ANDROID: GKI: sched: stub sched_isolate symbols

These are needed to let modules load during compliance testing, but the
underlying core-isolation feature is not necessary for android-common.

Bug: 149816871
Test: compiled, checked abi diff for missing sched_*isolate* symbols
Signed-off-by: Quentin Perret <qperret@google.com>
Change-Id: Iaece1e98f821c50f2497b4a47b60714f49272750

kernel/sched/Makefile

@@ -19,6 +19,7 @@ endif
 obj-y += core.o loadavg.o clock.o cputime.o
 obj-y += idle.o fair.o rt.o deadline.o
 obj-y += wait.o wait_bit.o swait.o completion.o
+obj-y += stubs.o
 
 obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o topology.o stop_task.o pelt.o
 obj-$(CONFIG_SCHED_AUTOGROUP) += autogroup.o

kernel/sched/stubs.c

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Symbols stubs needed for GKI compliance
+ */
+
+#include "sched.h"
+
+int sched_isolate_cpu(int cpu)
+{
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(sched_isolate_cpu);
+
+int sched_unisolate_cpu_unlocked(int cpu)
+{
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(sched_unisolate_cpu_unlocked);
+
+int sched_unisolate_cpu(int cpu)
+{
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(sched_unisolate_cpu);
+
+int set_task_boost(int boost, u64 period)
+{
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(set_task_boost);