Kbuild conventionally uses $(shell cd ... && /bin/pwd) idiom to get
the absolute path of the directory because GNU Make 3.80, the minimal
supported version at that time, did not support $(abspath ...) or
$(realpath ...).

Commit 37d69ee3 ("docs: bump minimal GNU Make version to 3.81")
dropped the GNU Make 3.80 support, so we are now allowed to use those
make-builtin helpers.

This conversion will provide better portability without relying on
the pwd command or its location /bin/pwd.

I am intentionally using $(realpath ...) instead $(abspath ...) in
some places.  The difference between the two is $(realpath ...)
returns an empty string if the given path does not exist.  It is
convenient in places where we need to error-out if the makefile fails
to create an output directory.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NThierry Reding <treding@nvidia.com>

The autogenerated constants.py file was only being built on the initial
call, and if the constants.py.in file changed.  As we are utilising the
CPP hooks, we can successfully use the call if_changed_dep rules to
determine when to rebuild the file based on it's inclusions.

Link: http://lkml.kernel.org/r/1467127337-11135-3-git-send-email-kieran@bingham.xyzSigned-off-by: NKieran Bingham <kieran@bingham.xyz>
Reported-by: NJan Kiszka <jan.kiszka@web.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The constants.py generation, involves a rule to link into the main
makefile.  This rule has no command and generates a spurious warning
message in the build logs when CONFIG_SCRIPTS_GDB is enabled.

Fix simply by giving a no-op action

Link: http://lkml.kernel.org/r/1467127337-11135-2-git-send-email-kieran@bingham.xyzSigned-off-by: NKieran Bingham <kieran@bingham.xyz>
Reported-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some macro's and defines are needed when parsing memory, and without
compiling the kernel as -g3 they are not available in the debug-symbols.

We use the pre-processor here to extract constants to a dedicated module
for the linux debugger extensions

Top level Kbuild is used to call in and generate the constants file,
while maintaining dependencies on autogenerated files in
include/generated

Link: http://lkml.kernel.org/r/bc3df9c25f57ea72177c066a51a446fc19e2c27f.1462865983.git.jan.kiszka@siemens.comSigned-off-by: NKieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This provides the basic infrastructure to load kernel-specific python
helper scripts when debugging the kernel in gdb.

The loading mechanism is based on gdb loading for <objfile>-gdb.py when
opening <objfile>.  Therefore, this places a corresponding link to the
main helper script into the output directory that contains vmlinux.

The main scripts will pull in submodules containing Linux specific gdb
commands and functions.  To avoid polluting the source directory with
compiled python modules, we link to them from the object directory.

Due to gdb.parse_and_eval and string redirection for gdb.execute, we
depend on gdb >= 7.2.

This feature is enabled via CONFIG_GDB_SCRIPTS.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Acked-by: Michal Marek <mmarek@suse.cz>		[kbuild stuff]
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>