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| author | Brian Gerst <brgerst@gmail.com> | 2009-02-08 09:58:39 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-02-09 10:30:30 +0100 |
| commit | 2add8e235cbe0dcd672c33fc322754e15500238c (patch) | |
| tree | 3cf9abe886432ac82fc08e99241ec7254dc20193 /arch/x86/kernel | |
| parent | d3770449d3cb058b94ca1d050d5ced4a66c75ce4 (diff) | |
| download | talos-obmc-linux-2add8e235cbe0dcd672c33fc322754e15500238c.tar.gz talos-obmc-linux-2add8e235cbe0dcd672c33fc322754e15500238c.zip | |
x86: use linker to offset symbols by __per_cpu_load
Impact: cleanup and bug fix
Use the linker to create symbols for certain per-cpu variables
that are offset by __per_cpu_load. This allows the removal of
the runtime fixup of the GDT pointer, which fixes a bug with
resume reported by Jiri Slaby.
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/head_64.S | 21 | ||||
| -rw-r--r-- | arch/x86/kernel/vmlinux_64.lds.S | 8 |
3 files changed, 11 insertions, 24 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 0f73ea423089..41b0de6df873 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -902,12 +902,8 @@ struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table }; DEFINE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __aligned(PAGE_SIZE); -#ifdef CONFIG_SMP -DEFINE_PER_CPU(char *, irq_stack_ptr); /* will be set during per cpu init */ -#else DEFINE_PER_CPU(char *, irq_stack_ptr) = - per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64; -#endif + init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64; DEFINE_PER_CPU(unsigned long, kernel_stack) = (unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE; diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index a0a2b5ca9b7d..2e648e3a5ea4 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -205,19 +205,6 @@ ENTRY(secondary_startup_64) pushq $0 popfq -#ifdef CONFIG_SMP - /* - * 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 initial_gs(%rip), %rax - cmpl $0, per_cpu__cpu_number(%rax) - jne 1f - addq %rax, early_gdt_descr_base(%rip) -1: -#endif /* * We must switch to a new descriptor in kernel space for the GDT * because soon the kernel won't have access anymore to the userspace @@ -275,11 +262,7 @@ ENTRY(secondary_startup_64) ENTRY(initial_code) .quad x86_64_start_kernel ENTRY(initial_gs) -#ifdef CONFIG_SMP - .quad __per_cpu_load -#else - .quad PER_CPU_VAR(irq_stack_union) -#endif + .quad INIT_PER_CPU_VAR(irq_stack_union) __FINITDATA ENTRY(stack_start) @@ -425,7 +408,7 @@ NEXT_PAGE(level2_spare_pgt) early_gdt_descr: .word GDT_ENTRIES*8-1 early_gdt_descr_base: - .quad per_cpu__gdt_page + .quad INIT_PER_CPU_VAR(gdt_page) ENTRY(phys_base) /* This must match the first entry in level2_kernel_pgt */ diff --git a/arch/x86/kernel/vmlinux_64.lds.S b/arch/x86/kernel/vmlinux_64.lds.S index 07f62d287ff0..087a7f2c639b 100644 --- a/arch/x86/kernel/vmlinux_64.lds.S +++ b/arch/x86/kernel/vmlinux_64.lds.S @@ -257,6 +257,14 @@ SECTIONS DWARF_DEBUG } + /* + * 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 = per_cpu__##x + __per_cpu_load +INIT_PER_CPU(gdt_page); +INIT_PER_CPU(irq_stack_union); + /* * Build-time check on the image size: */ |
