ktest.pl: Enhancements for 6.17

Some ktest.pl improvements:

- Add new -D option that allows to override variables and options

For example:

./ktest.pl -DPATCH_START:=HEAD~1 -DOUTPUT_DIR=/work/build/urgent config

The above sets the variable "PATCH_START" to HEAD~1 and the OUTPUT_DIR option to "/work/build/urgent".

This is useful because currently the only way to make a slight change to a config file is by modifying that config file. For one time changes, this can be annoying. Having a way to do a one time override from the command line simplifies the workflow.

Temp variables (PATCH_START) will override every temp variable in the config file, whereas options will act like a normal OVERRIDE option and will only affect the session they define.

-DBUILD_OUTPUT=/work/git/linux.git

Replaces the default BUILD_OUTPUT option.

     '-DBUILD_OUTPUT[2]=/work/git/linux.git'

Only replaces the BUILD_OUTPUT variable for test #2.

- If an option contains itself, just drop it instead of going into an infinite loop and failing to parse (it doesn't crash, it detects the recursion after 100 iterations anyway).

Some configs may define a variable with the same name as the option:

     ADD_CONFIG := $(ADD_CONFIG)

But if the option doesn't exist, it the above will fail to parse. In these cases, just ignore evaluating the option inside the definition of another option if it has the same name.

- Display the BUILD_DIR and OUTPUT_DIR options at the start of every test

It is useful to know which kernel source and what destination a test is using when it starts, in case a mistake is made. This makes it easier to abort the test if the wrong source or destination is being used instead of waiting until the test completes.

Steven Rostedt (5):
ktest.pl: Add -D option to override options
ktest.pl: Allow command option -D to override temp variables ktest.pl: Have -D option work without a space
ktest.pl: Prevent recursion of default variable options ktest.pl: Always display BUILD_DIR and OUTPUT_DIR at the start of tests

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 tools/testing/ktest/ktest.pl | 83 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 80 insertions(+), 3 deletions(-)