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WSL2-Linux-Kernel
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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>
This commit is contained in:
Yinghai Lu 2008-12-05 18:58:31 -08:00 коммит произвёл Ingo Molnar
Родитель 218d11a8b0
Коммит 0b8f1efad3
23 изменённых файлов: 659 добавлений и 173 удалений
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10
arch/x86/Kconfig
Просмотреть файл

@ -238,6 +238,16 @@ config X86_HAS_BOOT_CPU_ID
def_bool y
depends on X86_VOYAGER
config SPARSE_IRQ
bool "Support sparse irq numbering"
depends on PCI_MSI || HT_IRQ
default y
help
This enables support for sparse irq, esp for msi/msi-x. You may need
if you have lots of cards supports msi-x installed.
If you don't know what to do here, say Y.
config X86_FIND_SMP_CONFIG
def_bool y
depends on X86_MPPARSE || X86_VOYAGER

9
arch/x86/include/asm/irq_vectors.h
Просмотреть файл

@ -102,11 +102,20 @@
#define invalid_vm86_irq(irq) ((irq) < 3 || (irq) > 15)
#if defined(CONFIG_X86_IO_APIC) && !defined(CONFIG_X86_VOYAGER)
#ifndef CONFIG_SPARSE_IRQ
# 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
#else
# if (8 * NR_CPUS) > (32 * MAX_IO_APICS)
# define NR_IRQS (NR_VECTORS + (8 * NR_CPUS))
# else
# define NR_IRQS (NR_VECTORS + (32 * MAX_IO_APICS))
# endif
#endif
#elif defined(CONFIG_X86_VOYAGER)

