on Intel processors and expose it to user space via sysfs to avoid having to access it through the generic MSR I/F (Rafael Wysocki). - Improve the handling of global turbo changes made by the platform firmware in the intel_pstate driver (Rafael Wysocki). - Convert some slow-path static_cpu_has() callers to boot_cpu_has() in cpufreq (Borislav Petkov). - Fix the frequency calculation loop in the armada-37xx cpufreq driver (Gregory CLEMENT). - Fix possible object reference leaks in multuple cpufreq drivers (Wen Yang). - Fix kerneldoc comment in the centrino cpufreq driver (dongjian). - Clean up the ACPI and maple cpufreq drivers (Viresh Kumar, Mohan Kumar). - Add support for lx2160a and ls1028a to the qoriq cpufreq driver (Vabhav Sharma, Yuantian Tang). - Fix kobject memory leak in the cpufreq core (Viresh Kumar). - Simplify the IOwait boosting in the schedutil cpufreq governor and rework the TSC cpufreq notifier on x86 (Rafael Wysocki). - Clean up the cpufreq core and statistics code (Yue Hu, Kyle Lin). - Improve the cpufreq documentation, add SPDX license tags to some PM documentation files and unify copyright notices in them (Rafael Wysocki). - Add support for "CPU" domains to the generic power domains (genpd) framework and provide low-level PSCI firmware support for that feature (Ulf Hansson). - Rearrange the PSCI firmware support code and add support for SYSTEM_RESET2 to it (Ulf Hansson, Sudeep Holla). - Improve genpd support for devices in multiple power domains (Ulf Hansson). - Unify target residency for the AFTR and coupled AFTR states in the exynos cpuidle driver (Marek Szyprowski). - Introduce new helper routine in the operating performance points (OPP) framework (Andrew-sh.Cheng). - Add support for passing on-die termination (ODT) and auto power down parameters from the kernel to Trusted Firmware-A (TF-A) to the rk3399_dmc devfreq driver (Enric Balletbo i Serra). - Add tracing to devfreq (Lukasz Luba). - Make the exynos-bus devfreq driver suspend all devices on system shutdown (Marek Szyprowski). - Fix a few minor issues in the devfreq subsystem and clean it up somewhat (Enric Balletbo i Serra, MyungJoo Ham, Rob Herring, Saravana Kannan, Yangtao Li). - Improve system wakeup diagnostics (Stephen Boyd). - Rework filesystem sync messages emitted during system suspend and hibernation (Harry Pan)" * tag 'pm-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (72 commits) cpufreq: Fix kobject memleak cpufreq: armada-37xx: fix frequency calculation for opp cpufreq: centrino: Fix centrino_setpolicy() kerneldoc comment cpufreq: qoriq: add support for lx2160a x86: tsc: Rework time_cpufreq_notifier() PM / Domains: Allow to attach a CPU via genpd_dev_pm_attach_by_id|name() PM / Domains: Search for the CPU device outside the genpd lock PM / Domains: Drop unused in-parameter to some genpd functions PM / Domains: Use the base device for driver_deferred_probe_check_state() cpufreq: qoriq: Add ls1028a chip support PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain PM / Domains: Allow OF lookup for multi PM domain case from ->attach_dev() PM / Domains: Don't kfree() the virtual device in the error path cpufreq: Move ->get callback check outside of __cpufreq_get() PM / Domains: remove unnecessary unlikely() cpufreq: Remove needless bios_limit check in show_bios_limit() drivers/cpufreq/acpi-cpufreq.c: This fixes the following checkpatch warning firmware/psci: add support for SYSTEM_RESET2 PM / devfreq: add tracing for scheduling work trace: events: add devfreq trace event file ...