Buildroot offers a helper infrastructure to build some userspace tools
for the target available within the Linux kernel sources. Since their
-source code is part of the kernel source code, it is not very
-practical to use separate packages for them as they often need to be
-built with the same kernel version as the kernel being used on the
-target. The small Linux kernel tools infrastructure is a simplified
-packaging mechanism based on the generic package infrastructure to
-help building those tools.
+source code is part of the kernel source code, a special package,
++linux-tools+, exists and re-uses the sources of the Linux kernel that
+runs on the target.
Let's look at an example of a Linux tool. For a new Linux tool named
+foo+, create a new menu entry in the existing
-+linux/Config.tools.in+. This file will contain the option
++package/linux-tools/Config.in+. This file will contain the option
descriptions related to each kernel tool that will be used and
displayed in the configuration tool. It would basically look like:
------------------------------
-01: config BR2_LINUX_KERNEL_TOOL_FOO
+01: config BR2_PACKAGE_LINUX_TOOLS_FOO
02: bool "foo"
-03: help
-04: This is a comment that explains what foo kernel tool is.
-05:
-06: http://foosoftware.org/foo/
+03: select BR2_PACKAGE_LINUX_TOOLS
+04: help
+05: This is a comment that explains what foo kernel tool is.
+06:
+07: http://foosoftware.org/foo/
------------------------------
-The name of the option starts with the prefix +BR2_LINUX_KERNEL_TOOL_+,
+The name of the option starts with the prefix +BR2_PACKAGE_LINUX_TOOLS_+,
followed by the uppercase name of the tool (like is done for packages).
-Then for each linux tool, add a new +.mk+ file named +linux/linux-tool-foo.mk+.
-It would basically look like:
+.Note
+Unlike other packages, the +linux-tools+ package options appear in the
++linux+ kernel menu, under the `Linux Kernel Tools` sub-menu, not under
+the `Target packages` main menu.
+
+Then for each linux tool, add a new +.mk+ file named
++package/linux-tools/linux-tool-foo.mk+. It would basically look like:
------------------------------
01: ################################################################################
09: FOO_DEPENDENCIES = libbbb
10:
11: define FOO_BUILD_CMDS
-12: $(TARGET_MAKE_ENV) $(MAKE) -C $(@D)/tools foo
+12: $(TARGET_MAKE_ENV) $(MAKE) -C $(LINUX_DIR)/tools foo
13: endef
14:
15: define FOO_INSTALL_STAGING_CMDS
-16: $(TARGET_MAKE_ENV) $(MAKE) -C $(@D)/tools \
-17: DESTDIR=$(STAGING_DIR) \
-18: foo_install
+16: $(TARGET_MAKE_ENV) $(MAKE) -C $(LINUX_DIR)/tools \
+17: DESTDIR=$(STAGING_DIR) \
+18: foo_install
19: endef
20:
21: define FOO_INSTALL_TARGET_CMDS
-22: $(TARGET_MAKE_ENV) $(MAKE) -C $(@D)/tools \
-23: DESTDIR=$(@D) \
-24: foo_install
+22: $(TARGET_MAKE_ENV) $(MAKE) -C $(LINUX_DIR)/tools \
+23: DESTDIR=$(TARGET_DIR) \
+24: foo_install
25: endef
--------------------------------
.Note
One *must not* call +$(eval $(generic-package))+ or any other
package infrastructure! Linux tools are not packages by themselves,
-they are part of the +linux+ package.
+they are part of the +linux-tools+ package.
[[linux-kernel-ext]]
==== linux-kernel-extensions