projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 16444a8a ACM |
1 | # |
| 2 | # Architectures that offer an FTRACE implementation should select HAVE_FTRACE: | |
| 3 | # | |
| 4 | config HAVE_FTRACE | |
| 5 | bool | |
| bc0c38d1 SR |
6 | |
| 7 | config TRACING | |
| 8 | bool | |
| 9 | select DEBUG_FS | |
| 10 | ||
| 1b29b018 SR |
11 | config FTRACE |
| 12 | bool "Kernel Function Tracer" | |
| 13 | depends on DEBUG_KERNEL && HAVE_FTRACE | |
| 14 | select FRAME_POINTER | |
| 15 | select TRACING | |
| 35e8e302 | 16 | select CONTEXT_SWITCH_TRACER |
| 1b29b018 SR |
17 | help |
| 18 | Enable the kernel to trace every kernel function. This is done | |
| 19 | by using a compiler feature to insert a small, 5-byte No-Operation | |
| 20 | instruction to the beginning of every kernel function, which NOP | |
| 21 | sequence is then dynamically patched into a tracer call when | |
| 22 | tracing is enabled by the administrator. If it's runtime disabled | |
| 23 | (the bootup default), then the overhead of the instructions is very | |
| 24 | small and not measurable even in micro-benchmarks. | |
| 35e8e302 SR |
25 | |
| 26 | config CONTEXT_SWITCH_TRACER | |
| 27 | bool "Trace process context switches" | |
| 28 | depends on DEBUG_KERNEL | |
| 29 | select TRACING | |
| 30 | select MARKERS | |
| 31 | help | |
| 32 | This tracer gets called from the context switch and records | |
| 33 | all switching of tasks. | |
| 34 |