Merge tag 'timers-core-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "A large set of updates and features for timers and timekeeping:

   - The hierarchical timer pull model

     When timer wheel timers are armed they are placed into the timer
     wheel of a CPU which is likely to be busy at the time of expiry.
     This is done to avoid wakeups on potentially idle CPUs.

     This is wrong in several aspects:

       1) The heuristics to select the target CPU are wrong by
          definition as the chance to get the prediction right is
          close to zero.

       2) Due to #1 it is possible that timers are accumulated on
          a single target CPU

       3) The required computation in the enqueue path is just overhead
          for dubious value especially under the consideration that the
          vast majority of timer wheel timers are either canceled or
          rearmed before they expire.

     The timer pull model avoids the above by removing the target
     computation on enqueue and queueing timers always on the CPU on
     which they get armed.

     This is achieved by having separate wheels for CPU pinned timers
     and global timers which do not care about where they expire.

     As long as a CPU is busy it handles both the pinned and the global
     timers which are queued on the CPU local timer wheels.

     When a CPU goes idle it evaluates its own timer wheels:

       - If the first expiring timer is a pinned timer, then the global
         timers can be ignored as the CPU will wake up before they
         expire.

       - If the first expiring timer is a global timer, then the expiry
         time is propagated into the timer pull hierarchy and the CPU
         makes sure to wake up for the first pinned timer.

     The timer pull hierarchy organizes CPUs in groups of eight at the
     lowest level and at the next levels groups of eight groups up to
     the point where no further aggregation of groups is required, i.e.
     the number of levels is log8(NR_CPUS). The magic number of eight
     has been established by experimention, but can be adjusted if
     needed.

     In each group one busy CPU acts as the migrator. It's only one CPU
     to avoid lock contention on remote timer wheels.

     The migrator CPU checks in its own timer wheel handling whether
     there are other CPUs in the group which have gone idle and have
     global timers to expire. If there are global timers to expire, the
     migrator locks the remote CPU timer wheel and handles the expiry.

     Depending on the group level in the hierarchy this handling can
     require to walk the hierarchy downwards to the CPU level.

     Special care is taken when the last CPU goes idle. At this point
     the CPU is the systemwide migrator at the top of the hierarchy and
     it therefore cannot delegate to the hierarchy. It needs to arm its
     own timer device to expire either at the first expiring timer in
     the hierarchy or at the first CPU local timer, which ever expires
     first.

     This completely removes the overhead from the enqueue path, which
     is e.g. for networking a true hotpath and trades it for a slightly
     more complex idle path.

     This has been in development for a couple of years and the final
     series has been extensively tested by various teams from silicon
     vendors and ran through extensive CI.

     There have been slight performance improvements observed on network
     centric workloads and an Intel team confirmed that this allows them
     to power down a die completely on a mult-die socket for the first
     time in a mostly idle scenario.

     There is only one outstanding ~1.5% regression on a specific
     overloaded netperf test which is currently investigated, but the
     rest is either positive or neutral performance wise and positive on
     the power management side.

   - Fixes for the timekeeping interpolation code for cross-timestamps:

     cross-timestamps are used for PTP to get snapshots from hardware
     timers and interpolated them back to clock MONOTONIC. The changes
     address a few corner cases in the interpolation code which got the
     math and logic wrong.

   - Simplifcation of the clocksource watchdog retry logic to
     automatically adjust to handle larger systems correctly instead of
     having more incomprehensible command line parameters.

   - Treewide consolidation of the VDSO data structures.

   - The usual small improvements and cleanups all over the place"

* tag 'timers-core-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits)
  timer/migration: Fix quick check reporting late expiry
  tick/sched: Fix build failure for CONFIG_NO_HZ_COMMON=n
  vdso/datapage: Quick fix - use asm/page-def.h for ARM64
  timers: Assert no next dyntick timer look-up while CPU is offline
  tick: Assume timekeeping is correctly handed over upon last offline idle call
  tick: Shut down low-res tick from dying CPU
  tick: Split nohz and highres features from nohz_mode
  tick: Move individual bit features to debuggable mask accesses
  tick: Move got_idle_tick away from common flags
  tick: Assume the tick can't be stopped in NOHZ_MODE_INACTIVE mode
  tick: Move broadcast cancellation up to CPUHP_AP_TICK_DYING
  tick: Move tick cancellation up to CPUHP_AP_TICK_DYING
  tick: Start centralizing tick related CPU hotplug operations
  tick/sched: Don't clear ts::next_tick again in can_stop_idle_tick()
  tick/sched: Rename tick_nohz_stop_sched_tick() to tick_nohz_full_stop_tick()
  tick: Use IS_ENABLED() whenever possible
  tick/sched: Remove useless oneshot ifdeffery
  tick/nohz: Remove duplicate between lowres and highres handlers
  tick/nohz: Remove duplicate between tick_nohz_switch_to_nohz() and tick_setup_sched_timer()
  hrtimer: Select housekeeping CPU during migration
  ...

