[PATCH v4 12/16] x86/percpu/64: Remove INIT_PER_CPU macros

From: Brian Gerst
Date: Fri Mar 22 2024 - 12:55:41 EST


Now that the load and link addresses of percpu variables are the same,
these macros are no longer necessary.

Signed-off-by: Brian Gerst <brgerst@xxxxxxxxx>
---
arch/x86/include/asm/desc.h | 1 -
arch/x86/include/asm/percpu.h | 22 ----------------------
arch/x86/kernel/head64.c | 2 +-
arch/x86/kernel/irq_64.c | 1 -
arch/x86/kernel/vmlinux.lds.S | 7 -------
arch/x86/tools/relocs.c | 1 -
6 files changed, 1 insertion(+), 33 deletions(-)

diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index 62dc9f59ea76..ec95fe44fa3a 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -46,7 +46,6 @@ struct gdt_page {
} __attribute__((aligned(PAGE_SIZE)));

DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page);
-DECLARE_INIT_PER_CPU(gdt_page);

/* Provide the original GDT */
static inline struct desc_struct *get_cpu_gdt_rw(unsigned int cpu)
diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
index f6ddbaaf80bc..59d91fdfe037 100644
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -20,12 +20,6 @@

#define PER_CPU_VAR(var) __percpu(var)__percpu_rel

-#ifdef CONFIG_X86_64_SMP
-#define INIT_PER_CPU_VAR(var) init_per_cpu__##var
-#else
-#define INIT_PER_CPU_VAR(var) var
-#endif
-
#else /* ...!ASSEMBLY */

#include <linux/build_bug.h>
@@ -101,22 +95,6 @@
#define __percpu_arg(x) __percpu_prefix "%" #x
#define __force_percpu_arg(x) __force_percpu_prefix "%" #x

-/*
- * Initialized pointers to per-cpu variables needed for the boot
- * processor need to use these macros to get the proper address
- * offset from __per_cpu_load on SMP.
- *
- * There also must be an entry in vmlinux_64.lds.S
- */
-#define DECLARE_INIT_PER_CPU(var) \
- extern typeof(var) init_per_cpu_var(var)
-
-#ifdef CONFIG_X86_64_SMP
-#define init_per_cpu_var(var) init_per_cpu__##var
-#else
-#define init_per_cpu_var(var) var
-#endif
-
/* For arch-specific code, we can use direct single-insn ops (they
* don't give an lvalue though). */

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 212e8e06aeba..5f0523610e92 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -564,7 +564,7 @@ void __head startup_64_setup_gdt_idt(void)
void *handler = NULL;

struct desc_ptr startup_gdt_descr = {
- .address = (unsigned long)&RIP_REL_REF(init_per_cpu_var(gdt_page.gdt)),
+ .address = (unsigned long)&RIP_REL_REF(gdt_page.gdt),
.size = GDT_SIZE - 1,
};

diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index fe0c859873d1..30424f9876bc 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -26,7 +26,6 @@
#include <asm/apic.h>

DEFINE_PER_CPU_PAGE_ALIGNED(struct irq_stack, irq_stack_backing_store) __visible;
-DECLARE_INIT_PER_CPU(irq_stack_backing_store);

#ifdef CONFIG_VMAP_STACK
/*
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 667202ebd37f..8d5bf4a71e39 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -467,13 +467,6 @@ SECTIONS
"kernel image bigger than KERNEL_IMAGE_SIZE");

#ifdef CONFIG_X86_64
-/*
- * Per-cpu symbols which need to be offset from __per_cpu_load
- * for the boot processor.
- */
-#define INIT_PER_CPU(x) init_per_cpu__##x = ABSOLUTE(x)
-INIT_PER_CPU(gdt_page);
-INIT_PER_CPU(irq_stack_backing_store);

#ifdef CONFIG_MITIGATION_UNRET_ENTRY
. = ASSERT((retbleed_return_thunk & 0x3f) == 0, "retbleed_return_thunk not cacheline-aligned");
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index e490297a486b..8db231affba2 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -88,7 +88,6 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
"__initramfs_start|"
"(jiffies|jiffies_64)|"
#if ELF_BITS == 64
- "init_per_cpu__.*|"
"__end_rodata_hpage_align|"
#endif
"__vvar_page|"
--
2.44.0