aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pci
diff options
context:
space:
mode:
authorYinghai Lu <yinghai@kernel.org>2008-12-05 21:58:31 -0500
committerIngo Molnar <mingo@elte.hu>2008-12-08 08:31:51 -0500
commit0b8f1efad30bd58f89961b82dfe68b9edf8fd2ac (patch)
tree239251bad791fd60af8c0f2ba365b7188395c83f /drivers/pci
parent218d11a8b071b23b76c484fd5f72a4fe3306801e (diff)
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 'drivers/pci')
-rw-r--r--drivers/pci/intr_remapping.c76
1 files changed, 74 insertions, 2 deletions
diff --git a/drivers/pci/intr_remapping.c b/drivers/pci/intr_remapping.c
index 2de5a3238c94..c9958ec5e25e 100644
--- a/drivers/pci/intr_remapping.c
+++ b/drivers/pci/intr_remapping.c
@@ -19,17 +19,75 @@ struct irq_2_iommu {
19 u8 irte_mask; 19 u8 irte_mask;
20}; 20};
21 21
22static struct irq_2_iommu irq_2_iommuX[NR_IRQS]; 22#ifdef CONFIG_SPARSE_IRQ
23static struct irq_2_iommu *get_one_free_irq_2_iommu(int cpu)
24{
25 struct irq_2_iommu *iommu;
26 int node;
27
28 node = cpu_to_node(cpu);
29
30 iommu = kzalloc_node(sizeof(*iommu), GFP_ATOMIC, node);
31 printk(KERN_DEBUG "alloc irq_2_iommu on cpu %d node %d\n", cpu, node);
32
33 return iommu;
34}
23 35
24static struct irq_2_iommu *irq_2_iommu(unsigned int irq) 36static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
25{ 37{
26 return (irq < nr_irqs) ? irq_2_iommuX + irq : NULL; 38 struct irq_desc *desc;
39
40 desc = irq_to_desc(irq);
41
42 if (WARN_ON_ONCE(!desc))
43 return NULL;
44
45 return desc->irq_2_iommu;
46}
47
48static struct irq_2_iommu *irq_2_iommu_alloc_cpu(unsigned int irq, int cpu)
49{
50 struct irq_desc *desc;
51 struct irq_2_iommu *irq_iommu;
52
53 /*
54 * alloc irq desc if not allocated already.
55 */
56 desc = irq_to_desc_alloc_cpu(irq, cpu);
57 if (!desc) {
58 printk(KERN_INFO "can not get irq_desc for %d\n", irq);
59 return NULL;
60 }
61
62 irq_iommu = desc->irq_2_iommu;
63
64 if (!irq_iommu)
65 desc->irq_2_iommu = get_one_free_irq_2_iommu(cpu);
66
67 return desc->irq_2_iommu;
27} 68}
28 69
29static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq) 70static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq)
30{ 71{
72 return irq_2_iommu_alloc_cpu(irq, boot_cpu_id);
73}
74
75#else /* !CONFIG_SPARSE_IRQ */
76
77static struct irq_2_iommu irq_2_iommuX[NR_IRQS];
78
79static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
80{
81 if (irq < nr_irqs)
82 return &irq_2_iommuX[irq];
83
84 return NULL;
85}
86static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq)
87{
31 return irq_2_iommu(irq); 88 return irq_2_iommu(irq);
32} 89}
90#endif
33 91
34static DEFINE_SPINLOCK(irq_2_ir_lock); 92static DEFINE_SPINLOCK(irq_2_ir_lock);
35 93
@@ -86,9 +144,11 @@ int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
86 if (!count) 144 if (!count)
87 return -1; 145 return -1;
88 146
147#ifndef CONFIG_SPARSE_IRQ
89 /* protect irq_2_iommu_alloc later */ 148 /* protect irq_2_iommu_alloc later */
90 if (irq >= nr_irqs) 149 if (irq >= nr_irqs)
91 return -1; 150 return -1;
151#endif
92 152
93 /* 153 /*
94 * start the IRTE search from index 0. 154 * start the IRTE search from index 0.
@@ -130,6 +190,12 @@ int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
130 table->base[i].present = 1; 190 table->base[i].present = 1;
131 191
132 irq_iommu = irq_2_iommu_alloc(irq); 192 irq_iommu = irq_2_iommu_alloc(irq);
193 if (!irq_iommu) {
194 spin_unlock(&irq_2_ir_lock);
195 printk(KERN_ERR "can't allocate irq_2_iommu\n");
196 return -1;
197 }
198
133 irq_iommu->iommu = iommu; 199 irq_iommu->iommu = iommu;
134 irq_iommu->irte_index = index; 200 irq_iommu->irte_index = index;
135 irq_iommu->sub_handle = 0; 201 irq_iommu->sub_handle = 0;
@@ -177,6 +243,12 @@ int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
177 243
178 irq_iommu = irq_2_iommu_alloc(irq); 244 irq_iommu = irq_2_iommu_alloc(irq);
179 245
246 if (!irq_iommu) {
247 spin_unlock(&irq_2_ir_lock);
248 printk(KERN_ERR "can't allocate irq_2_iommu\n");
249 return -1;
250 }
251
180 irq_iommu->iommu = iommu; 252 irq_iommu->iommu = iommu;
181 irq_iommu->irte_index = index; 253 irq_iommu->irte_index = index;
182 irq_iommu->sub_handle = subhandle; 254 irq_iommu->sub_handle = subhandle;