lkml.org 
[lkml]   [2009]   [Feb]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] x86/irq: optimizing nr_irqs -v2

Impact: more depend on cards to be used

depend on nr_irq_gsi more, and have a ratio for MSI

v2: make nr_irqs shoule less than NR_VECTORS * nr_cpu_ids
aka if only one cpu, we only can support nr_irqs = NR_VECTORS

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
arch/x86/kernel/io_apic.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)

Index: linux-2.6/arch/x86/kernel/io_apic.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/io_apic.c
+++ linux-2.6/arch/x86/kernel/io_apic.c
@@ -3482,9 +3482,9 @@ int arch_setup_msi_irqs(struct pci_dev *
sub_handle = 0;
list_for_each_entry(msidesc, &dev->msi_list, list) {
irq = create_irq_nr(irq_want);
- irq_want++;
if (irq == 0)
return -1;
+ irq_want = irq + 1;
#ifdef CONFIG_INTR_REMAP
if (!intr_remapping_enabled)
goto no_ir;
@@ -3838,11 +3838,17 @@ int __init arch_probe_nr_irqs(void)
{
int nr;

- nr = ((8 * nr_cpu_ids) > (32 * nr_ioapics) ?
- (NR_VECTORS + (8 * nr_cpu_ids)) :
- (NR_VECTORS + (32 * nr_ioapics)));
+ if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
+ nr_irqs = NR_VECTORS * nr_cpu_ids;

- if (nr < nr_irqs && nr > nr_irqs_gsi)
+ nr = nr_irqs_gsi + 8 * nr_cpu_ids;
+#if defined(CONFIG_PCI_MSI) || defined(CONFIG_HT_IRQ)
+ /*
+ * for MSI and HT dyn irq
+ */
+ nr += nr_irqs_gsi * 16;
+#endif
+ if (nr < nr_irqs)
nr_irqs = nr;

return 0;

\
 
 \ /
  Last update: 2009-02-08 10:47    [W:0.064 / U:1.476 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site