kstat: modify kstat_irqs_legacy to be variable sized

Impact: reduce memory usage.

Allocate kstat_irqs_legacy based on nr_cpu_ids to deal with this
memory usage bump when NR_CPUS bumped from 128 to 4096:

     8192   +253952    262144 +3100%  kstat_irqs_legacy(.bss)

This is only when CONFIG_SPARSE_IRQS=y.

Signed-off-by: Mike Travis <travis@sgi.com>
This commit is contained in:
Mike Travis 2009-01-10 22:24:07 -08:00 committed by Ingo Molnar
parent 9332fccded
commit 542d865bbe

View file

@ -124,8 +124,7 @@ static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_sm
}
};
/* FIXME: use bootmem alloc ...*/
static unsigned int kstat_irqs_legacy[NR_IRQS_LEGACY][NR_CPUS];
static unsigned int *kstat_irqs_legacy;
int __init early_irq_init(void)
{
@ -144,9 +143,14 @@ int __init early_irq_init(void)
/* allocate irq_desc_ptrs array based on nr_irqs */
irq_desc_ptrs = alloc_bootmem(nr_irqs * sizeof(void *));
/* allocate based on nr_cpu_ids */
/* FIXME: invert kstat_irgs, and it'd be a per_cpu_alloc'd thing */
kstat_irqs_legacy = alloc_bootmem(NR_IRQS_LEGACY * nr_cpu_ids *
sizeof(int));
for (i = 0; i < legacy_count; i++) {
desc[i].irq = i;
desc[i].kstat_irqs = kstat_irqs_legacy[i];
desc[i].kstat_irqs = kstat_irqs_legacy + i * nr_cpu_ids;
lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
init_alloc_desc_masks(&desc[i], 0, true);
irq_desc_ptrs[i] = desc + i;