321
arch/x86/kernel/io_apic.c
Просмотреть файл

@ -108,55 +108,6 @@ static int __init parse_noapic(char *str)
early_param("noapic", parse_noapic);
struct irq_pin_list;
struct irq_cfg {
unsigned int irq;
struct irq_pin_list *irq_2_pin;
cpumask_t domain;
cpumask_t old_domain;
unsigned move_cleanup_count;
u8 vector;
u8 move_in_progress : 1;
};
/* irq_cfg is indexed by the sum of all RTEs in all I/O APICs. */
static struct irq_cfg irq_cfgx[NR_IRQS] = {
[0] = { .irq = 0, .domain = CPU_MASK_ALL, .vector = IRQ0_VECTOR, },
[1] = { .irq = 1, .domain = CPU_MASK_ALL, .vector = IRQ1_VECTOR, },
[2] = { .irq = 2, .domain = CPU_MASK_ALL, .vector = IRQ2_VECTOR, },
[3] = { .irq = 3, .domain = CPU_MASK_ALL, .vector = IRQ3_VECTOR, },
[4] = { .irq = 4, .domain = CPU_MASK_ALL, .vector = IRQ4_VECTOR, },
[5] = { .irq = 5, .domain = CPU_MASK_ALL, .vector = IRQ5_VECTOR, },
[6] = { .irq = 6, .domain = CPU_MASK_ALL, .vector = IRQ6_VECTOR, },
[7] = { .irq = 7, .domain = CPU_MASK_ALL, .vector = IRQ7_VECTOR, },
[8] = { .irq = 8, .domain = CPU_MASK_ALL, .vector = IRQ8_VECTOR, },
[9] = { .irq = 9, .domain = CPU_MASK_ALL, .vector = IRQ9_VECTOR, },
[10] = { .irq = 10, .domain = CPU_MASK_ALL, .vector = IRQ10_VECTOR, },
[11] = { .irq = 11, .domain = CPU_MASK_ALL, .vector = IRQ11_VECTOR, },
[12] = { .irq = 12, .domain = CPU_MASK_ALL, .vector = IRQ12_VECTOR, },
[13] = { .irq = 13, .domain = CPU_MASK_ALL, .vector = IRQ13_VECTOR, },
[14] = { .irq = 14, .domain = CPU_MASK_ALL, .vector = IRQ14_VECTOR, },
[15] = { .irq = 15, .domain = CPU_MASK_ALL, .vector = IRQ15_VECTOR, },
};
#define for_each_irq_cfg(irq, cfg) \
for (irq = 0, cfg = irq_cfgx; irq < nr_irqs; irq++, cfg++)
static struct irq_cfg *irq_cfg(unsigned int irq)
{
return irq < nr_irqs ? irq_cfgx + irq : NULL;
}
static struct irq_cfg *irq_cfg_alloc(unsigned int irq)
{
return irq_cfg(irq);
}
/*
* Rough estimation of how many shared IRQs there are, can be changed
* anytime.
*/
#define MAX_PLUS_SHARED_IRQS NR_IRQS
#define PIN_MAP_SIZE (MAX_PLUS_SHARED_IRQS + NR_IRQS)
/*
* This is performance-critical, we want to do it O(1)
@ -170,32 +121,116 @@ struct irq_pin_list {
struct irq_pin_list *next;
};
static struct irq_pin_list irq_2_pin_head[PIN_MAP_SIZE];
static struct irq_pin_list *irq_2_pin_ptr;
static void __init irq_2_pin_init(void)
static struct irq_pin_list *get_one_free_irq_2_pin(int cpu)
{
struct irq_pin_list *pin = irq_2_pin_head;
int i;
struct irq_pin_list *pin;
int node;
for (i = 1; i < PIN_MAP_SIZE; i++)
pin[i-1].next = &pin[i];
node = cpu_to_node(cpu);
irq_2_pin_ptr = &pin[0];
}
pin = kzalloc_node(sizeof(*pin), GFP_ATOMIC, node);
printk(KERN_DEBUG " alloc irq_2_pin on cpu %d node %d\n", cpu, node);
static struct irq_pin_list *get_one_free_irq_2_pin(void)
{
struct irq_pin_list *pin = irq_2_pin_ptr;
if (!pin)
panic("can not get more irq_2_pin\n");
irq_2_pin_ptr = pin->next;
pin->next = NULL;
return pin;
}
struct irq_cfg {
struct irq_pin_list *irq_2_pin;
cpumask_t domain;
cpumask_t old_domain;
unsigned move_cleanup_count;
u8 vector;
u8 move_in_progress : 1;
};
/* irq_cfg is indexed by the sum of all RTEs in all I/O APICs. */
#ifdef CONFIG_SPARSE_IRQ
static struct irq_cfg irq_cfgx[] = {
#else
static struct irq_cfg irq_cfgx[NR_IRQS] = {
#endif
[0] = { .domain = CPU_MASK_ALL, .vector = IRQ0_VECTOR, },
[1] = { .domain = CPU_MASK_ALL, .vector = IRQ1_VECTOR, },
[2] = { .domain = CPU_MASK_ALL, .vector = IRQ2_VECTOR, },
[3] = { .domain = CPU_MASK_ALL, .vector = IRQ3_VECTOR, },
[4] = { .domain = CPU_MASK_ALL, .vector = IRQ4_VECTOR, },
[5] = { .domain = CPU_MASK_ALL, .vector = IRQ5_VECTOR, },
[6] = { .domain = CPU_MASK_ALL, .vector = IRQ6_VECTOR, },
[7] = { .domain = CPU_MASK_ALL, .vector = IRQ7_VECTOR, },
[8] = { .domain = CPU_MASK_ALL, .vector = IRQ8_VECTOR, },
[9] = { .domain = CPU_MASK_ALL, .vector = IRQ9_VECTOR, },
[10] = { .domain = CPU_MASK_ALL, .vector = IRQ10_VECTOR, },
[11] = { .domain = CPU_MASK_ALL, .vector = IRQ11_VECTOR, },
[12] = { .domain = CPU_MASK_ALL, .vector = IRQ12_VECTOR, },
[13] = { .domain = CPU_MASK_ALL, .vector = IRQ13_VECTOR, },
[14] = { .domain = CPU_MASK_ALL, .vector = IRQ14_VECTOR, },
[15] = { .domain = CPU_MASK_ALL, .vector = IRQ15_VECTOR, },
};
void __init arch_early_irq_init(void)
{
struct irq_cfg *cfg;
struct irq_desc *desc;
int count;
int i;
cfg = irq_cfgx;
count = ARRAY_SIZE(irq_cfgx);
for (i = 0; i < count; i++) {
desc = irq_to_desc(i);
desc->chip_data = &cfg[i];
}
}
#ifdef CONFIG_SPARSE_IRQ
static struct irq_cfg *irq_cfg(unsigned int irq)
{
struct irq_cfg *cfg = NULL;
struct irq_desc *desc;
desc = irq_to_desc(irq);
if (desc)
cfg = desc->chip_data;
return cfg;
}
static struct irq_cfg *get_one_free_irq_cfg(int cpu)
{
struct irq_cfg *cfg;
int node;
node = cpu_to_node(cpu);
cfg = kzalloc_node(sizeof(*cfg), GFP_ATOMIC, node);
printk(KERN_DEBUG " alloc irq_cfg on cpu %d node %d\n", cpu, node);
return cfg;
}
void arch_init_chip_data(struct irq_desc *desc, int cpu)
{
struct irq_cfg *cfg;
cfg = desc->chip_data;
if (!cfg) {
desc->chip_data = get_one_free_irq_cfg(cpu);