10 files changed, 461 insertions, 145 deletions

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 1d42d4b17327..0ad8b550bb4b 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -291,7 +291,19 @@ static inline void timer_probe(void) {}
 #define TIMER_ACPI_DECLARE(name, table_id, fn)		\
 	ACPI_DECLARE_PROBE_ENTRY(timer, name, table_id, 0, NULL, 0, fn)
 
-extern ulong max_cswd_read_retries;
+static inline unsigned int clocksource_get_max_watchdog_retry(void)
+{
+	/*
+	 * When system is in the boot phase or under heavy workload, there
+	 * can be random big latencies during the clocksource/watchdog
+	 * read, so allow retries to filter the noise latency. As the
+	 * latency's frequency and maximum value goes up with the number of
+	 * CPUs, scale the number of retries with the number of online
+	 * CPUs.
+	 */
+	return (ilog2(num_online_cpus()) / 2) + 1;
+}
+
 void clocksource_verify_percpu(struct clocksource *cs);
 
 #endif /* _LINUX_CLOCKSOURCE_H */
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 172d0a743e5d..35e78ddb2b37 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -184,6 +184,7 @@ enum cpuhp_state {
 	CPUHP_AP_ARM64_ISNDEP_STARTING,
 	CPUHP_AP_SMPCFD_DYING,
 	CPUHP_AP_HRTIMERS_DYING,
+	CPUHP_AP_TICK_DYING,
 	CPUHP_AP_X86_TBOOT_DYING,
 	CPUHP_AP_ARM_CACHE_B15_RAC_DYING,
 	CPUHP_AP_ONLINE,
@@ -231,6 +232,7 @@ enum cpuhp_state {
 	CPUHP_AP_PERF_POWERPC_HV_24x7_ONLINE,
 	CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE,
 	CPUHP_AP_PERF_CSKY_ONLINE,
+	CPUHP_AP_TMIGR_ONLINE,
 	CPUHP_AP_WATCHDOG_ONLINE,
 	CPUHP_AP_WORKQUEUE_ONLINE,
 	CPUHP_AP_RANDOM_ONLINE,
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 641c4567cfa7..aa1e65ccb615 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -18,12 +18,8 @@
 #include <linux/list.h>
 #include <linux/percpu-defs.h>
 #include <linux/rbtree.h>
-#include <linux/seqlock.h>
 #include <linux/timer.h>
 
-struct hrtimer_clock_base;
-struct hrtimer_cpu_base;
-
 /*
  * Mode arguments of xxx_hrtimer functions:
  *
@@ -98,107 +94,6 @@ struct hrtimer_sleeper {
 	struct task_struct *task;
 };
 
