Add internal interface to determine if a SpinLock is cooperative.

Some use cases of SpinLock need to verify that it is configured for
non-cooperative scheduling.

PiperOrigin-RevId: 575278400
Change-Id: Ic49f57a989a3f7f67e346a1ec545f4cd5b94f849

1 files changed, 13 insertions, 0 deletions

diff --git a/absl/base/spinlock_test_common.cc b/absl/base/spinlock_test_common.cc
index 52ecf580..e9047158 100644
--- a/absl/base/spinlock_test_common.cc
+++ b/absl/base/spinlock_test_common.cc
@@ -51,6 +51,8 @@ struct SpinLockTest {
   static int64_t DecodeWaitCycles(uint32_t lock_value) {
     return SpinLock::DecodeWaitCycles(lock_value);
   }
+
+  static bool IsCooperative(const SpinLock& l) { return l.IsCooperative(); }
 };
 
 namespace {
@@ -266,6 +268,17 @@ TEST(SpinLockWithThreads, DoesNotDeadlock) {
                        base_internal::NumCPUs() * 2);
 }
 
+TEST(SpinLockTest, IsCooperative) {
+  SpinLock default_constructor;
+  EXPECT_TRUE(SpinLockTest::IsCooperative(default_constructor));
+
+  SpinLock cooperative(base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL);
+  EXPECT_TRUE(SpinLockTest::IsCooperative(cooperative));
+
+  SpinLock kernel_only(base_internal::SCHEDULE_KERNEL_ONLY);
+  EXPECT_FALSE(SpinLockTest::IsCooperative(kernel_only));
+}
+
 }  // namespace
 }  // namespace base_internal
 ABSL_NAMESPACE_END