if (!desc->chip_data) {
printk(KERN_ERR "can not alloc irq_cfg\n");
BUG_ON(1);
}
}
}
#else
static struct irq_cfg *irq_cfg(unsigned int irq)
{
return irq < nr_irqs ? irq_cfgx + irq : NULL;
}
#endif
struct io_apic {
unsigned int index;
unsigned int unused[3];
@ -397,16 +432,19 @@ static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t mask)
* shared ISA-space IRQs, so we have to support them. We are super
* fast in the common case, and fast for shared ISA-space IRQs.
*/
static void add_pin_to_irq(unsigned int irq, int apic, int pin)
static void add_pin_to_irq_cpu(unsigned int irq, int cpu, int apic, int pin)
{
struct irq_cfg *cfg;
struct irq_pin_list *entry;
struct irq_cfg *cfg = irq_cfg(irq);
/* first time to refer irq_cfg, so with new */
cfg = irq_cfg_alloc(irq);
entry = cfg->irq_2_pin;
if (!entry) {
entry = get_one_free_irq_2_pin();
entry = get_one_free_irq_2_pin(cpu);
if (!entry) {
printk(KERN_ERR "can not alloc irq_2_pin to add %d - %d\n",
apic, pin);
return;
}
cfg->irq_2_pin = entry;
entry->apic = apic;
entry->pin = pin;
@ -421,7 +459,7 @@ static void add_pin_to_irq(unsigned int irq, int apic, int pin)
entry = entry->next;
}
entry->next = get_one_free_irq_2_pin();
entry->next = get_one_free_irq_2_pin(cpu);
entry = entry->next;
entry->apic = apic;
entry->pin = pin;
@ -430,7 +468,7 @@ static void add_pin_to_irq(unsigned int irq, int apic, int pin)
/*
* Reroute an IRQ to a different pin.
*/
static void __init replace_pin_at_irq(unsigned int irq,
static void __init replace_pin_at_irq(unsigned int irq, int cpu,
int oldapic, int oldpin,
int newapic, int newpin)
{
@ -451,7 +489,7 @@ static void __init replace_pin_at_irq(unsigned int irq,
/* why? call replace before add? */
if (!replaced)
add_pin_to_irq(irq, newapic, newpin);
add_pin_to_irq_cpu(irq, cpu, newapic, newpin);
}
static inline void io_apic_modify_irq(unsigned int irq,
@ -1162,9 +1200,13 @@ void __setup_vector_irq(int cpu)
/* This function must be called with vector_lock held */
int irq, vector;
struct irq_cfg *cfg;
struct irq_desc *desc;
/* Mark the inuse vectors */
for_each_irq_cfg(irq, cfg) {
for_each_irq_desc(irq, desc) {
if (!desc)
continue;
cfg = desc->chip_data;
if (!cpu_isset(cpu, cfg->domain))
continue;
vector = cfg->vector;
@ -1356,6 +1398,8 @@ static void __init setup_IO_APIC_irqs(void)
{
int apic, pin, idx, irq;
int notcon = 0;
struct irq_desc *desc;
int cpu = boot_cpu_id;
apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
@ -1387,7 +1431,12 @@ static void __init setup_IO_APIC_irqs(void)
if (multi_timer_check(apic, irq))
continue;
#endif
add_pin_to_irq(irq, apic, pin);
desc = irq_to_desc_alloc_cpu(irq, cpu);
if (!desc) {
printk(KERN_INFO "can not get irq_desc for %d\n", irq);
continue;
}
add_pin_to_irq_cpu(irq, cpu, apic, pin);
setup_IO_APIC_irq(apic, pin, irq,
irq_trigger(idx), irq_polarity(idx));
@ -1448,6 +1497,7 @@ __apicdebuginit(void) print_IO_APIC(void)
union IO_APIC_reg_03 reg_03;
unsigned long flags;
struct irq_cfg *cfg;
struct irq_desc *desc;
unsigned int irq;
if (apic_verbosity == APIC_QUIET)
@ -1537,8 +1587,13 @@ __apicdebuginit(void) print_IO_APIC(void)
}
}
printk(KERN_DEBUG "IRQ to pin mappings:\n");
for_each_irq_cfg(irq, cfg) {
struct irq_pin_list *entry = cfg->irq_2_pin;
for_each_irq_desc(irq, desc) {
struct irq_pin_list *entry;
if (!desc)
continue;
cfg = desc->chip_data;
entry = cfg->irq_2_pin;
if (!entry)
continue;
printk(KERN_DEBUG "IRQ%d ", irq);
@ -2022,6 +2077,7 @@ static unsigned int startup_ioapic_irq(unsigned int irq)
{
int was_pending = 0;
unsigned long flags;
struct irq_cfg *cfg;
spin_lock_irqsave(&ioapic_lock, flags);
if (irq < 16) {
@ -2029,6 +2085,7 @@ static unsigned int startup_ioapic_irq(unsigned int irq)
if (i8259A_irq_pending(irq))
was_pending = 1;
}
cfg = irq_cfg(irq);
__unmask_IO_APIC_irq(irq);
spin_unlock_irqrestore(&ioapic_lock, flags);
@ -2178,6 +2235,9 @@ static void ir_irq_migration(struct work_struct *work)
struct irq_desc *desc;
for_each_irq_desc(irq, desc) {
if (!desc)
continue;
if (desc->status & IRQ_MOVE_PENDING) {
unsigned long flags;
@ -2229,6 +2289,9 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void)
struct irq_cfg *cfg;
irq = __get_cpu_var(vector_irq)[vector];
if (irq == -1)
continue;
desc = irq_to_desc(irq);
if (!desc)
continue;
@ -2430,8 +2493,12 @@ static inline void init_IO_APIC_traps(void)
* Also, we've got to be careful not to trash gate
* 0x80, because int 0x80 is hm, kind of importantish. ;)
*/
for_each_irq_cfg(irq, cfg) {
if (IO_APIC_IRQ(irq) && !cfg->vector) {
for_each_irq_desc(irq, desc) {
if (!desc)
continue;
cfg = desc->chip_data;
if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
/*
* Hmm.. We don't have an entry for this,
* so default to an old-fashioned 8259
@ -2439,13 +2506,11 @@ static inline void init_IO_APIC_traps(void)
*/
if (irq < 16)
make_8259A_irq(irq);
else {
desc = irq_to_desc(irq);
else
/* Strange. Oh, well.. */
desc->chip = &no_irq_chip;
}
}
}
}
/*
@ -2654,7 +2719,7 @@ static inline void __init check_timer(void)
