cmake: Add option for "mem: per-CPU allocator cache (ThunderX2 workaround)"

Change-Id: I7156cf433b2081246d1d9b8e4fde489609676ef1

kernel/cls.c

@@ -42,7 +42,9 @@ void cpu_local_var_init(void)
 		clv[i].monitor = monitor->cpu + i;
 		clv[i].rusage = rusage.cpu + i;
 		INIT_LIST_HEAD(&clv[i].smp_func_req_list);
+#ifdef ENABLE_PER_CPU_ALLOC_CACHE
 		clv[i].free_chunks.rb_node = NULL;
+#endif
 	}
 
 	cpu_local_var_initialized = 1;

kernel/include/cls.h

@@ -15,6 +15,7 @@
 
 #include <process.h>
 #include <syscall.h>
+#include <config.h>
 /*
  * CPU Local Storage (cls)
  */
@@ -103,8 +104,10 @@ struct cpu_local_var {
 
 	/* UTI */
 	void *uti_futex_resp;
+#ifdef ENABLE_PER_CPU_ALLOC_CACHE
 	/* Per-CPU memory allocator cache */
 	struct rb_root free_chunks;
+#endif
 } __attribute__((aligned(64)));
 
 extern int cpu_local_var_initialized;