-#ifdef CONFIG_64BIT
-# define __hrtimer_clock_base_align	____cacheline_aligned
-#else
-# define __hrtimer_clock_base_align
-#endif
-
-/**
- * struct hrtimer_clock_base - the timer base for a specific clock
- * @cpu_base:		per cpu clock base
- * @index:		clock type index for per_cpu support when moving a
- *			timer to a base on another cpu.
- * @clockid:		clock id for per_cpu support
- * @seq:		seqcount around __run_hrtimer
- * @running:		pointer to the currently running hrtimer
- * @active:		red black tree root node for the active timers
- * @get_time:		function to retrieve the current time of the clock
- * @offset:		offset of this clock to the monotonic base
- */
-struct hrtimer_clock_base {
-	struct hrtimer_cpu_base	*cpu_base;
-	unsigned int		index;
-	clockid_t		clockid;
-	seqcount_raw_spinlock_t	seq;
-	struct hrtimer		*running;
-	struct timerqueue_head	active;
-	ktime_t			(*get_time)(void);
-	ktime_t			offset;
-} __hrtimer_clock_base_align;
-
-enum  hrtimer_base_type {
-	HRTIMER_BASE_MONOTONIC,
-	HRTIMER_BASE_REALTIME,
-	HRTIMER_BASE_BOOTTIME,
-	HRTIMER_BASE_TAI,
-	HRTIMER_BASE_MONOTONIC_SOFT,
-	HRTIMER_BASE_REALTIME_SOFT,
-	HRTIMER_BASE_BOOTTIME_SOFT,
-	HRTIMER_BASE_TAI_SOFT,
-	HRTIMER_MAX_CLOCK_BASES,
-};
-
-/**
- * struct hrtimer_cpu_base - the per cpu clock bases
- * @lock:		lock protecting the base and associated clock bases
- *			and timers
- * @cpu:		cpu number
- * @active_bases:	Bitfield to mark bases with active timers
- * @clock_was_set_seq:	Sequence counter of clock was set events
- * @hres_active:	State of high resolution mode
- * @in_hrtirq:		hrtimer_interrupt() is currently executing
- * @hang_detected:	The last hrtimer interrupt detected a hang
- * @softirq_activated:	displays, if the softirq is raised - update of softirq
- *			related settings is not required then.
- * @nr_events:		Total number of hrtimer interrupt events
- * @nr_retries:		Total number of hrtimer interrupt retries
- * @nr_hangs:		Total number of hrtimer interrupt hangs
- * @max_hang_time:	Maximum time spent in hrtimer_interrupt
- * @softirq_expiry_lock: Lock which is taken while softirq based hrtimer are
- *			 expired
- * @online:		CPU is online from an hrtimers point of view
- * @timer_waiters:	A hrtimer_cancel() invocation waits for the timer
- *			callback to finish.
- * @expires_next:	absolute time of the next event, is required for remote
- *			hrtimer enqueue; it is the total first expiry time (hard
- *			and soft hrtimer are taken into account)
- * @next_timer:		Pointer to the first expiring timer
- * @softirq_expires_next: Time to check, if soft queues needs also to be expired
- * @softirq_next_timer: Pointer to the first expiring softirq based timer
- * @clock_base:		array of clock bases for this cpu
- *
- * Note: next_timer is just an optimization for __remove_hrtimer().
- *	 Do not dereference the pointer because it is not reliable on
- *	 cross cpu removals.
- */
-struct hrtimer_cpu_base {
-	raw_spinlock_t			lock;
-	unsigned int			cpu;
-	unsigned int			active_bases;
-	unsigned int			clock_was_set_seq;
-	unsigned int			hres_active		: 1,
-					in_hrtirq		: 1,
-					hang_detected		: 1,
-					softirq_activated       : 1,
-					online			: 1;
-#ifdef CONFIG_HIGH_RES_TIMERS
-	unsigned int			nr_events;
-	unsigned short			nr_retries;
-	unsigned short			nr_hangs;
-	unsigned int			max_hang_time;
-#endif
-#ifdef CONFIG_PREEMPT_RT
-	spinlock_t			softirq_expiry_lock;
-	atomic_t			timer_waiters;
-#endif
-	ktime_t				expires_next;
-	struct hrtimer			*next_timer;
-	ktime_t				softirq_expires_next;
-	struct hrtimer			*softirq_next_timer;
-	struct hrtimer_clock_base	clock_base[HRTIMER_MAX_CLOCK_BASES];
-} ____cacheline_aligned;
-
 static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time)
 {
 	timer->node.expires = time;
@@ -447,20 +342,12 @@ extern u64
 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval);
 
 /**
- * hrtimer_forward_now - forward the timer expiry so it expires after now
+ * hrtimer_forward_now() - forward the timer expiry so it expires after now
  * @timer:	hrtimer to forward
  * @interval:	the interval to forward
  *
- * Forward the timer expiry so it will expire after the current time
- * of the hrtimer clock base. Returns the number of overruns.
- *
- * Can be safely called from the callback function of @timer. If
- * called from other contexts @timer must neither be enqueued nor
- * running the callback and the caller needs to take care of
- * serialization.
- *
- * Note: This only updates the timer expiry value and does not requeue
- * the timer.
+ * It is a variant of hrtimer_forward(). The timer will expire after the current
+ * time of the hrtimer clock base. See hrtimer_forward() for details.
  */
 static inline u64 hrtimer_forward_now(struct hrtimer *timer,
 				      ktime_t interval)
diff --git a/include/linux/hrtimer_defs.h b/include/linux/hrtimer_defs.h
index 2d3e3c5fb946..c3b4b7ed7c16 100644
--- a/include/linux/hrtimer_defs.h
+++ b/include/linux/hrtimer_defs.h
@@ -3,6 +3,8 @@
 #define _LINUX_HRTIMER_DEFS_H
 
