scripts/gdb: provide linux constants
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.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Kbuild b/Kbuild
index f55cefd..3d0ae15 100644
--- a/Kbuild
+++ b/Kbuild
@@ -5,6 +5,7 @@
# 2) Generate timeconst.h
# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
# 4) Check for missing system calls
+# 5) Generate constants.py (may need bounds.h)
# Default sed regexp - multiline due to syntax constraints
define sed-y
@@ -96,5 +97,14 @@
missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
$(call cmd,syscalls)
+#####
+# 5) Generate constants for Python GDB integration
+#
+
+extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
+
+build_constants_py: $(obj)/$(timeconst-file) $(obj)/$(bounds-file)
+ @$(MAKE) $(build)=scripts/gdb/linux $@
+
# Keep these three files during make clean
no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile
index 6cf1ecf..cd129e6 100644
--- a/scripts/gdb/linux/Makefile
+++ b/scripts/gdb/linux/Makefile
@@ -8,4 +8,14 @@
endif
@:
-clean-files := *.pyc *.pyo $(if $(KBUILD_SRC),*.py)
+quiet_cmd_gen_constants_py = GEN $@
+ cmd_gen_constants_py = \
+ $(CPP) -E -x c -P $(c_flags) $< > $@ ;\
+ sed -i '1,/<!-- end-c-headers -->/d;' $@
+
+$(obj)/constants.py: $(SRCTREE)/$(obj)/constants.py.in
+ $(call if_changed,gen_constants_py)
+
+build_constants_py: $(obj)/constants.py
+
+clean-files := *.pyc *.pyo $(if $(KBUILD_SRC),*.py) $(obj)/constants.py
diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
new file mode 100644
index 0000000..79d9d00
--- /dev/null
+++ b/scripts/gdb/linux/constants.py.in
@@ -0,0 +1,32 @@
+/*
+ * gdb helper commands and functions for Linux kernel debugging
+ *
+ * Kernel constants derived from include files.
+ *
+ * Copyright (c) 2016 Linaro Ltd
+ *
+ * Authors:
+ * Kieran Bingham <kieran.bingham@linaro.org>
+ *
+ * This work is licensed under the terms of the GNU GPL version 2.
+ *
+ */
+
+/* We need to stringify expanded macros so that they can be parsed */
+#define STRING(x) #x
+#define XSTRING(x) STRING(x)
+
+#define LX_VALUE(x) LX_##x = x
+#define LX_GDBPARSED(x) LX_##x = gdb.parse_and_eval(XSTRING(x))
+
+/*
+ * IS_ENABLED generates (a || b) which is not compatible with python
+ * We can only switch on configuration items we know are available
+ * Therefore - IS_BUILTIN() is more appropriate
+ */
+#define LX_CONFIG(x) LX_##x = IS_BUILTIN(x)
+
+/* The build system will take care of deleting everything above this marker */
+<!-- end-c-headers -->
+
+import gdb
diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py
index d5943ec..6e0b0af 100644
--- a/scripts/gdb/vmlinux-gdb.py
+++ b/scripts/gdb/vmlinux-gdb.py
@@ -30,3 +30,4 @@
import linux.cpus
import linux.lists
import linux.proc
+ import linux.constants