* Ok, does IRQ0 through the IOAPIC work?
*/
if (no_pin1) {
add_pin_to_irq(0, apic1, pin1);
add_pin_to_irq_cpu(0, boot_cpu_id, apic1, pin1);
setup_timer_IRQ0_pin(apic1, pin1, cfg->vector);
}
unmask_IO_APIC_irq(0);
@ -2683,7 +2748,7 @@ static inline void __init check_timer(void)
/*
* legacy devices should be connected to IO APIC #0
*/
replace_pin_at_irq(0, apic1, pin1, apic2, pin2);
replace_pin_at_irq(0, boot_cpu_id, apic1, pin1, apic2, pin2);
setup_timer_IRQ0_pin(apic2, pin2, cfg->vector);
unmask_IO_APIC_irq(0);
enable_8259A_irq(0);
@ -2902,21 +2967,25 @@ unsigned int create_irq_nr(unsigned int irq_want)
unsigned int irq;
unsigned int new;
unsigned long flags;
struct irq_cfg *cfg_new;
irq_want = nr_irqs - 1;
struct irq_cfg *cfg_new = NULL;
int cpu = boot_cpu_id;
struct irq_desc *desc_new = NULL;
irq = 0;
spin_lock_irqsave(&vector_lock, flags);
for (new = irq_want; new > 0; new--) {
if (platform_legacy_irq(new))
continue;
cfg_new = irq_cfg(new);
if (cfg_new && cfg_new->vector != 0)
desc_new = irq_to_desc_alloc_cpu(new, cpu);
if (!desc_new) {
printk(KERN_INFO "can not get irq_desc for %d\n", new);
continue;
}
cfg_new = desc_new->chip_data;
if (cfg_new->vector != 0)
continue;
/* check if need to create one */
if (!cfg_new)
cfg_new = irq_cfg_alloc(new);
if (__assign_irq_vector(new, TARGET_CPUS) == 0)
irq = new;
break;
@ -2925,6 +2994,9 @@ unsigned int create_irq_nr(unsigned int irq_want)
if (irq > 0) {
dynamic_irq_init(irq);
/* restore it, in case dynamic_irq_init clear it */
if (desc_new)
desc_new->chip_data = cfg_new;
}
return irq;
}
@ -2944,8 +3016,16 @@ int create_irq(void)
void destroy_irq(unsigned int irq)
{
unsigned long flags;
struct irq_cfg *cfg;
struct irq_desc *desc;
/* store it, in case dynamic_irq_cleanup clear it */
desc = irq_to_desc(irq);
cfg = desc->chip_data;
dynamic_irq_cleanup(irq);
/* connect back irq_cfg */
if (desc)
desc->chip_data = cfg;
#ifdef CONFIG_INTR_REMAP
free_irte(irq);
@ -3195,26 +3275,13 @@ static int setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc, int irq)
return 0;
}
static unsigned int build_irq_for_pci_dev(struct pci_dev *dev)
{
unsigned int irq;
irq = dev->bus->number;
irq <<= 8;
irq |= dev->devfn;
irq <<= 12;
return irq;
}
int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc)
{
unsigned int irq;
int ret;
unsigned int irq_want;
irq_want = build_irq_for_pci_dev(dev) + 0x100;
irq_want = nr_irqs - 1;
irq = create_irq_nr(irq_want);
if (irq == 0)
return -1;
@ -3228,7 +3295,7 @@ int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
goto error;
no_ir:
#endif
ret = setup_msi_irq(dev, desc, irq);
ret = setup_msi_irq(dev, msidesc, irq);
if (ret < 0) {
destroy_irq(irq);
return ret;
@ -3246,7 +3313,7 @@ int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
unsigned int irq;
int ret, sub_handle;
struct msi_desc *desc;
struct msi_desc *msidesc;
unsigned int irq_want;
#ifdef CONFIG_INTR_REMAP
@ -3254,10 +3321,11 @@ int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
int index = 0;
#endif
irq_want = build_irq_for_pci_dev(dev) + 0x100;
irq_want = nr_irqs - 1;
sub_handle = 0;
list_for_each_entry(desc, &dev->msi_list, list) {
irq = create_irq_nr(irq_want--);
list_for_each_entry(msidesc, &dev->msi_list, list) {
irq = create_irq_nr(irq_want);
irq_want--;
if (irq == 0)
return -1;
#ifdef CONFIG_INTR_REMAP
@ -3289,7 +3357,7 @@ int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
}
no_ir:
#endif
ret = setup_msi_irq(dev, desc, irq);
ret = setup_msi_irq(dev, msidesc, irq);
if (ret < 0)
goto error;
sub_handle++;
@ -3707,17 +3775,29 @@ int __init io_apic_get_version(int ioapic)
int io_apic_set_pci_routing (int ioapic, int pin, int irq, int triggering, int polarity)
{
struct irq_desc *desc;
struct irq_cfg *cfg;
int cpu = boot_cpu_id;
if (!IO_APIC_IRQ(irq)) {
apic_printk(APIC_QUIET,KERN_ERR "IOAPIC[%d]: Invalid reference to IRQ 0\n",
ioapic);
return -EINVAL;
}
desc = irq_to_desc_alloc_cpu(irq, cpu);
if (!desc) {
printk(KERN_INFO "can not get irq_desc %d\n", irq);
return 0;
}
/*
* IRQs < 16 are already in the irq_2_pin[] map
*/
if (irq >= 16)
add_pin_to_irq(irq, ioapic, pin);
if (irq >= 16) {
cfg = desc->chip_data;
add_pin_to_irq_cpu(irq, cpu, ioapic, pin);
}
setup_IO_APIC_irq(ioapic, pin, irq, triggering, polarity);
@ -3773,7 +3853,8 @@ void __init setup_ioapic_dest(void)
* when you have too many devices, because at that time only boot
* cpu is online.
*/
cfg = irq_cfg(irq);
desc = irq_to_desc(irq);
cfg = desc->chip_data;
if (!cfg->vector) {
setup_IO_APIC_irq(ioapic, pin, irq,
irq_trigger(irq_entry),
@ -3785,7 +3866,6 @@ void __init setup_ioapic_dest(void)
/*
* Honour affinities which have been set in early boot
*/
desc = irq_to_desc(irq);
if (desc->status &
(IRQ_NO_BALANCING | IRQ_AFFINITY_SET))
mask = desc->affinity;
@ -3846,7 +3926,6 @@ void __init ioapic_init_mappings(void)
struct resource *ioapic_res;
int i;
irq_2_pin_init();
ioapic_res = ioapic_setup_resources();
for (i = 0; i < nr_ioapics; i++) {
if (smp_found_config) {

