Re: [RFC PATCH 5/6] gcov: add gcov profiling infrastructure

[Andrew Morton <akpm@linux-foundation.org>]

On Mon, 05 May 2008 17:24:46 +0200 Peter Oberparleiter <peter.oberparleiter@de.ibm.com> wrote:

> +config GCOV_PROFILE
> +	bool "Activate gcov-based profiling"
> +	depends on DEBUG_FS
> +	---help---
> +	This option enables gcov-based code profiling (e.g. for code coverage
> +	measurements).
> +
> +	If unsure, say N.
> +
> +	Additionally specify CONFIG_GCOV_PROFILE_ALL=y to get profiling data
> +	for the entire kernel. To enable profiling for specific files or
> +	directories, add a line similar to the following to the respective
> +	Makefile:
> +
> +	For a single file (e.g. main.o):
> +	        GCOV_main.o := y
> +
> +	For all files in one directory:
> +	        GCOV := y
> +
> +	To exclude files from being profiled even when CONFIG_GCOV_PROFILE_ALL
> +	is specified, use:
> +
> +	        GCOV_main.o := n
> +	and:
> +	        GCOV := n
> +
> +	Note that the debugfs filesystem has to be mounted to access
> +	profiling data.
> +
> +config GCOV_PROFILE_ALL
> +	bool "Profile entire Kernel"
> +	depends on GCOV_PROFILE
> +	---help---
> +	This options activates profiling for the entire kernel.
> +
> +	If unsure, say Y.
> +
> +	Note that a kernel compiled with profiling flags will be larger and
> +	slower. Also be sure to exclude files from profiling which are not
> +	linked to the kernel image to prevent linker errors.

umm....  I think the Kconfig help should include the text "makes your
kernel three times larger".