[patch 01/17] init: Provide arch_cpu_finalize_init()

Thomas Gleixner
2023-06-13T23:39:28Z

check_bugs() has become a dump ground for all sorts of activities to
finalize the CPU initialization before running the rest of the init code.

Most are empty, a few do actual bug checks, some do alternative patching
and some cobble a CPU advertisment string together....

Aside of that the current implementation requires duplicated function
declaration and mostly empty header files for them.

Provide a new function arch_cpu_finalize_init(). Provide a generic
declaration if CONFIG_ARCH_HAS_CPU_FINALIZE_INIT is selected and a stub
inline otherwise.

This requires a temporary #ifdef in start_kernel() which will be removed
along with check_bugs() once the architectures are converted over.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/Kconfig | 3 +++
include/linux/cpu.h | 6 ++++++
init/main.c | 4 ++++
3 files changed, 13 insertions(+)
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -285,6 +285,9 @@ config ARCH_HAS_DMA_SET_UNCACHED
config ARCH_HAS_DMA_CLEAR_UNCACHED
bool

+config ARCH_HAS_CPU_FINALIZE_INIT
+ bool
+
# Select if arch init_task must go in the __init_task_data section
config ARCH_TASK_STRUCT_ON_STACK
bool
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -184,6 +184,12 @@ void arch_cpu_idle_enter(void);
void arch_cpu_idle_exit(void);
void __noreturn arch_cpu_idle_dead(void);

+#ifdef CONFIG_ARCH_HAS_CPU_FINALIZE_INIT
+void arch_cpu_finalize_init(void);
+#else
+static inline void arch_cpu_finalize_init(void) { }
+#endif
+
int cpu_report_state(int cpu);
int cpu_check_up_prepare(int cpu);
void cpu_set_state_online(int cpu);
--- a/init/main.c
+++ b/init/main.c
@@ -1078,7 +1078,11 @@ asmlinkage __visible void __init __no_sa
taskstats_init_early();
delayacct_init();

+ arch_cpu_finalize_init();
+ /* Temporary conditional until everything has been converted */
+#ifndef CONFIG_ARCH_HAS_CPU_FINALIZE_INIT
check_bugs();
+#endif

acpi_subsystem_init();
arch_post_acpi_subsys_init();