 #include <linux/ktime.h>
+#include <linux/timerqueue.h>
+#include <linux/seqlock.h>
 
 #ifdef CONFIG_HIGH_RES_TIMERS
 
@@ -24,4 +26,106 @@
 
 #endif
 
+#ifdef CONFIG_64BIT
+# define __hrtimer_clock_base_align	____cacheline_aligned
+#else
+# define __hrtimer_clock_base_align
+#endif
+
+/**
+ * struct hrtimer_clock_base - the timer base for a specific clock
+ * @cpu_base:		per cpu clock base
+ * @index:		clock type index for per_cpu support when moving a
+ *			timer to a base on another cpu.
+ * @clockid:		clock id for per_cpu support
+ * @seq:		seqcount around __run_hrtimer
+ * @running:		pointer to the currently running hrtimer
+ * @active:		red black tree root node for the active timers
+ * @get_time:		function to retrieve the current time of the clock
+ * @offset:		offset of this clock to the monotonic base
+ */
+struct hrtimer_clock_base {
+	struct hrtimer_cpu_base	*cpu_base;
+	unsigned int		index;
+	clockid_t		clockid;
+	seqcount_raw_spinlock_t	seq;
+	struct hrtimer		*running;
+	struct timerqueue_head	active;
+	ktime_t			(*get_time)(void);
+	ktime_t			offset;
+} __hrtimer_clock_base_align;
+
+enum  hrtimer_base_type {
+	HRTIMER_BASE_MONOTONIC,
+	HRTIMER_BASE_REALTIME,
+	HRTIMER_BASE_BOOTTIME,
+	HRTIMER_BASE_TAI,
+	HRTIMER_BASE_MONOTONIC_SOFT,
+	HRTIMER_BASE_REALTIME_SOFT,
+	HRTIMER_BASE_BOOTTIME_SOFT,
+	HRTIMER_BASE_TAI_SOFT,
+	HRTIMER_MAX_CLOCK_BASES,
+};
+
+/**
+ * struct hrtimer_cpu_base - the per cpu clock bases
+ * @lock:		lock protecting the base and associated clock bases
+ *			and timers
+ * @cpu:		cpu number
+ * @active_bases:	Bitfield to mark bases with active timers
+ * @clock_was_set_seq:	Sequence counter of clock was set events
+ * @hres_active:	State of high resolution mode
+ * @in_hrtirq:		hrtimer_interrupt() is currently executing
+ * @hang_detected:	The last hrtimer interrupt detected a hang
+ * @softirq_activated:	displays, if the softirq is raised - update of softirq
+ *			related settings is not required then.
+ * @nr_events:		Total number of hrtimer interrupt events
+ * @nr_retries:		Total number of hrtimer interrupt retries
+ * @nr_hangs:		Total number of hrtimer interrupt hangs
+ * @max_hang_time:	Maximum time spent in hrtimer_interrupt
+ * @softirq_expiry_lock: Lock which is taken while softirq based hrtimer are
+ *			 expired
+ * @online:		CPU is online from an hrtimers point of view
+ * @timer_waiters:	A hrtimer_cancel() invocation waits for the timer
+ *			callback to finish.
+ * @expires_next:	absolute time of the next event, is required for remote
+ *			hrtimer enqueue; it is the total first expiry time (hard
+ *			and soft hrtimer are taken into account)
+ * @next_timer:		Pointer to the first expiring timer
+ * @softirq_expires_next: Time to check, if soft queues needs also to be expired
+ * @softirq_next_timer: Pointer to the first expiring softirq based timer
+ * @clock_base:		array of clock bases for this cpu
+ *
+ * Note: next_timer is just an optimization for __remove_hrtimer().
+ *	 Do not dereference the pointer because it is not reliable on
+ *	 cross cpu removals.
+ */
+struct hrtimer_cpu_base {
+	raw_spinlock_t			lock;
+	unsigned int			cpu;
+	unsigned int			active_bases;
+	unsigned int			clock_was_set_seq;
+	unsigned int			hres_active		: 1,
+					in_hrtirq		: 1,
+					hang_detected		: 1,
+					softirq_activated       : 1,
+					online			: 1;
+#ifdef CONFIG_HIGH_RES_TIMERS
+	unsigned int			nr_events;
+	unsigned short			nr_retries;
+	unsigned short			nr_hangs;
+	unsigned int			max_hang_time;
+#endif
+#ifdef CONFIG_PREEMPT_RT
+	spinlock_t			softirq_expiry_lock;
+	atomic_t			timer_waiters;
+#endif
+	ktime_t				expires_next;
+	struct hrtimer			*next_timer;
+	ktime_t				softirq_expires_next;
+	struct hrtimer			*softirq_next_timer;
+	struct hrtimer_clock_base	clock_base[HRTIMER_MAX_CLOCK_BASES];
+} ____cacheline_aligned;
+
+
 #endif
diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h
index e0ae2a43e0eb..d9f1435a5a13 100644
--- a/include/linux/jiffies.h
+++ b/include/linux/jiffies.h
@@ -102,12 +102,15 @@ static inline u64 get_jiffies_64(void)
 }
 #endif
 
