Re: [PATCH] x86: move dmar_table_init out of enable_IR

Suresh Siddha
2009-08-17T18:34:35Z

On Mon, 2009-08-17 at 11:19 -0700, Yinghai Lu wrote:
> ---
> arch/x86/kernel/apic/apic.c | 22 +++++++++++++---------
> 1 file changed, 13 insertions(+), 9 deletions(-)
>
> Index: linux-2.6/arch/x86/kernel/apic/apic.c
> ===================================================================
> --- linux-2.6.orig/arch/x86/kernel/apic/apic.c
> +++ linux-2.6/arch/x86/kernel/apic/apic.c
> @@ -1365,14 +1365,6 @@ void enable_x2apic(void)
> int __init enable_IR(void)
> {
> #ifdef CONFIG_INTR_REMAP
> - int ret;
> -
> - ret = dmar_table_init();
> - if (ret) {
> - pr_debug("dmar_table_init() failed with %d:\n", ret);
> - return 0;
> - }
> -
> if (!intr_remapping_supported()) {
> pr_debug("intr-remapping not supported\n");
> return 0;
> @@ -1400,6 +1392,14 @@ void __init enable_IR_x2apic(void)
> unsigned long flags;
> struct IO_APIC_route_entry **ioapic_entries = NULL;
> int ret, x2apic_enabled = 0;
> + int dmar_table_init_ret = 0;
> +
> +#ifdef CONFIG_INTR_REMAP
> + dmar_table_init_ret = dmar_table_init();
> + if (dmar_table_init_ret)
> + pr_debug("dmar_table_init() failed with %d:\n",
> + dmar_table_init_ret);
> +#endif

We can remove this ifdef check, as dmar_table_init() already handles
the !config_intr_remap

Also, at this error condition, we should simply return if the cpu has no
x2apic support. There is no x2apic support and we failed to enable
interrupt-remapping. No need to go further down.

thanks,
suresh

>
> ioapic_entries = alloc_ioapic_entries();
> if (!ioapic_entries) {
> @@ -1417,7 +1417,11 @@ void __init enable_IR_x2apic(void)
> mask_8259A();
> mask_IO_APIC_setup(ioapic_entries);
>
> - ret = enable_IR();
> + if (dmar_table_init_ret)
> + ret = 0;
> + else
> + ret = enable_IR();
> +
> if (!ret) {
> /* IR is required if there is APIC ID > 255 even when running
> * under KVM
>