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authorYinghai Lu <yinghai@kernel.org>2008-12-05 18:58:31 -0800
committerIngo Molnar <mingo@elte.hu>2008-12-08 14:31:51 +0100
commit0b8f1efad30bd58f89961b82dfe68b9edf8fd2ac (patch)
tree239251bad791fd60af8c0f2ba365b7188395c83f /arch/x86/kernel/irq_32.c
parent218d11a8b071b23b76c484fd5f72a4fe3306801e (diff)
downloadop-kernel-dev-0b8f1efad30bd58f89961b82dfe68b9edf8fd2ac.zip
op-kernel-dev-0b8f1efad30bd58f89961b82dfe68b9edf8fd2ac.tar.gz
sparse irq_desc[] array: core kernel and x86 changes
Impact: new feature Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with NR_CPUS set to large values. The goal is to be able to scale up to much larger NR_IRQS value without impacting the (important) common case. To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of irq_desc pointers. When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc, this also makes the IRQ descriptors NUMA-local (to the site that calls request_irq()). This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now uses desc->chip_data for x86 to store irq_cfg. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/irq_32.c')
-rw-r--r--arch/x86/kernel/irq_32.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index a513826..119fc9c 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -242,6 +242,8 @@ void fixup_irqs(cpumask_t map)
for_each_irq_desc(irq, desc) {
cpumask_t mask;
+ if (!desc)
+ continue;
if (irq == 2)
continue;
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