-/*
- *	These inlines deal with timer wrapping correctly. You are
- *	strongly encouraged to use them:
- *	1. Because people otherwise forget
- *	2. Because if the timer wrap changes in future you won't have to
- *	   alter your driver code.
+/**
+ * DOC: General information about time_* inlines
+ *
+ * These inlines deal with timer wrapping correctly. You are strongly encouraged
+ * to use them:
+ *
+ * #. Because people otherwise forget
+ * #. Because if the timer wrap changes in future you won't have to alter your
+ *    driver code.
  */
 
 /**
diff --git a/include/linux/tick.h b/include/linux/tick.h
index 716d17f31c45..44fddfa93e18 100644
--- a/include/linux/tick.h
+++ b/include/linux/tick.h
@@ -19,16 +19,22 @@ extern void __init tick_init(void);
 extern void tick_suspend_local(void);
 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
 extern void tick_resume_local(void);
-extern void tick_handover_do_timer(void);
 extern void tick_cleanup_dead_cpu(int cpu);
 #else /* CONFIG_GENERIC_CLOCKEVENTS */
 static inline void tick_init(void) { }
 static inline void tick_suspend_local(void) { }
 static inline void tick_resume_local(void) { }
-static inline void tick_handover_do_timer(void) { }
 static inline void tick_cleanup_dead_cpu(int cpu) { }
 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
 
+#if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_HOTPLUG_CPU)
+extern int tick_cpu_dying(unsigned int cpu);
+extern void tick_assert_timekeeping_handover(void);
+#else
+#define tick_cpu_dying	NULL
+static inline void tick_assert_timekeeping_handover(void) { }
+#endif
+
 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
 extern void tick_freeze(void);
 extern void tick_unfreeze(void);
@@ -69,12 +75,6 @@ extern void tick_broadcast_control(enum tick_broadcast_mode mode);
 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
 #endif /* BROADCAST */
 
-#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
-extern void tick_offline_cpu(unsigned int cpu);
-#else
-static inline void tick_offline_cpu(unsigned int cpu) { }
-#endif
-
 #ifdef CONFIG_GENERIC_CLOCKEVENTS
 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
 #else
diff --git a/include/linux/timer.h b/include/linux/timer.h
index f18a2f1eb79e..14a633ba61d6 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -36,16 +36,10 @@
  * workqueue locking issues. It's not meant for executing random crap
  * with interrupts disabled. Abuse is monitored!
  *
- * @TIMER_PINNED: A pinned timer will not be affected by any timer
- * placement heuristics (like, NOHZ) and will always expire on the CPU
- * on which the timer was enqueued.
- *
- * Note: Because enqueuing of timers can migrate the timer from one
- * CPU to another, pinned timers are not guaranteed to stay on the
- * initialy selected CPU.  They move to the CPU on which the enqueue
- * function is invoked via mod_timer() or add_timer().  If the timer
- * should be placed on a particular CPU, then add_timer_on() has to be
- * used.
+ * @TIMER_PINNED: A pinned timer will always expire on the CPU on which the
+ * timer was enqueued. When a particular CPU is required, add_timer_on()
+ * has to be used. Enqueue via mod_timer() and add_timer() is always done
+ * on the local CPU.
  */
 #define TIMER_CPUMASK		0x0003FFFF
 #define TIMER_MIGRATING		0x00040000
@@ -165,6 +159,8 @@ extern int timer_reduce(struct timer_list *timer, unsigned long expires);
 #define NEXT_TIMER_MAX_DELTA	((1UL << 30) - 1)
 
