kernel: copy kernel build dir on Per-Device Initramfs compilation

To speedup compilation of Per-Device Initramfs, copy the kernel build directory for each rootfs ID. This permits concurrent execution of kernel build without conflicting with each other at the expense of additional disk space usage. To limit disk space usage, the copied kernel directory is deleted after the Per-Device Initramfs image is generated and saved. Link: openwrt/openwrt#16404 Signed-off-by: Christian Marangi <[email protected]>
lede-project · Sep 17, 2024 · d78dec3 · d78dec3
1 parent 52cc9d8
commit d78dec3
Showing 1 changed file with 10 additions and 9 deletions.
diff --git a/include/kernel-defaults.mk b/include/kernel-defaults.mk
@@ -153,13 +153,13 @@ endif
 # $1: image suffix
 # $2: Per Device Rootfs ID
 define Kernel/CopyImage
-	cmp -s $(LINUX_DIR)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).debug$(2) || { \
-		$(KERNEL_CROSS)objcopy -O binary $(OBJCOPY_STRIP) -S $(LINUX_DIR)/vmlinux $(LINUX_KERNEL)$(1)$(2); \
-		$(KERNEL_CROSS)objcopy $(OBJCOPY_STRIP) -S $(LINUX_DIR)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).elf$(2); \
-		$(CP) $(LINUX_DIR)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).debug$(2); \
+	cmp -s $(LINUX_DIR)$(2)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).debug$(2) || { \
+		$(KERNEL_CROSS)objcopy -O binary $(OBJCOPY_STRIP) -S $(LINUX_DIR)$(2)/vmlinux $(LINUX_KERNEL)$(1)$(2); \
+		$(KERNEL_CROSS)objcopy $(OBJCOPY_STRIP) -S $(LINUX_DIR)$(2)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).elf$(2); \
+		$(CP) $(LINUX_DIR)$(2)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).debug$(2); \
 		$(foreach k, \
 			$(if $(KERNEL_IMAGES),$(KERNEL_IMAGES),$(filter-out vmlinux dtbs,$(KERNELNAME))), \
-			$(CP) $(LINUX_DIR)/arch/$(LINUX_KARCH)/boot/$(IMAGES_DIR)/$(k) $(KERNEL_BUILD_DIR)/$(k)$(1)$(2); \
+			$(CP) $(LINUX_DIR)$(2)/arch/$(LINUX_KARCH)/boot/$(IMAGES_DIR)/$(k) $(KERNEL_BUILD_DIR)/$(k)$(1)$(2); \
 		) \
 	}
 endef
@@ -173,7 +173,9 @@ endef
 define Kernel/PrepareConfigPerRootfs
 	{ \
 		[ ! -d "$(1)" ] || rm -rf $(1); \
-		mkdir $(1) && $(CP) $(LINUX_DIR)/.config $(1); \
+		mkdir $(1) && $(CP) -T $(LINUX_DIR) $(1); \
+		touch $(1)/.config; \
+		rm -rf $(1)/usr/initramfs_data.cpio*; \
 	}
 endef
 
@@ -209,10 +211,9 @@ define Kernel/CompileImage/Initramfs
 			$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_ZSTD), \
 				$(STAGING_DIR_HOST)/bin/zstd -T0 -f -o $(if $(2),$(LINUX_DIR)$(2),$(KERNEL_BUILD_DIR))/initrd.cpio.zstd $(if $(2),$(LINUX_DIR)$(2),$(KERNEL_BUILD_DIR))/initrd.cpio;) \
 			$(if $(2),,$(KERNEL_MAKE) $(KERNEL_MAKEOPTS_IMAGE) $(if $(KERNELNAME),$(KERNELNAME),all);),\
-			$(call locked,$(if $(2),$(CP) $(LINUX_DIR)$(2)/.config* $(LINUX_DIR) && touch $(LINUX_DIR)/.config && ) \
-				rm -rf $(LINUX_DIR)/usr/initramfs_data.cpio* $(LINUX_DIR)/.config.prev && \
-				$(KERNEL_MAKE) $(KERNEL_MAKEOPTS_IMAGE) $(if $(KERNELNAME),$(KERNELNAME),all), compile-initramfs);) \
+			$(KERNEL_MAKE) $(if $(2),-C $(LINUX_DIR)$(2)) $(KERNEL_MAKEOPTS_IMAGE) $(if $(KERNELNAME),$(KERNELNAME),all);) \
 		$(call Kernel/CopyImage,-initramfs,$(2)); \
+		$(if $(2),rm -rf $(LINUX_DIR)$(2);) \
 	}, gen-initramfs$(if $(2),-$(2)));
 endef
 else