2 # Architectures that offer an FTRACE implementation should select HAVE_FTRACE:
12 bool "Kernel Function Tracer"
13 depends on DEBUG_KERNEL && HAVE_FTRACE
17 Enable the kernel to trace every kernel function. This is done
18 by using a compiler feature to insert a small, 5-byte No-Operation
19 instruction to the beginning of every kernel function, which NOP
20 sequence is then dynamically patched into a tracer call when
21 tracing is enabled by the administrator. If it's runtime disabled
22 (the bootup default), then the overhead of the instructions is very
23 small and not measurable even in micro-benchmarks.