cached_vm_stacks  196 kernel/fork.c  	struct vm_struct **cached_vm_stacks = per_cpu_ptr(cached_stacks, cpu);
cached_vm_stacks  200 kernel/fork.c  		struct vm_struct *vm_stack = cached_vm_stacks[i];
cached_vm_stacks  206 kernel/fork.c  		cached_vm_stacks[i] = NULL;