x86: resize NR_IRQS for large machines

On machines with very large numbers of cpus, tables that are dimensioned
by NR_IRQS get very large, especially the irq_desc table.  They are also
very sparsely used.  When the cpu count is > MAX_IO_APICS, use MAX_IO_APICS
to set NR_IRQS, otherwise use NR_CPUS.

Signed-off-by: Alan Mayer <ajm@sgi.com>
Reviewed-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Alan Mayer 2008-03-26 16:11:31 -05:00 committed by Ingo Molnar
parent 492c2e476e
commit 6859a84029
2 changed files with 7 additions and 1 deletions

View File

@ -10,6 +10,8 @@
* <tomsoft@informatik.tu-chemnitz.de>
*/
#include <asm/apicdef.h>
#define TIMER_IRQ 0
/*
@ -31,7 +33,11 @@
#define FIRST_SYSTEM_VECTOR 0xef /* duplicated in hw_irq.h */
#if NR_CPUS < MAX_IO_APICS
#define NR_IRQS (NR_VECTORS + (32 * NR_CPUS))
#else
#define NR_IRQS (NR_VECTORS + (32 * MAX_IO_APICS))
#endif
#define NR_IRQ_VECTORS NR_IRQS
static inline int irq_canonicalize(int irq)

View File

@ -1,11 +1,11 @@
#ifndef _LINUX_KERNEL_STAT_H
#define _LINUX_KERNEL_STAT_H
#include <asm/irq.h>
#include <linux/smp.h>
#include <linux/threads.h>
#include <linux/percpu.h>
#include <linux/cpumask.h>
#include <asm/irq.h>
#include <asm/cputime.h>
/*