From 8c7e58e690ae60ab4215b025f433ed4af261e103 Mon Sep 17 00:00:00 2001 From: Brian Gerst Date: Mon, 19 Jan 2009 12:21:28 +0900 Subject: [PATCH] x86: rework __per_cpu_load adjustments Impact: cleanup Use cpu_number to determine if the adjustment is necessary. Signed-off-by: Brian Gerst Signed-off-by: Tejun Heo --- arch/x86/kernel/head_64.S | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index c8ace880661b..98ea26a2fca1 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -207,19 +207,15 @@ ENTRY(secondary_startup_64) #ifdef CONFIG_SMP /* - * early_gdt_base should point to the gdt_page in static percpu init - * data area. Computing this requires two symbols - __per_cpu_load - * and per_cpu__gdt_page. As linker can't do no such relocation, do - * it by hand. As early_gdt_descr is manipulated by C code for - * secondary CPUs, this should be done only once for the boot CPU - * when early_gdt_descr_base contains zero. + * Fix up static pointers that need __per_cpu_load added. The assembler + * is unable to do this directly. This is only needed for the boot cpu. + * These values are set up with the correct base addresses by C code for + * secondary cpus. */ - movq early_gdt_descr_base(%rip), %rax - testq %rax, %rax - jnz 1f - movq $__per_cpu_load, %rax - addq $per_cpu__gdt_page, %rax - movq %rax, early_gdt_descr_base(%rip) + movq initial_gs(%rip), %rax + cmpl $0, per_cpu__cpu_number(%rax) + jne 1f + addq %rax, early_gdt_descr_base(%rip) 1: #endif /* @@ -431,12 +427,8 @@ NEXT_PAGE(level2_spare_pgt) .globl early_gdt_descr early_gdt_descr: .word GDT_ENTRIES*8-1 -#ifdef CONFIG_SMP early_gdt_descr_base: - .quad 0x0000000000000000 -#else .quad per_cpu__gdt_page -#endif ENTRY(phys_base) /* This must match the first entry in level2_kernel_pgt */