TRACE_CONTEXT_BITS  614 kernel/trace/trace.h #define TRACE_FTRACE_MAX	((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
TRACE_CONTEXT_BITS  617 kernel/trace/trace.h #define TRACE_LIST_MAX		((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)