x86/acpi: Switch to irq_get_nr_irqs() and irq_set_nr_irqs()

Use the irq_get_nr_irqs() and irq_set_nr_irqs() functions instead of the
global variable 'nr_irqs'. Prepare for changing 'nr_irqs' from an
exported global variable into a variable with file scope.

Signed-off-by: Bart Van Assche <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/[email protected]

Author: bvanassche

arch/x86/kernel/acpi/boot.c

@@ -1171,7 +1171,8 @@ static int __init acpi_parse_madt_ioapic_entries(void)
 	}
 
 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_INTERRUPT_OVERRIDE,
-				      acpi_parse_int_src_ovr, nr_irqs);
+				      acpi_parse_int_src_ovr,
+				      irq_get_nr_irqs());
 	if (count < 0) {
 		pr_err("Error parsing interrupt source overrides entry\n");
 		/* TBD: Cleanup to allow fallback to MPS */
@@ -1191,7 +1192,8 @@ static int __init acpi_parse_madt_ioapic_entries(void)
 	mp_config_acpi_legacy_irqs();
 
 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_NMI_SOURCE,
-				      acpi_parse_nmi_src, nr_irqs);
+				      acpi_parse_nmi_src,
+				      irq_get_nr_irqs());
 	if (count < 0) {
 		pr_err("Error parsing NMI SRC entry\n");
 		/* TBD: Cleanup to allow fallback to MPS */

arch/x86/kernel/apic/vector.c

@@ -712,8 +712,8 @@ int __init arch_probe_nr_irqs(void)
 {
 	int nr;
 
-	if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
-		nr_irqs = NR_VECTORS * nr_cpu_ids;
+	if (irq_get_nr_irqs() > NR_VECTORS * nr_cpu_ids)
+		irq_set_nr_irqs(NR_VECTORS * nr_cpu_ids);
 
 	nr = (gsi_top + nr_legacy_irqs()) + 8 * nr_cpu_ids;
 #if defined(CONFIG_PCI_MSI)
@@ -725,8 +725,8 @@ int __init arch_probe_nr_irqs(void)
 	else
 		nr += gsi_top * 16;
 #endif
-	if (nr < nr_irqs)
-		nr_irqs = nr;
+	if (nr < irq_get_nr_irqs())
+		irq_set_nr_irqs(nr);
 
 	/*
 	 * We don't know if PIC is present at this point so we need to do