tests: kernel: smp_abort: add delay to ensure circular dependency
The test_smp_thread_abort_deadlock test assumes all CPUs will
simultaneously establish a circular abort dependency (each thread
aborts the next in a ring). However, on platforms with large
emulator/simulator quantum sizes, one thread's ISR may complete
and return before another thread even calls k_thread_abort() on it,
preventing the circular dependency from forming.
This manifested on ARMv8-R FVP but not on QEMU or ARMv8-A/ARMv9-A FVP
due to different timing characteristics and quantum sizes.
Add a k_busy_wait(100) after k_thread_abort() to give all CPUs time
to call abort before any ISR completes.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
diff --git a/tests/kernel/smp_abort/src/main.c b/tests/kernel/smp_abort/src/main.c
index 67b8003..fca519e 100644
--- a/tests/kernel/smp_abort/src/main.c
+++ b/tests/kernel/smp_abort/src/main.c
@@ -39,6 +39,15 @@
}
k_thread_abort(var->target); /* Abort thread on another CPU */
+
+ /*
+ * Give other CPUs time to also call k_thread_abort() to establish
+ * the circular dependency that this test is designed to exercise.
+ * On platforms with large emulator/simulator quantum sizes, without
+ * this delay one thread may complete its ISR and return before
+ * another thread even calls k_thread_abort() on it.
+ */
+ k_busy_wait(100);
}
static void thread_entry(void *p1, void *p2, void *p3)
