On Sat, 12 Mar 2016, Jianyu Zhan wrote:
> During native_init_IRQ(), we will update first_system_vector conditionally
> when we init system vector. But on !CONFIG_X86_LOCAL_PIC, we prefer it
> to NR_IRQS, so don't bother set it on this case.
>
> Signed-off-by: Jianyu Zhan <[email protected]>
> ---
> arch/x86/include/asm/desc.h | 2 ++
> arch/x86/kernel/irqinit.c | 3 ---
> 2 files changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
> index 4e10d73..4fc2deb 100644
> --- a/arch/x86/include/asm/desc.h
> +++ b/arch/x86/include/asm/desc.h
> @@ -383,8 +383,10 @@ static inline void alloc_system_vector(int vector)
> {
> if (!test_bit(vector, used_vectors)) {
> set_bit(vector, used_vectors);
> +#ifdef CONFIG_X86_LOCAL_APIC
> if (first_system_vector > vector)
> first_system_vector = vector;
> +#endif
This is pointless, because it's only called when local apic is enabled as all
call sites of alloc_intr_gate() depend on CONFIG_X86_LOCAL_APIC ....
> } else {
> BUG();
> }
> diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
> index 0e9fa7c..e999b38 100644
> --- a/arch/x86/kernel/irqinit.c
> +++ b/arch/x86/kernel/irqinit.c
> @@ -188,9 +188,6 @@ void __init native_init_IRQ(void)
> * 'special' SMP interrupts)
> */
> i = FIRST_EXTERNAL_VECTOR;
> -#ifndef CONFIG_X86_LOCAL_APIC
> -#define first_system_vector NR_VECTORS
> -#endif
> for_each_clear_bit_from(i, used_vectors, first_system_vector) {
And how exactly is this here supposed to compile when CONFIG_X86_LOCAL_APIC=n?
> /* IA32_SYSCALL_VECTOR could be used in trap_init already. */
> set_intr_gate(i, irq_entries_start +
> --
> 2.4.3
>
>