3
arch/x86/kernel/irq.c
Просмотреть файл

@ -118,6 +118,9 @@ int show_interrupts(struct seq_file *p, void *v)
}
desc = irq_to_desc(i);
if (!desc)
return 0;
spin_lock_irqsave(&desc->lock, flags);
#ifndef CONFIG_SMP
any_count = kstat_irqs(i);

2
arch/x86/kernel/irq_32.c
Просмотреть файл

@ -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;

2
arch/x86/kernel/irq_64.c
Просмотреть файл

@ -94,6 +94,8 @@ void fixup_irqs(cpumask_t map)
int break_affinity = 0;
int set_affinity = 1;
if (!desc)
continue;
if (irq == 2)
continue;

1
arch/x86/kernel/irqinit_32.c
Просмотреть файл

@ -69,7 +69,6 @@ void __init init_ISA_irqs (void)
* 16 old-style INTA-cycle interrupts:
*/
for (i = 0; i < 16; i++) {
/* first time call this irq_desc */
struct irq_desc *desc = irq_to_desc(i);
desc->status = IRQ_DISABLED;

1
arch/x86/kernel/irqinit_64.c
Просмотреть файл

@ -143,7 +143,6 @@ void __init init_ISA_irqs(void)
init_8259A(0);
for (i = 0; i < 16; i++) {
/* first time call this irq_desc */
struct irq_desc *desc = irq_to_desc(i);
desc->status = IRQ_DISABLED;

22
drivers/char/random.c
Просмотреть файл

@ -558,23 +558,9 @@ struct timer_rand_state {
unsigned dont_count_entropy:1;
};
static struct timer_rand_state *irq_timer_state[NR_IRQS];
static struct timer_rand_state *get_timer_rand_state(unsigned int irq)
{
if (irq >= nr_irqs)
return NULL;
return irq_timer_state[irq];
}
static void set_timer_rand_state(unsigned int irq, struct timer_rand_state *state)
{
if (irq >= nr_irqs)
return;
irq_timer_state[irq] = state;
}
#ifndef CONFIG_SPARSE_IRQ
struct timer_rand_state *irq_timer_state[NR_IRQS];
#endif
static struct timer_rand_state input_timer_state;
@ -933,8 +919,10 @@ void rand_initialize_irq(int irq)
{
struct timer_rand_state *state;
#ifndef CONFIG_SPARSE_IRQ
if (irq >= nr_irqs)
return;
#endif
state = get_timer_rand_state(irq);

