[PATCH v15 1/7] timers: Rename tmigr 'online' bit to 'available'

Gabriele Monaco posted 7 patches 1 month ago
[PATCH v15 1/7] timers: Rename tmigr 'online' bit to 'available'
Posted by Gabriele Monaco 1 month ago
The timer migration hierarchy excludes offline CPUs via the
tmigr_is_not_available function, which is essentially checking the
online bit for the CPU.

Rename the online bit to available and all references in function names
and tracepoint to generalise the concept of available CPUs.

Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
---
 include/trace/events/timer_migration.h |  4 ++--
 kernel/time/timer_migration.c          | 24 ++++++++++++------------
 kernel/time/timer_migration.h          |  2 +-
 3 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/include/trace/events/timer_migration.h b/include/trace/events/timer_migration.h
index 47db5eaf2f9a..61171b13c687 100644
--- a/include/trace/events/timer_migration.h
+++ b/include/trace/events/timer_migration.h
@@ -173,14 +173,14 @@ DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_active,
 	TP_ARGS(tmc)
 );
 
-DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_online,
+DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_available,
 
 	TP_PROTO(struct tmigr_cpu *tmc),
 
 	TP_ARGS(tmc)
 );
 
-DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_offline,
+DEFINE_EVENT(tmigr_cpugroup, tmigr_cpu_unavailable,
 
 	TP_PROTO(struct tmigr_cpu *tmc),
 
diff --git a/kernel/time/timer_migration.c b/kernel/time/timer_migration.c
index 19ddfa96b9df..d50514062a06 100644
--- a/kernel/time/timer_migration.c
+++ b/kernel/time/timer_migration.c
@@ -429,7 +429,7 @@ static DEFINE_PER_CPU(struct tmigr_cpu, tmigr_cpu);
 
 static inline bool tmigr_is_not_available(struct tmigr_cpu *tmc)
 {
-	return !(tmc->tmgroup && tmc->online);
+	return !(tmc->tmgroup && tmc->available);
 }
 
 /*
@@ -926,7 +926,7 @@ static void tmigr_handle_remote_cpu(unsigned int cpu, u64 now,
 	 * updated the event takes care when hierarchy is completely
 	 * idle. Otherwise the migrator does it as the event is enqueued.
 	 */
-	if (!tmc->online || tmc->remote || tmc->cpuevt.ignore ||
+	if (!tmc->available || tmc->remote || tmc->cpuevt.ignore ||
 	    now < tmc->cpuevt.nextevt.expires) {
 		raw_spin_unlock_irq(&tmc->lock);
 		return;
@@ -973,7 +973,7 @@ static void tmigr_handle_remote_cpu(unsigned int cpu, u64 now,
 	 * (See also section "Required event and timerqueue update after a
 	 * remote expiry" in the documentation at the top)
 	 */
-	if (!tmc->online || !tmc->idle) {
+	if (!tmc->available || !tmc->idle) {
 		timer_unlock_remote_bases(cpu);
 		goto unlock;
 	}
@@ -1422,19 +1422,19 @@ static long tmigr_trigger_active(void *unused)
 {
 	struct tmigr_cpu *tmc = this_cpu_ptr(&tmigr_cpu);
 
-	WARN_ON_ONCE(!tmc->online || tmc->idle);
+	WARN_ON_ONCE(!tmc->available || tmc->idle);
 
 	return 0;
 }
 
-static int tmigr_cpu_offline(unsigned int cpu)
+static int tmigr_clear_cpu_available(unsigned int cpu)
 {
 	struct tmigr_cpu *tmc = this_cpu_ptr(&tmigr_cpu);
 	int migrator;
 	u64 firstexp;
 
 	raw_spin_lock_irq(&tmc->lock);
-	tmc->online = false;
+	tmc->available = false;
 	WRITE_ONCE(tmc->wakeup, KTIME_MAX);
 
 	/*
@@ -1442,7 +1442,7 @@ static int tmigr_cpu_offline(unsigned int cpu)
 	 * offline; Therefore nextevt value is set to KTIME_MAX
 	 */
 	firstexp = __tmigr_cpu_deactivate(tmc, KTIME_MAX);
-	trace_tmigr_cpu_offline(tmc);
+	trace_tmigr_cpu_unavailable(tmc);
 	raw_spin_unlock_irq(&tmc->lock);
 
 	if (firstexp != KTIME_MAX) {
@@ -1453,7 +1453,7 @@ static int tmigr_cpu_offline(unsigned int cpu)
 	return 0;
 }
 
-static int tmigr_cpu_online(unsigned int cpu)
+static int tmigr_set_cpu_available(unsigned int cpu)
 {
 	struct tmigr_cpu *tmc = this_cpu_ptr(&tmigr_cpu);
 
@@ -1462,11 +1462,11 @@ static int tmigr_cpu_online(unsigned int cpu)
 		return -EINVAL;
 
 	raw_spin_lock_irq(&tmc->lock);
-	trace_tmigr_cpu_online(tmc);
+	trace_tmigr_cpu_available(tmc);
 	tmc->idle = timer_base_is_idle();
 	if (!tmc->idle)
 		__tmigr_cpu_activate(tmc);
-	tmc->online = true;
+	tmc->available = true;
 	raw_spin_unlock_irq(&tmc->lock);
 	return 0;
 }
@@ -1758,7 +1758,7 @@ static int tmigr_add_cpu(unsigned int cpu)
 		 * The (likely) current CPU is expected to be online in the hierarchy,
 		 * otherwise the old root may not be active as expected.
 		 */
-		WARN_ON_ONCE(!per_cpu_ptr(&tmigr_cpu, raw_smp_processor_id())->online);
+		WARN_ON_ONCE(!per_cpu_ptr(&tmigr_cpu, raw_smp_processor_id())->available);
 		ret = tmigr_setup_groups(-1, old_root->numa_node, old_root, true);
 	}
 
@@ -1854,7 +1854,7 @@ static int __init tmigr_init(void)
 		goto err;
 
 	ret = cpuhp_setup_state(CPUHP_AP_TMIGR_ONLINE, "tmigr:online",
-				tmigr_cpu_online, tmigr_cpu_offline);
+				tmigr_set_cpu_available, tmigr_clear_cpu_available);
 	if (ret)
 		goto err;
 
diff --git a/kernel/time/timer_migration.h b/kernel/time/timer_migration.h
index ae19f70f8170..70879cde6fdd 100644
--- a/kernel/time/timer_migration.h
+++ b/kernel/time/timer_migration.h
@@ -97,7 +97,7 @@ struct tmigr_group {
  */
 struct tmigr_cpu {
 	raw_spinlock_t		lock;
-	bool			online;
+	bool			available;
 	bool			idle;
 	bool			remote;
 	struct tmigr_group	*tmgroup;
-- 
2.51.1
Re: [PATCH v15 1/7] timers: Rename tmigr 'online' bit to 'available'
Posted by Thomas Gleixner 4 weeks, 1 day ago
On Thu, Nov 13 2025 at 09:33, Gabriele Monaco wrote:
> The timer migration hierarchy excludes offline CPUs via the
> tmigr_is_not_available function, which is essentially checking the
> online bit for the CPU.
>
> Rename the online bit to available and all references in function names
> and tracepoint to generalise the concept of available CPUs.
>
> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
> Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>