1# SPDX-License-Identifier: GPL-2.0-only 2menu "GCOV-based kernel profiling" 3 4config GCOV_KERNEL 5 bool "Enable gcov-based kernel profiling" 6 depends on DEBUG_FS 7 depends on !CC_IS_CLANG || CLANG_VERSION >= 110000 8 select CONSTRUCTORS 9 default n 10 help 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 37config ARCH_HAS_GCOV_PROFILE_ALL 38 def_bool n 39 40config GCOV_PROFILE_ALL 41 bool "Profile entire Kernel" 42 depends on !COMPILE_TEST 43 depends on GCOV_KERNEL 44 depends on ARCH_HAS_GCOV_PROFILE_ALL 45 default n 46 help 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 55endmenu 56