Add CPUHP_AP_NO_HZ_FULL_DYING and CPUHP_AP_IRQ_AFFINITY_DYING to the
cpuhp_state enum.  These dying callbacks are invoked during CPU offline
before the tick is stopped, enabling clean tick handover and managed
IRQ migration when a CPU transitions between isolated and housekeeping
states.

The existing CPUHP_AP_IRQ_AFFINITY_ONLINE already handles managed IRQ
restoration on CPU online.  The new dying callback completes the pair,
migrating managed interrupts away from the CPU before it goes down.

Subsequent patches register handlers for these states.

Signed-off-by: Jing Wu <redacted>
Signed-off-by: Qiliang Yuan <redacted>
---
 include/linux/cpuhotplug.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 22ba327ec2278..075cfa8161334 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h

@@ -186,6 +186,8 @@ enum cpuhp_state {
 	CPUHP_AP_SMPCFD_DYING,
 	CPUHP_AP_HRTIMERS_DYING,
 	CPUHP_AP_TICK_DYING,
+	CPUHP_AP_IRQ_AFFINITY_DYING,
+	CPUHP_AP_NO_HZ_FULL_DYING,
 	CPUHP_AP_X86_TBOOT_DYING,
 	CPUHP_AP_ARM_CACHE_B15_RAC_DYING,
 	CPUHP_AP_ONLINE,

-- 
2.43.0