Thomas Gleixner | ec8f24b | 2019-05-19 13:07:45 +0100 | [diff] [blame] | 1 | # SPDX-License-Identifier: GPL-2.0-only |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 2 | menu "GCOV-based kernel profiling" |
| 3 | |
| 4 | config GCOV_KERNEL |
| 5 | bool "Enable gcov-based kernel profiling" |
Josh Triplett | d2c3225 | 2011-06-15 15:08:47 -0700 | [diff] [blame] | 6 | depends on DEBUG_FS |
Nick Desaulniers | 51c2ee6 | 2021-06-21 16:18:22 -0700 | [diff] [blame] | 7 | depends on !ARCH_WANTS_NO_INSTR || CC_HAS_NO_PROFILE_FN_ATTR |
Johannes Berg | 55b6f763 | 2021-02-04 18:32:28 -0800 | [diff] [blame] | 8 | select CONSTRUCTORS |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 9 | default n |
Masahiro Yamada | a7f7f62 | 2020-06-14 01:50:22 +0900 | [diff] [blame] | 10 | help |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 11 | This option enables gcov-based code profiling (e.g. for code coverage |
| 12 | measurements). |
| 13 | |
| 14 | If unsure, say N. |
| 15 | |
| 16 | Additionally specify CONFIG_GCOV_PROFILE_ALL=y to get profiling data |
| 17 | for the entire kernel. To enable profiling for specific files or |
| 18 | directories, add a line similar to the following to the respective |
| 19 | Makefile: |
| 20 | |
| 21 | For a single file (e.g. main.o): |
| 22 | GCOV_PROFILE_main.o := y |
| 23 | |
| 24 | For all files in one directory: |
| 25 | GCOV_PROFILE := y |
| 26 | |
| 27 | To exclude files from being profiled even when CONFIG_GCOV_PROFILE_ALL |
| 28 | is specified, use: |
| 29 | |
| 30 | GCOV_PROFILE_main.o := n |
| 31 | and: |
| 32 | GCOV_PROFILE := n |
| 33 | |
| 34 | Note that the debugfs filesystem has to be mounted to access |
| 35 | profiling data. |
| 36 | |
Riku Voipio | 957e3fa | 2014-12-12 16:57:44 -0800 | [diff] [blame] | 37 | config ARCH_HAS_GCOV_PROFILE_ALL |
| 38 | def_bool n |
| 39 | |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 40 | config GCOV_PROFILE_ALL |
| 41 | bool "Profile entire Kernel" |
Arnd Bergmann | cc62242 | 2016-04-25 17:35:29 +0200 | [diff] [blame] | 42 | depends on !COMPILE_TEST |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 43 | depends on GCOV_KERNEL |
Riku Voipio | 957e3fa | 2014-12-12 16:57:44 -0800 | [diff] [blame] | 44 | depends on ARCH_HAS_GCOV_PROFILE_ALL |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 45 | default n |
Masahiro Yamada | a7f7f62 | 2020-06-14 01:50:22 +0900 | [diff] [blame] | 46 | help |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 47 | This options activates profiling for the entire kernel. |
| 48 | |
| 49 | If unsure, say N. |
| 50 | |
| 51 | Note that a kernel compiled with profiling flags will be significantly |
| 52 | larger and run slower. Also be sure to exclude files from profiling |
| 53 | which are not linked to the kernel image to prevent linker errors. |
| 54 | |
Peter Oberparleiter | 2521f2c | 2009-06-17 16:28:08 -0700 | [diff] [blame] | 55 | endmenu |