User:Gso321/My kernel setup

Here is my personal kernel setup:

First, emerge the Kernel, Linux-headers, and Git:

root #emerge --ask =sys-kernel/gentoo-sources-6.3.0 =sys-kernel/linux-headers-6.3 =dev-vcs/git-2.39.2

Symlink, then cd to /usr/src/linux:

user $cd /usr/src/linux

Finally, make:

root #make -j9 KCFLAGS="-fipa-pta -march=native -mmovbe" HOSTCFLAGS="-fipa-pta -march=native -mmovbe"

Using -fmerge-all-constants

Warning
This patch may only work on my machine, not yours.

Important
Kernel PROBLEMS: Screen stuck at "Loading initial ramdisk"

Causes: drivers/acpi don't work with -fmerge-all-constants.

Potential solutions: Either no ACPI with -fmerge-all-constants or edit ACPI itself (Gigachad move right there :)).

First, git apply the patch:

FILE merge-a-const.patch

diff --git a/Makefile b/Makefile
index 84447b0..8e1ac0f 100644
--- a/Makefile
+++ b/Makefile
@@ -749,6 +749,10 @@ endif # KBUILD_EXTMOD
 # Defaults to vmlinux, but the arch makefile usually adds further targets
 all: vmlinux
 
+ifdef CONFIG_MERGE_ALL_CONSTANTS
+KBUILD_CFLAGS += -fmerge-all-constants
+endif
+
 CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
 ifdef CONFIG_CC_IS_GCC
 CFLAGS_GCOV	+= -fno-tree-loop-im
diff --git a/arch/Kconfig b/arch/Kconfig
index e3511af..a821b1d 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -37,6 +37,14 @@ config HOTPLUG_SMT
 config GENERIC_ENTRY
 	bool
 
+config MERGE_ALL_CONSTANTS
+	bool "Set -fmerge-all-constants"
+	depends on $(cc-option,-fmerge-all-constants)
+	help
+	  Add -fmerge-all-constants to kernel, a more aggressive optimization
+	  than -fmerge-constants. Because so many C code assumes identical
+	  variables to be in different locations, this is disabled by default.
+
 config KPROBES
 	bool "Kprobes"
 	depends on MODULES
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index feb36c0..2ea26d0 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -3,6 +3,8 @@
 # Makefile for the Linux ACPI interpreter
 #
 
+subdir-ccflags-$(CONFIG_MERGE_ALL_CONSTANTS) += -fno-merge-all-constants
+
 ccflags-$(CONFIG_ACPI_DEBUG)	+= -DACPI_DEBUG_OUTPUT
 
 #

root #git apply merge-a-const.patch

Then enable CONFIG_MERGE_ALL_CONSTANTS:

KERNEL Enable -fmerge-all-constants (CONFIG_MERGE_ALL_CONSTANTS)

General architecture-dependent options  --->
    [*] Set -fmerge-all-constants