x86: Add "make tinyconfig" to configure the tiniest possible kernel

Since commit 5d2acfc ("kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT") in 3.15-rc1, "make allnoconfig" disables every possible config option. However, a few configuration options (CC_OPTIMIZE_FOR_SIZE, OPTIMIZE_INLINING) produce a smaller kernel when turned on, and a few choices exist (compression, highmem, allocator) for which a non-default option produces a smaller kernel. Add a "tinyconfig" option, which starts from allnoconfig and then sets these options to configure the tiniest possible kernel. This provides a better baseline for embedded systems or efforts to reduce kernel size. Signed-off-by: Josh Triplett <[email protected]>
ambv · Aug 8, 2014 · 0da1d4a · 0da1d4a
1 parent 3aaefce
commit 0da1d4a
Show file tree

Hide file tree

Showing 3 changed files with 10 additions and 0 deletions.
diff --git a/arch/x86/configs/tiny.config b/arch/x86/configs/tiny.config
@@ -0,0 +1 @@
+CONFIG_NOHIGHMEM=y
diff --git a/kernel/configs/tiny.config b/kernel/configs/tiny.config
@@ -0,0 +1,4 @@
+CONFIG_CC_OPTIMIZE_FOR_SIZE=y
+CONFIG_KERNEL_XZ=y
+CONFIG_OPTIMIZE_INLINING=y
+CONFIG_SLOB=y
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
@@ -117,6 +117,10 @@ PHONY += kvmconfig
 kvmconfig:
 	$(call mergeconfig,kvm_guest)
 
+PHONY += tinyconfig
+tinyconfig: allnoconfig
+	$(call mergeconfig,tiny)
+
 # Help text used by make help
 help:
 	@echo  '  config	  - Update current config utilising a line-oriented program'
@@ -138,6 +142,7 @@ help:
 	@echo  '  listnewconfig   - List new options'
 	@echo  '  olddefconfig	  - Same as silentoldconfig but sets new symbols to their default value'
 	@echo  '  kvmconfig	  - Enable additional options for guest kernel support'
+	@echo  '  tinyconfig	  - Configure the tiniest possible kernel'
 
 # lxdialog stuff
 check-lxdialog  := $(srctree)/$(src)/lxdialog/check-lxdialog.sh