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 !ARCH_WANTS_NO_INSTR || CC_HAS_NO_PROFILE_FN_ATTR
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