 extern void add_timer(struct timer_list *timer);
+extern void add_timer_local(struct timer_list *timer);
+extern void add_timer_global(struct timer_list *timer);
 
 extern int try_to_del_timer_sync(struct timer_list *timer);
 extern int timer_delete_sync(struct timer_list *timer);
diff --git a/include/trace/events/timer_migration.h b/include/trace/events/timer_migration.h
new file mode 100644
index 000000000000..79f19e76a80b
--- /dev/null
+++ b/include/trace/events/timer_migration.h
@@ -0,0 +1,298 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM timer_migration
+
+#if !defined(_TRACE_TIMER_MIGRATION_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_TIMER_MIGRATION_H
+
+#include <linux/tracepoint.h>
+
+/* Group events */
+TRACE_EVENT(tmigr_group_set,
+
+	TP_PROTO(struct tmigr_group *group),
+
+	TP_ARGS(group),
+
+	TP_STRUCT__entry(
+		__field( void *,	group		)
+		__field( unsigned int,	lvl		)
+		__field( unsigned int,	numa_node	)
+	),
+
+	TP_fast_assign(
+		__entry->group		= group;
+		__entry->lvl		= group->level;
+		__entry->numa_node	= group->numa_node;
+	),
+
+	TP_printk("group=%p lvl=%d numa=%d",
+		  __entry->group, __entry->lvl, __entry->numa_node)
+);
+
+TRACE_EVENT(tmigr_connect_child_parent,
+
+	TP_PROTO(struct tmigr_group *child),
+
+	TP_ARGS(child),
+
+	TP_STRUCT__entry(
+		__field( void *,	child		)
+		__field( void *,	parent		)
+		__field( unsigned int,	lvl		)
+		__field( unsigned int,	numa_node	)
+		__field( unsigned int,	num_children	)
+		__field( u32,		childmask	)
+	),
+
+	TP_fast_assign(
+		__entry->child		= child;
+		__entry->parent		= child->parent;
+		__entry->lvl		= child->parent->level;
+		__entry->numa_node	= child->parent->numa_node;
+		__entry->num_children	= child->parent->num_children;
+		__entry->childmask	= child->childmask;
+	),
+
+	TP_printk("group=%p childmask=%0x parent=%p lvl=%d numa=%d num_children=%d",
+		  __entry->child,  __entry->childmask, __entry->parent,
+		  __entry->lvl, __entry->numa_node, __entry->num_children)
+);
+
+TRACE_EVENT(tmigr_connect_cpu_parent,
+
+	TP_PROTO(struct tmigr_cpu *tmc),
+
+	TP_ARGS(tmc),
+
+	TP_STRUCT__entry(
+		__field( void *,	parent		)
+		__field( unsigned int,	cpu		)
+		__field( unsigned int,	lvl		)
+		__field( unsigned int,	numa_node	)
+		__field( unsigned int,	num_children	)
+		__field( u32,		childmask	)
+	),
+
+	TP_fast_assign(
+		__entry->parent		= tmc->tmgroup;
+		__entry->cpu		= tmc->cpuevt.cpu;
+		__entry->lvl		= tmc->tmgroup->level;
+		__entry->numa_node	= tmc->tmgroup->numa_node;
+		__entry->num_children	= tmc->tmgroup->num_children;
+		__entry->childmask	= tmc->childmask;
+	),
+
+	TP_printk("cpu=%d childmask=%0x parent=%p lvl=%d numa=%d num_children=%d",
+		  __entry->cpu,	 __entry->childmask, __entry->parent,
+		  __entry->lvl, __entry->numa_node, __entry->num_children)
+);
+
+DECLARE_EVENT_CLASS(tmigr_group_and_cpu,
+
+	TP_PROTO(struct tmigr_group *group, union tmigr_state state, u32 childmask),
+
+	TP_ARGS(group, state, childmask),
+
+	TP_STRUCT__entry(
+		__field( void *,	group		)
+		__field( void *,	parent		)
+		__field( unsigned int,	lvl		)
+		__field( unsigned int,	numa_node	)
+		__field( u32,		childmask	)
+		__field( u8,		active		)
+		__field( u8,		migrator	)
+	),
+
+	TP_fast_assign(
+		__entry->group		= group;
+		__entry->parent		= group->parent;
+		__entry->lvl		= group->level;
+		__entry->numa_node	= group->numa_node;
+		__entry->childmask	= childmask;
+		__entry->active		= state.active;
+		__entry->migrator	= state.migrator;
+	),
+
+	TP_printk("group=%p lvl=%d numa=%d active=%0x migrator=%0x "
+		  "parent=%p childmask=%0x",
+		  __entry->group, __entry->lvl, __entry->numa_node,
+		  __entry->active, __entry->migrator,
+		  __entry->parent, __entry->childmask)
+);
+
+DEFINE_EVENT(tmigr_group_and_cpu, tmigr_group_set_cpu_inactive,
+
+	TP_PROTO(struct tmigr_group *group, union tmigr_state state, u32 childmask),
+
+	TP_ARGS(group, state, childmask)
+);
+
+DEFINE_EVENT(tmigr_group_and_cpu, tmigr_group_set_cpu_active,
