The streamline_config.pl finds all the configs that are needed to
compile the currently loaded modules. After it creates the .config
file, it tests to make sure all the configs that are needed were
set.
It only looks at the configs that are modules, it does not look
at the builtin configs. This causes unnecessary warnings about modules
not being covered.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
If a config does not have a prompt, it must be selected.
streamline_config.pl keeps track of all configs that select other configs.
If a config that does not have a prompt needs to be set to enable a
current module, it will include all configs that select it.
Note, streamline_config.pl does not enable modules that are not already
enabled. It only keeps enabled those that were enabled and might be
needed to compile the current modules.
The code to find the selects of a config is after the code that
adds the depends. But if a config needed selects but had no dependencies,
it would not be set. Because the code would stop before getting to
the select.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
streamline_config.pl is a very powerful tool. For those that install
a kernel to a new box using the config file from the distribution know that
it can take forever to compile the kernel.
Making a custom config file that will still boot your box, but bring
down the compile time of the kernel can be quit painful, and to ask
someone that reported a bug to do this can be a large burdon since that
person may not even know how to build a kernel.
This script will perform "lsmod" to find all the modules loaded on the
current running system. It will read all the Makefiles to map which
CONFIG enables a module. It will read the Kconfig files to find the
dependencies and selects that may be needed to support a CONFIG.
Finally, it reads the .config file and removes any module "=m" that is
not needed to enable the currently loaded modules. The output goes to
standard out.
Here's a way to run the script. From the Linux directory that holds
a distribution .config.
$ scripts/kconfig/streamline_config.pl arch/x86/Kconfig > config-sl
$ mv .config config-save
$ mv config-sl .config
$ make oldconfig
Now you have a .config that will still build all your modules, but also
take much less time to build the kernel.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>