76
drivers/pci/intr_remapping.c
Просмотреть файл

@ -19,17 +19,75 @@ struct irq_2_iommu {
u8 irte_mask;
};
static struct irq_2_iommu irq_2_iommuX[NR_IRQS];
#ifdef CONFIG_SPARSE_IRQ
static struct irq_2_iommu *get_one_free_irq_2_iommu(int cpu)
{
struct irq_2_iommu *iommu;
int node;
node = cpu_to_node(cpu);
iommu = kzalloc_node(sizeof(*iommu), GFP_ATOMIC, node);
printk(KERN_DEBUG "alloc irq_2_iommu on cpu %d node %d\n", cpu, node);
return iommu;
}
static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
{
return (irq < nr_irqs) ? irq_2_iommuX + irq : NULL;
struct irq_desc *desc;
desc = irq_to_desc(irq);
if (WARN_ON_ONCE(!desc))
return NULL;
return desc->irq_2_iommu;
}
static struct irq_2_iommu *irq_2_iommu_alloc_cpu(unsigned int irq, int cpu)
{
struct irq_desc *desc;
struct irq_2_iommu *irq_iommu;
/*
* alloc irq desc if not allocated already.
*/
desc = irq_to_desc_alloc_cpu(irq, cpu);
if (!desc) {
printk(KERN_INFO "can not get irq_desc for %d\n", irq);
return NULL;
}
irq_iommu = desc->irq_2_iommu;
if (!irq_iommu)
desc->irq_2_iommu = get_one_free_irq_2_iommu(cpu);
return desc->irq_2_iommu;
}
static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq)
{
return irq_2_iommu_alloc_cpu(irq, boot_cpu_id);
}
#else /* !CONFIG_SPARSE_IRQ */
static struct irq_2_iommu irq_2_iommuX[NR_IRQS];
static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
{
if (irq < nr_irqs)
return &irq_2_iommuX[irq];
return NULL;
}
static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq)
{
return irq_2_iommu(irq);
}
#endif
static DEFINE_SPINLOCK(irq_2_ir_lock);
@ -86,9 +144,11 @@ int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
if (!count)
return -1;
#ifndef CONFIG_SPARSE_IRQ
/* protect irq_2_iommu_alloc later */
if (irq >= nr_irqs)
return -1;
#endif
/*
* start the IRTE search from index 0.
@ -130,6 +190,12 @@ int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
table->base[i].present = 1;
irq_iommu = irq_2_iommu_alloc(irq);
if (!irq_iommu) {
spin_unlock(&irq_2_ir_lock);
printk(KERN_ERR "can't allocate irq_2_iommu\n");
return -1;
}
irq_iommu->iommu = iommu;
irq_iommu->irte_index = index;
irq_iommu->sub_handle = 0;
@ -177,6 +243,12 @@ int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
irq_iommu = irq_2_iommu_alloc(irq);
if (!irq_iommu) {
spin_unlock(&irq_2_ir_lock);
printk(KERN_ERR "can't allocate irq_2_iommu\n");
return -1;
}
irq_iommu->iommu = iommu;
irq_iommu->irte_index = index;
irq_iommu->sub_handle = subhandle;

12
drivers/xen/events.c
Просмотреть файл

@ -141,8 +141,12 @@ static void init_evtchn_cpu_bindings(void)
int i;
/* By default all event channels notify CPU#0. */
for_each_irq_desc(i, desc)
for_each_irq_desc(i, desc) {
if (!desc)
continue;
desc->affinity = cpumask_of_cpu(0);
}
#endif
memset(cpu_evtchn, 0, sizeof(cpu_evtchn));
@ -231,7 +235,7 @@ static int find_unbound_irq(void)
int irq;
/* Only allocate from dynirq range */
for_each_irq_nr(irq)
for (irq = 0; irq < nr_irqs; irq++)
if (irq_bindcount[irq] == 0)
break;
@ -792,7 +796,7 @@ void xen_irq_resume(void)
mask_evtchn(evtchn);
/* No IRQ <-> event-channel mappings. */
for_each_irq_nr(irq)
for (irq = 0; irq < nr_irqs; irq++)
irq_info[irq].evtchn = 0; /* zap event-channel binding */
for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
@ -824,7 +828,7 @@ void __init xen_init_IRQ(void)
mask_evtchn(i);
/* Dynamic IRQ space is currently unbound. Zero the refcnts. */
for_each_irq_nr(i)
for (i = 0; i < nr_irqs; i++)
irq_bindcount[i] = 0;
irq_ctx_init(smp_processor_id());

13
fs/proc/stat.c
Просмотреть файл

@ -27,6 +27,7 @@ static int show_stat(struct seq_file *p, void *v)
u64 sum = 0;
struct timespec boottime;
unsigned int per_irq_sum;
struct irq_desc *desc;
user = nice = system = idle = iowait =
irq = softirq = steal = cputime64_zero;
@ -44,10 +45,11 @@ static int show_stat(struct seq_file *p, void *v)
softirq = cputime64_add(softirq, kstat_cpu(i).cpustat.softirq);
steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal);
guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest);
for_each_irq_nr(j)
for_each_irq_desc(j, desc) {
if (!desc)
continue;
sum += kstat_irqs_cpu(j, i);
}
sum += arch_irq_stat_cpu(i);
}
sum += arch_irq_stat();
@ -90,11 +92,14 @@ static int show_stat(struct seq_file *p, void *v)
seq_printf(p, "intr %llu", (unsigned long long)sum);
/* sum again ? it could be updated? */
for_each_irq_nr(j) {
for (j = 0; j < NR_IRQS; j++) {
desc = irq_to_desc(j);
per_irq_sum = 0;
if (desc) {
for_each_possible_cpu(i)
per_irq_sum += kstat_irqs_cpu(j, i);
}
seq_printf(p, " %u", per_irq_sum);
}

2
include/linux/interrupt.h
Просмотреть файл

@ -18,6 +18,8 @@
#include <asm/ptrace.h>
#include <asm/system.h>
extern int nr_irqs;
/*
* These correspond to the IORESOURCE_IRQ_* defines in
* linux/ioport.h to select the interrupt line behaviour. When

