linux/kernel/cpu.c, branch v5.7

Merge tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-03-31T01:06:39Z

Pull core SMP updates from Thomas Gleixner: "CPU (hotplug) updates: - Support for locked CSD objects in smp_call_function_single_async() which allows to simplify callsites in the scheduler core and MIPS - Treewide consolidation of CPU hotplug functions which ensures the consistency between the sysfs interface and kernel state. The low level functions cpu_up/down() are now confined to the core code and not longer accessible from random code" * tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) cpu/hotplug: Ignore pm_wakeup_pending() for disable_nonboot_cpus() cpu/hotplug: Hide cpu_up/down() cpu/hotplug: Move bringup of secondary CPUs out of smp_init() torture: Replace cpu_up/down() with add/remove_cpu() firmware: psci: Replace cpu_up/down() with add/remove_cpu() xen/cpuhotplug: Replace cpu_up/down() with device_online/offline() parisc: Replace cpu_up/down() with add/remove_cpu() sparc: Replace cpu_up/down() with add/remove_cpu() powerpc: Replace cpu_up/down() with add/remove_cpu() x86/smp: Replace cpu_up/down() with add/remove_cpu() arm64: hibernate: Use bringup_hibernate_cpu() cpu/hotplug: Provide bringup_hibernate_cpu() arm64: Use reboot_cpu instead of hardconding it to 0 arm64: Don't use disable_nonboot_cpus() ARM: Use reboot_cpu instead of hardcoding it to 0 ARM: Don't use disable_nonboot_cpus() ia64: Replace cpu_down() with smp_shutdown_nonboot_cpus() cpu/hotplug: Create a new function to shutdown nonboot cpus cpu/hotplug: Add new {add,remove}_cpu() functions sched/core: Remove rq.hrtick_csd_pending ...

cpu/hotplug: Ignore pm_wakeup_pending() for disable_nonboot_cpus()

2020-03-28T10:42:55Z

A recent change to freeze_secondary_cpus() which added an early abort if a wakeup is pending missed the fact that the function is also invoked for shutdown, reboot and kexec via disable_nonboot_cpus(). In case of disable_nonboot_cpus() the wakeup event needs to be ignored as the purpose is to terminate the currently running kernel. Add a 'suspend' argument which is only set when the freeze is in context of a suspend operation. If not set then an eventually pending wakeup event is ignored. Fixes: a66d955e910a ("cpu/hotplug: Abort disabling secondary CPUs if wakeup is pending") Reported-by: Boqun Feng Signed-off-by: Thomas Gleixner Cc: Pavankumar Kondeti Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/874kuaxdiz.fsf@nanos.tec.linutronix.de

cpu/hotplug: Hide cpu_up/down()

2020-03-25T11:59:38Z

Use separate functions for the device core to bring a CPU up and down. Users outside the device core must use add/remove_cpu() which will take care of extra housekeeping work like keeping sysfs in sync. Make cpu_up/down() static and replace the extra layer of indirection. [ tglx: Removed the extra wrapper functions and adjusted function names ] Signed-off-by: Qais Yousef Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20200323135110.30522-18-qais.yousef@arm.com

cpu/hotplug: Move bringup of secondary CPUs out of smp_init()

2020-03-25T11:59:37Z

This is the last direct user of cpu_up() before it can become an internal implementation detail of the cpu subsystem. Signed-off-by: Qais Yousef Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20200323135110.30522-17-qais.yousef@arm.com

cpu/hotplug: Provide bringup_hibernate_cpu()

