X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/527f99514973766e9c0382a4d8550dfb00f54939..a39ff7e25e19b3a8c3020042a3872ca9ec9659f1:/osfmk/arm64/platform_tests.c?ds=inline

diff --git a/osfmk/arm64/platform_tests.c b/osfmk/arm64/platform_tests.c
index d5391b327..61b627419 100644
--- a/osfmk/arm64/platform_tests.c
+++ b/osfmk/arm64/platform_tests.c
@@ -425,6 +425,7 @@ static kern_return_t
 lt_test_trylocks()
 {
 	boolean_t success; 
+	extern unsigned int real_ncpus;
 	
 	/* 
 	 * First mtx try lock succeeds, second fails.
@@ -512,9 +513,15 @@ lt_test_trylocks()
 	lt_start_trylock_thread(lt_trylock_hw_lock_with_to);
 	success = hw_lock_to(&lt_hw_lock, 100);
 	T_ASSERT_NOTNULL(success, "First spin lock with timeout should succeed");
+	if (real_ncpus == 1) {
+		mp_enable_preemption(); /* if we re-enable preemption, the other thread can timeout and exit */
+	}
 	OSIncrementAtomic((volatile SInt32*)&lt_thread_lock_grabbed);
 	lt_wait_for_lock_test_threads();
 	T_ASSERT_NULL(lt_thread_lock_success, "Second spin lock with timeout should fail and timeout");
+	if (real_ncpus == 1) {
+		mp_disable_preemption(); /* don't double-enable when we unlock */
+	}
 	hw_lock_unlock(&lt_hw_lock);
 
 	lt_reset();
@@ -524,9 +531,15 @@ lt_test_trylocks()
 	OSMemoryBarrier();
 	lt_start_trylock_thread(lt_trylock_hw_lock_with_to);
 	hw_lock_lock(&lt_hw_lock);
+	if (real_ncpus == 1) {
+		mp_enable_preemption(); /* if we re-enable preemption, the other thread can timeout and exit */
+	}
 	OSIncrementAtomic((volatile SInt32*)&lt_thread_lock_grabbed);
 	lt_wait_for_lock_test_threads();
 	T_ASSERT_NULL(lt_thread_lock_success, "after taking a spin lock, lock attempt with timeout should fail");
+	if (real_ncpus == 1) {
+		mp_disable_preemption(); /* don't double-enable when we unlock */
+	}
 	hw_lock_unlock(&lt_hw_lock);
 
 	success = lck_spin_try_lock(&lt_lck_spin_t);
@@ -541,9 +554,15 @@ lt_test_trylocks()
 	lt_target_done_threads = 1;
 	lt_start_trylock_thread(lt_trylock_spin_try_lock);
 	lck_spin_lock(&lt_lck_spin_t);
+	if (real_ncpus == 1) {
+		mp_enable_preemption(); /* if we re-enable preemption, the other thread can timeout and exit */
+	}
 	OSIncrementAtomic((volatile SInt32*)&lt_thread_lock_grabbed);
 	lt_wait_for_lock_test_threads();
 	T_ASSERT_NULL(lt_thread_lock_success, "spin trylock attempt of previously held lock should fail");
+	if (real_ncpus == 1) {
+		mp_disable_preemption(); /* don't double-enable when we unlock */
+	}
 	lck_spin_unlock(&lt_lck_spin_t);
 
 	return KERN_SUCCESS;