+
+	TP_PROTO(struct tmigr_group *group, union tmigr_state state, u32 childmask),
+
+	TP_ARGS(group, state, childmask)
+);
+
+/* CPU events*/
+DECLARE_EVENT_CLASS(tmigr_cpugroup,
+
+	TP_PROTO(struct tmigr_cpu *tmc),
+
+	TP_ARGS(tmc),
+
+	TP_STRUCT__entry(
+		__field( u64,		wakeup	)
+		__field( void *,	parent	)
+		__field( unsigned int,	cpu	)
+
+	),
+
+	TP_fast_assign(
+		__entry->wakeup		= tmc->wakeup;
+		__entry->parent		= tmc->tmgroup;
+		__entry->cpu		= tmc->cpuevt.cpu;
+	),
+
+	TP_printk("cpu=%d parent=%p wakeup=%llu", __entry->cpu, __entry->parent, __entry->wakeup)
+);
+
+DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_new_timer,
+
+	TP_PROTO(struct tmigr_cpu *tmc),
+
+	TP_ARGS(tmc)
+);
+
+DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_active,
+
+	TP_PROTO(struct tmigr_cpu *tmc),
+
+	TP_ARGS(tmc)
+);
+
+DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_online,
+
+	TP_PROTO(struct tmigr_cpu *tmc),
+
+	TP_ARGS(tmc)
+);
+
+DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_offline,
+
+	TP_PROTO(struct tmigr_cpu *tmc),
+
+	TP_ARGS(tmc)
+);
+
+DEFINE_EVENT(tmigr_cpugroup, tmigr_handle_remote_cpu,
+
+	TP_PROTO(struct tmigr_cpu *tmc),
+
+	TP_ARGS(tmc)
+);
+
+DECLARE_EVENT_CLASS(tmigr_idle,
+
+	TP_PROTO(struct tmigr_cpu *tmc, u64 nextevt),
+
+	TP_ARGS(tmc, nextevt),
+
+	TP_STRUCT__entry(
+		__field( u64,		nextevt)
+		__field( u64,		wakeup)
+		__field( void *,	parent)
+		__field( unsigned int,	cpu)
+	),
+
+	TP_fast_assign(
+		__entry->nextevt	= nextevt;
+		__entry->wakeup		= tmc->wakeup;
+		__entry->parent		= tmc->tmgroup;
+		__entry->cpu		= tmc->cpuevt.cpu;
+	),
+
+	TP_printk("cpu=%d parent=%p nextevt=%llu wakeup=%llu",
+		  __entry->cpu, __entry->parent, __entry->nextevt, __entry->wakeup)
+);
+
+DEFINE_EVENT(tmigr_idle, tmigr_cpu_idle,
+
+	TP_PROTO(struct tmigr_cpu *tmc, u64 nextevt),
+
+	TP_ARGS(tmc, nextevt)
+);
+
+DEFINE_EVENT(tmigr_idle, tmigr_cpu_new_timer_idle,
+
+	TP_PROTO(struct tmigr_cpu *tmc, u64 nextevt),
+
+	TP_ARGS(tmc, nextevt)
+);
+
+TRACE_EVENT(tmigr_update_events,
+
+	TP_PROTO(struct tmigr_group *child, struct tmigr_group *group,
+		 union tmigr_state childstate,	union tmigr_state groupstate,
+		 u64 nextevt),
+
+	TP_ARGS(child, group, childstate, groupstate, nextevt),
+
+	TP_STRUCT__entry(
+		__field( void *,	child			)
+		__field( void *,	group			)
+		__field( u64,		nextevt			)
+		__field( u64,		group_next_expiry	)
+		__field( u64,		child_evt_expiry	)
+		__field( unsigned int,	group_lvl		)
+		__field( unsigned int,	child_evtcpu		)
+		__field( u8,		child_active		)
+		__field( u8,		group_active		)
+	),
+
+	TP_fast_assign(
+		__entry->child			= child;
+		__entry->group			= group;
+		__entry->nextevt		= nextevt;
+		__entry->group_next_expiry	= group->next_expiry;
+		__entry->child_evt_expiry	= child ? child->groupevt.nextevt.expires : 0;
+		__entry->group_lvl		= group->level;
+		__entry->child_evtcpu		= child ? child->groupevt.cpu : 0;
+		__entry->child_active		= childstate.active;
+		__entry->group_active		= groupstate.active;
+	),
+
+	TP_printk("child=%p group=%p group_lvl=%d child_active=%0x group_active=%0x "
+		  "nextevt=%llu next_expiry=%llu child_evt_expiry=%llu child_evtcpu=%d",
+		  __entry->child, __entry->group, __entry->group_lvl, __entry->child_active,
+		  __entry->group_active,
+		  __entry->nextevt, __entry->group_next_expiry, __entry->child_evt_expiry,
+		  __entry->child_evtcpu)
+);
+
+TRACE_EVENT(tmigr_handle_remote,
+
+	TP_PROTO(struct tmigr_group *group),
+
+	TP_ARGS(group),
+
+	TP_STRUCT__entry(
+		__field( void * ,	group	)
+		__field( unsigned int ,	lvl	)
+	),
+
+	TP_fast_assign(
+		__entry->group		= group;
+		__entry->lvl		= group->level;
+	),
+
+	TP_printk("group=%p lvl=%d",
+		   __entry->group, __entry->lvl)
+);
+
+#endif /*  _TRACE_TIMER_MIGRATION_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index 73eb622e7663..5d5c0b8efff2 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -19,6 +19,12 @@
 #include <vdso/time32.h>
 #include <vdso/time64.h>
 