54
include/linux/irq.h
Просмотреть файл

@ -129,6 +129,8 @@ struct irq_chip {
const char *typename;
};
struct timer_rand_state;
struct irq_2_iommu;
/**
* struct irq_desc - interrupt descriptor
* @irq: interrupt number for this descriptor
@ -154,6 +156,13 @@ struct irq_chip {
*/
struct irq_desc {
unsigned int irq;
#ifdef CONFIG_SPARSE_IRQ
struct timer_rand_state *timer_rand_state;
unsigned int *kstat_irqs;
# ifdef CONFIG_INTR_REMAP
struct irq_2_iommu *irq_2_iommu;
# endif
#endif
irq_flow_handler_t handle_irq;
struct irq_chip *chip;
struct msi_desc *msi_desc;
@ -181,13 +190,51 @@ struct irq_desc {
const char *name;
} ____cacheline_internodealigned_in_smp;
extern void early_irq_init(void);
extern void arch_early_irq_init(void);
extern void arch_init_chip_data(struct irq_desc *desc, int cpu);
extern void arch_init_copy_chip_data(struct irq_desc *old_desc,
struct irq_desc *desc, int cpu);
extern void arch_free_chip_data(struct irq_desc *old_desc, struct irq_desc *desc);
#ifndef CONFIG_SPARSE_IRQ
extern struct irq_desc irq_desc[NR_IRQS];
static inline struct irq_desc *irq_to_desc(unsigned int irq)
{
return (irq < nr_irqs) ? irq_desc + irq : NULL;
return (irq < NR_IRQS) ? irq_desc + irq : NULL;
}
static inline struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
{
return irq_to_desc(irq);
}
#ifdef CONFIG_GENERIC_HARDIRQS
# define for_each_irq_desc(irq, desc) \
for (irq = 0, desc = irq_desc; irq < nr_irqs; irq++, desc++)
# define for_each_irq_desc_reverse(irq, desc) \
for (irq = nr_irqs - 1, desc = irq_desc + (nr_irqs - 1); \
irq >= 0; irq--, desc--)
#endif
#else
extern struct irq_desc *irq_to_desc(unsigned int irq);
extern struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu);
extern struct irq_desc *move_irq_desc(struct irq_desc *old_desc, int cpu);
# define for_each_irq_desc(irq, desc) \
for (irq = 0, desc = irq_to_desc(irq); irq < nr_irqs; irq++, desc = irq_to_desc(irq))
# define for_each_irq_desc_reverse(irq, desc) \
for (irq = nr_irqs - 1, desc = irq_to_desc(irq); irq >= 0; irq--, desc = irq_to_desc(irq))
#define kstat_irqs_this_cpu(DESC) \
((DESC)->kstat_irqs[smp_processor_id()])
#define kstat_incr_irqs_this_cpu(irqno, DESC) \
((DESC)->kstat_irqs[smp_processor_id()]++)
#endif
/*
* Migration helpers for obsolete names, they will go away:
@ -380,6 +427,11 @@ extern int set_irq_msi(unsigned int irq, struct msi_desc *entry);
#define get_irq_data(irq) (irq_to_desc(irq)->handler_data)
#define get_irq_msi(irq) (irq_to_desc(irq)->msi_desc)
#define get_irq_desc_chip(desc) ((desc)->chip)
#define get_irq_desc_chip_data(desc) ((desc)->chip_data)
#define get_irq_desc_data(desc) ((desc)->handler_data)
#define get_irq_desc_msi(desc) ((desc)->msi_desc)
#endif /* CONFIG_GENERIC_HARDIRQS */
#endif /* !CONFIG_S390 */

14
include/linux/irqnr.h
Просмотреть файл

@ -7,18 +7,10 @@
# define for_each_irq_desc(irq, desc) \
for (irq = 0; irq < nr_irqs; irq++)
#else
extern int nr_irqs;
# define for_each_irq_desc(irq, desc) \
for (irq = 0, desc = irq_desc; irq < nr_irqs; irq++, desc++)
# define for_each_irq_desc_reverse(irq, desc) \
for (irq = nr_irqs - 1, desc = irq_desc + (nr_irqs - 1); \
irq >= 0; irq--, desc--)
static inline early_sparse_irq_init(void)
{
}
#endif
#define for_each_irq_nr(irq) \
for (irq = 0; irq < nr_irqs; irq++)
#endif

12
include/linux/kernel_stat.h
Просмотреть файл

@ -28,7 +28,9 @@ struct cpu_usage_stat {
struct kernel_stat {
struct cpu_usage_stat cpustat;
#ifndef CONFIG_SPARSE_IRQ
unsigned int irqs[NR_IRQS];
#endif
};
DECLARE_PER_CPU(struct kernel_stat, kstat);
@ -39,6 +41,10 @@ DECLARE_PER_CPU(struct kernel_stat, kstat);
extern unsigned long long nr_context_switches(void);
#ifndef CONFIG_SPARSE_IRQ
#define kstat_irqs_this_cpu(irq) \
(kstat_this_cpu.irqs[irq])
struct irq_desc;
static inline void kstat_incr_irqs_this_cpu(unsigned int irq,
@ -46,11 +52,17 @@ static inline void kstat_incr_irqs_this_cpu(unsigned int irq,
{
kstat_this_cpu.irqs[irq]++;
}
#endif
#ifndef CONFIG_SPARSE_IRQ
static inline unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
{
return kstat_cpu(cpu).irqs[irq];
}
#else
extern unsigned int kstat_irqs_cpu(unsigned int irq, int cpu);
#endif
/*
* Number of interrupts per specific IRQ source, since bootup

