irq: Make refcount_interrupt kunit test selectable

Currently, refcount_interrupt_test is built unconditionally when
CONFIG_KUNIT is enabled, causing it to run unexpectedly during boot.

Fix this by introducing CONFIG_REFCOUNT_INTERRUPT_KUNIT_TEST so the
test can be configured independently, following standard kunit
practices.

Fixes: 07a88e2bcd ("irq: Add KUnit test for refcounted interrupt enable/disable")
Signed-off-by: Kuan-Wei Chiu <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Lyude Paul <[email protected]>
Reviewed-by: Radu Rendec <[email protected]>
Reviewed-by: Boqun Feng <[email protected]>
Link: https://patch.msgid.link/[email protected]

kernel/irq/Kconfig

@@ -150,6 +150,18 @@ config IRQ_KUNIT_TEST
 
 	  If unsure, say N.
 
+config REFCOUNT_INTERRUPT_KUNIT_TEST
+	tristate "Test refcounted interrupt enable/disable" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  This builds the kunit tests for the refcounted interrupt
+	  infrastructure. It verifies the correctness of single, nested,
+	  and multiple interrupt enable/disable state changes and ensures
+	  that the underlying reference counting mechanisms work as expected.
+
+	  If unsure, say N.
+
 endmenu
 
 config GENERIC_IRQ_MULTI_HANDLER

kernel/irq/Makefile

@@ -16,4 +16,4 @@ obj-$(CONFIG_SMP) += affinity.o
 obj-$(CONFIG_GENERIC_IRQ_DEBUGFS) += debugfs.o
 obj-$(CONFIG_GENERIC_IRQ_MATRIX_ALLOCATOR) += matrix.o
 obj-$(CONFIG_IRQ_KUNIT_TEST) += irq_test.o
-obj-$(CONFIG_KUNIT) += refcount_interrupt_test.o
+obj-$(CONFIG_REFCOUNT_INTERRUPT_KUNIT_TEST) += refcount_interrupt_test.o