+#ifdef CONFIG_ARM64
+#include <asm/page-def.h>
+#else
+#include <asm/page.h>
+#endif
+
 #ifdef CONFIG_ARCH_HAS_VDSO_DATA
 #include <asm/vdso/data.h>
 #else
@@ -121,6 +127,14 @@ struct vdso_data {
 extern struct vdso_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
 extern struct vdso_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
 
+/**
+ * union vdso_data_store - Generic vDSO data page
+ */
+union vdso_data_store {
+	struct vdso_data	data[CS_BASES];
+	u8			page[PAGE_SIZE];
+};
+
 /*
  * The generic vDSO implementation requires that gettimeofday.h
  * provides:
diff --git a/include/vdso/helpers.h b/include/vdso/helpers.h
index 9a2af9fca45e..73501149439d 100644
--- a/include/vdso/helpers.h
+++ b/include/vdso/helpers.h
@@ -30,9 +30,9 @@ static __always_inline u32 vdso_read_retry(const struct vdso_data *vd,
 static __always_inline void vdso_write_begin(struct vdso_data *vd)
 {
 	/*
-	 * WRITE_ONCE it is required otherwise the compiler can validly tear
+	 * WRITE_ONCE() is required otherwise the compiler can validly tear
 	 * updates to vd[x].seq and it is possible that the value seen by the
-	 * reader it is inconsistent.
+	 * reader is inconsistent.
 	 */
 	WRITE_ONCE(vd[CS_HRES_COARSE].seq, vd[CS_HRES_COARSE].seq + 1);
 	WRITE_ONCE(vd[CS_RAW].seq, vd[CS_RAW].seq + 1);
@@ -43,9 +43,9 @@ static __always_inline void vdso_write_end(struct vdso_data *vd)
 {
 	smp_wmb();
 	/*
-	 * WRITE_ONCE it is required otherwise the compiler can validly tear
+	 * WRITE_ONCE() is required otherwise the compiler can validly tear
 	 * updates to vd[x].seq and it is possible that the value seen by the
-	 * reader it is inconsistent.
+	 * reader is inconsistent.
 	 */
 	WRITE_ONCE(vd[CS_HRES_COARSE].seq, vd[CS_HRES_COARSE].seq + 1);
 	WRITE_ONCE(vd[CS_RAW].seq, vd[CS_RAW].seq + 1);