2020-03-25T11:59:34Z

arm64 uses cpu_up() in the resume from hibernation code to ensure that the CPU on which the system hibernated is online. Provide a core function for this. [ tglx: Split out from the combo arm64 patch ] Signed-off-by: Qais Yousef Signed-off-by: Thomas Gleixner Acked-by: Catalin Marinas Cc: Will Deacon Link: https://lkml.kernel.org/r/20200323135110.30522-9-qais.yousef@arm.com

cpu/hotplug: Create a new function to shutdown nonboot cpus

2020-03-25T11:59:31Z

This function will be used later in machine_shutdown() for some architectures. disable_nonboot_cpus() is not safe to use when doing machine_down(), because it relies on freeze_secondary_cpus() which in turn is a suspend/resume related freeze and could abort if the logic detects any pending activities that can prevent finishing the offlining process. Signed-off-by: Qais Yousef Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20200323135110.30522-3-qais.yousef@arm.com

cpu/hotplug: Add new {add,remove}_cpu() functions

2020-03-25T11:59:31Z

The new functions use device_{online,offline}() which are userspace safe. This is in preparation to move cpu_{up, down} kernel users to use a safer interface that is not racy with userspace. Suggested-by: "Paul E. McKenney" Signed-off-by: Qais Yousef Signed-off-by: Thomas Gleixner Reviewed-by: Paul E. McKenney Link: https://lkml.kernel.org/r/20200323135110.30522-2-qais.yousef@arm.com

locking/percpu-rwsem, lockdep: Make percpu-rwsem use its own lockdep_map

2020-02-11T12:10:53Z

As preparation for replacing the embedded rwsem, give percpu-rwsem its own lockdep_map. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Reviewed-by: Davidlohr Bueso Acked-by: Will Deacon Acked-by: Waiman Long Tested-by: Juri Lelli Link: https://lkml.kernel.org/r/20200131151539.927625541@infradead.org

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

2020-01-28T18:07:09Z

Pull scheduler updates from Ingo Molnar: "These were the main changes in this cycle: - More -rt motivated separation of CONFIG_PREEMPT and CONFIG_PREEMPTION. - Add more low level scheduling topology sanity checks and warnings to filter out nonsensical topologies that break scheduling. - Extend uclamp constraints to influence wakeup CPU placement - Make the RT scheduler more aware of asymmetric topologies and CPU capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y - Make idle CPU selection more consistent - Various fixes, smaller cleanups, updates and enhancements - please see the git log for details" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) sched/fair: Define sched_idle_cpu() only for SMP configurations sched/topology: Assert non-NUMA topology masks don't (partially) overlap idle: fix spelling mistake "iterrupts" -> "interrupts" sched/fair: Remove redundant call to cpufreq_update_util() sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP sched/fair: calculate delta runnable load only when it's needed sched/cputime: move rq parameter in irqtime_account_process_tick stop_machine: Make stop_cpus() static sched/debug: Reset watchdog on all CPUs while processing sysrq-t sched/core: Fix size of rq::uclamp initialization sched/uclamp: Fix a bug in propagating uclamp value in new cgroups sched/fair: Load balance aggressively for SCHED_IDLE CPUs sched/fair : Improve update_sd_pick_busiest for spare capacity case watchdog: Remove soft_lockup_hrtimer_cnt and related code sched/rt: Make RT capacity-aware sched/fair: Make EAS wakeup placement consider uclamp restrictions sched/fair: Make task_fits_capacity() consider uclamp restrictions sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with() sched/uclamp: Make uclamp util helpers use and return UL values ...

cpu/SMT: Fix x86 link error without CONFIG_SYSFS

2020-01-09T16:31:45Z

When CONFIG_SYSFS is disabled, but CONFIG_HOTPLUG_SMT is enabled, the kernel fails to link: arch/x86/power/cpu.o: In function `hibernate_resume_nonboot_cpu_disable': (.text+0x38d): undefined reference to `cpuhp_smt_enable' arch/x86/power/hibernate.o: In function `arch_resume_nosmt': hibernate.c:(.text+0x291): undefined reference to `cpuhp_smt_enable' hibernate.c:(.text+0x29c): undefined reference to `cpuhp_smt_disable' Move the exported functions out of the #ifdef section into its own with the correct conditions. The patch that caused this is marked for stable backports, so this one may need to be backported as well. Fixes: ec527c318036 ("x86/power: Fix 'nosmt' vs hibernation triple fault during resume") Signed-off-by: Arnd Bergmann Signed-off-by: Thomas Gleixner Reviewed-by: Jiri Kosina Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20191210195614.786555-1-arnd@arndb.de