[RFC Patch V2 01/16] x86, irq: Split out alloc_ioapic_save_registers()

[Jiang Liu <jiang.liu@linux.intel.com>]

From: Yinghai Lu <yinghai@kernel.org>

Split alloc_ioapic_save_registers() from early_irq_init(),
so it will be used per ioapic.

Will call that later for hot-added ioapic controller.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
---
 arch/x86/kernel/apic/io_apic.c |   22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 26490336ef6f..e97ec28f5269 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -237,6 +237,19 @@ static struct irq_pin_list *alloc_irq_pin_list(int node)
 	return kzalloc_node(sizeof(struct irq_pin_list), GFP_KERNEL, node);
 }
 
+static void alloc_ioapic_saved_registers(int idx)
+{
+	size_t size;
+
+	if (ioapics[idx].saved_registers)
+		return;
+
+	size = sizeof(struct IO_APIC_route_entry) * ioapics[idx].nr_registers;
+	ioapics[idx].saved_registers = kzalloc(size, GFP_KERNEL);
+	if (!ioapics[idx].saved_registers)
+		pr_err("IOAPIC %d: suspend/resume impossible!\n", idx);
+}
+
 int __init arch_early_irq_init(void)
 {
 	struct irq_cfg *cfg;
@@ -245,13 +258,8 @@ int __init arch_early_irq_init(void)
 	if (!nr_legacy_irqs())
 		io_apic_irqs = ~0UL;
 
-	for_each_ioapic(i) {
-		ioapics[i].saved_registers =
-			kzalloc(sizeof(struct IO_APIC_route_entry) *
-				ioapics[i].nr_registers, GFP_KERNEL);
-		if (!ioapics[i].saved_registers)
-			pr_err("IOAPIC %d: suspend/resume impossible!\n", i);
-	}
+	for_each_ioapic(i)
+		alloc_ioapic_saved_registers(i);
 
 	/*
 	 * For legacy IRQ's, start with assigning irq0 to irq15 to
-- 
1.7.10.4