x86: change FIRST_SYSTEM_VECTOR to a variable

The SGI UV system needs several more system vectors than a vanilla
x86_64 system.  Rather than burden the other archs with extra system
vectors that they don't use, change FIRST_SYSTEM_VECTOR to a variable,
so that it can be dynamic.

Signed-off-by: Alan Mayer <ajm@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/x86/kernel/io_apic_64.c b/arch/x86/kernel/io_apic_64.c
index ef1a8dfcc52..f1e1ae3e5c7 100644
--- a/arch/x86/kernel/io_apic_64.c
+++ b/arch/x86/kernel/io_apic_64.c
@@ -82,6 +82,10 @@ struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = {
 
 static int assign_irq_vector(int irq, cpumask_t mask);
 
+int first_system_vector = 0xfe;
+
+char system_vectors[NR_VECTORS] = { [0 ... NR_VECTORS-1] = SYS_VECTOR_FREE};
+
 #define __apicdebuginit  __init
 
 int sis_apic_bug; /* not actually supported, dummy for compile */
@@ -730,7 +734,7 @@ static int __assign_irq_vector(int irq, cpumask_t mask)
                 offset = current_offset;
 next:
                 vector += 8;
-                if (vector >= FIRST_SYSTEM_VECTOR) {
+                if (vector >= first_system_vector) {
                         /* If we run out of vectors on large boxen, must share them. */
                         offset = (offset + 1) % 8;
                         vector = FIRST_DEVICE_VECTOR + offset;