From: David Woodhouse <dwmw@xxxxxxxxxxxx>
This is the mask of CPUs to which IRQs can be delivered without interrupt
remapping.
Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
---
arch/x86/include/asm/mpspec.h | 1 +
arch/x86/kernel/apic/apic.c | 12 ++++++++++++
arch/x86/kernel/apic/io_apic.c | 2 ++
3 files changed, 15 insertions(+)
diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h
index 25ee8ca0a1f2..b2090be5b444 100644
--- a/arch/x86/include/asm/mpspec.h
+++ b/arch/x86/include/asm/mpspec.h
@@ -141,5 +141,6 @@ static inline void physid_set_mask_of_physid(int physid, physid_mask_t *map)
#define PHYSID_MASK_NONE { {[0 ... PHYSID_ARRAY_SIZE-1] = 0UL} }
extern physid_mask_t phys_cpu_present_map;
+extern cpumask_t x86_non_ir_cpumask;
#endif /* _ASM_X86_MPSPEC_H */
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 459c78558f36..069f5e9f1d28 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -103,6 +103,9 @@ EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid);
+/* Mask of CPUs which can be targeted by non-remapped interrupts. */
+cpumask_t x86_non_ir_cpumask = { CPU_BITS_ALL };
+
#ifdef CONFIG_X86_32
/*
@@ -1838,6 +1841,7 @@ static __init void x2apic_enable(void)
static __init void try_to_enable_x2apic(int remap_mode)
{
u32 apic_limit = 0;
+ int i;
if (x2apic_state == X2APIC_DISABLED)
return;
@@ -1880,6 +1884,14 @@ static __init void try_to_enable_x2apic(int remap_mode)
if (apic_limit)
x2apic_set_max_apicid(apic_limit);
+ /* Build the affinity mask for interrupts that can't be remapped. */
+ cpumask_clear(&x86_non_ir_cpumask);
+ i = min_t(unsigned int, num_possible_cpus() - 1, apic_limit);
+ for ( ; i >= 0; i--) {
+ if (cpu_physical_id(i) <= apic_limit)
+ cpumask_set_cpu(i, &x86_non_ir_cpumask);
+ }
+
x2apic_enable();
}
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index aa9a3b54a96c..4d0ef46fedb9 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2098,6 +2098,8 @@ static int mp_alloc_timer_irq(int ioapic, int pin)
struct irq_alloc_info info;
ioapic_set_alloc_attr(&info, NUMA_NO_NODE, 0, 0);
+ if (domain->parent == x86_vector_domain)
+ info.mask = &x86_non_ir_cpumask;
info.devid = mpc_ioapic_id(ioapic);
info.ioapic.pin = pin;
mutex_lock(&ioapic_mutex);
--
2.26.2
