[RFC PATCH 16/49] cpu: Move CPUHP_AP_PERF_XTENSA_STARTING post stop_machine()
From: Frederic Weisbecker
Date: Mon Oct 19 2026 - 09:16:54 EST
Between CPUHP_TEARDOWN_CPU and CPUHP_AP_OFFLINE, stop_machine executes
all the teardown callbacks while stopping all CPUs in the system. This
doesn't mix-up well with running RT or isolated tasks.
In order to transition smoothly from global stop_machine to finer
grained synchronization between teardown callbacks and the other CPUs,
a new stop machine post function has been introduced to be executed
after the main one with IRQs still disabled while other CPUs can exit
stop_machine().
This state doesn't have a teardown callback.
Move it to post stop_machine() accordingly.
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
---
kernel/cpu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 5a46372a8501..c20a822df803 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -1275,7 +1275,7 @@ void clear_tasks_mm_cpumask(int cpu)
static int take_cpu_down(void *_param)
{
struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state);
- enum cpuhp_state target = max((int)st->target, CPUHP_AP_PERF_X86_AMD_IBS_STARTING);
+ enum cpuhp_state target = max((int)st->target, CPUHP_AP_PERF_XTENSA_STARTING);
int err, cpu = smp_processor_id();
/* Ensure this CPU doesn't handle any more interrupts. */
@@ -1303,7 +1303,7 @@ static int take_cpu_down_post(void *_param)
enum cpuhp_state target = max((int)st->target, CPUHP_AP_OFFLINE);
int cpu = smp_processor_id();
- WARN_ON(st->state != CPUHP_AP_PERF_X86_AMD_IBS_STARTING);
+ WARN_ON(st->state != CPUHP_AP_PERF_XTENSA_STARTING);
/*
* Invoke the former CPU_DYING callbacks. DYING must not fail!
*/
--
2.53.0