51
include/linux/random.h
Просмотреть файл

@ -44,6 +44,57 @@ struct rand_pool_info {
extern void rand_initialize_irq(int irq);
struct timer_rand_state;
#ifndef CONFIG_SPARSE_IRQ
extern struct timer_rand_state *irq_timer_state[];
extern int nr_irqs;
static inline struct timer_rand_state *get_timer_rand_state(unsigned int irq)
{
if (irq >= nr_irqs)
return NULL;
return irq_timer_state[irq];
}
static inline void set_timer_rand_state(unsigned int irq, struct timer_rand_state *state)
{
if (irq >= nr_irqs)
return;
irq_timer_state[irq] = state;
}
#else
#include <linux/irq.h>
static inline struct timer_rand_state *get_timer_rand_state(unsigned int irq)
{
struct irq_desc *desc;
desc = irq_to_desc(irq);
if (!desc)
return NULL;
return desc->timer_rand_state;
}
static inline void set_timer_rand_state(unsigned int irq, struct timer_rand_state *state)
{
struct irq_desc *desc;
desc = irq_to_desc(irq);
if (!desc)
return;
desc->timer_rand_state = state;
}
#endif
extern void add_input_randomness(unsigned int type, unsigned int code,
unsigned int value);
extern void add_interrupt_randomness(int irq);

11
init/main.c
Просмотреть файл

@ -539,6 +539,15 @@ void __init __weak thread_info_cache_init(void)
{
}
void __init __weak arch_early_irq_init(void)
{
}
void __init __weak early_irq_init(void)
{
arch_early_irq_init();
}
asmlinkage void __init start_kernel(void)
{
char * command_line;
@ -603,6 +612,8 @@ asmlinkage void __init start_kernel(void)
sort_main_extable();
trap_init();
rcu_init();
/* init some links before init_ISA_irqs() */
early_irq_init();
init_IRQ();
pidhash_init();
init_timers();

15
kernel/irq/autoprobe.c
Просмотреть файл

@ -40,6 +40,9 @@ unsigned long probe_irq_on(void)
* flush such a longstanding irq before considering it as spurious.
*/
for_each_irq_desc_reverse(i, desc) {
if (!desc)
continue;
spin_lock_irq(&desc->lock);
if (!desc->action && !(desc->status & IRQ_NOPROBE)) {
/*
@ -68,6 +71,9 @@ unsigned long probe_irq_on(void)
* happened in the previous stage, it may have masked itself)
*/
for_each_irq_desc_reverse(i, desc) {
if (!desc)
continue;
spin_lock_irq(&desc->lock);
if (!desc->action && !(desc->status & IRQ_NOPROBE)) {
desc->status |= IRQ_AUTODETECT | IRQ_WAITING;
@ -86,6 +92,9 @@ unsigned long probe_irq_on(void)
* Now filter out any obviously spurious interrupts
*/
for_each_irq_desc(i, desc) {
if (!desc)
continue;
spin_lock_irq(&desc->lock);
status = desc->status;
@ -124,6 +133,9 @@ unsigned int probe_irq_mask(unsigned long val)
int i;
for_each_irq_desc(i, desc) {
if (!desc)
continue;
spin_lock_irq(&desc->lock);
status = desc->status;
@ -166,6 +178,9 @@ int probe_irq_off(unsigned long val)
unsigned int status;
for_each_irq_desc(i, desc) {
if (!desc)
continue;
spin_lock_irq(&desc->lock);
status = desc->status;

3
kernel/irq/chip.c
Просмотреть файл

@ -24,9 +24,10 @@
*/
void dynamic_irq_init(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
struct irq_desc *desc;
unsigned long flags;
desc = irq_to_desc(irq);
if (!desc) {
WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
return;

181
kernel/irq/handle.c
Просмотреть файл

@ -15,9 +15,16 @@
#include <linux/random.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/rculist.h>
#include <linux/hash.h>
#include "internals.h"
/*
* lockdep: we want to handle all irq_desc locks as a single lock-class:
*/
static struct lock_class_key irq_desc_lock_class;
/**
* handle_bad_irq - handle spurious and unhandled irqs
* @irq: the interrupt number
@ -49,6 +56,155 @@ void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
int nr_irqs = NR_IRQS;
EXPORT_SYMBOL_GPL(nr_irqs);
void __init __attribute__((weak)) arch_early_irq_init(void)
{
}
#ifdef CONFIG_SPARSE_IRQ
static struct irq_desc irq_desc_init = {
.irq = -1,
.status = IRQ_DISABLED,
.chip = &no_irq_chip,
.handle_irq = handle_bad_irq,
.depth = 1,
.lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
#ifdef CONFIG_SMP
.affinity = CPU_MASK_ALL
#endif
};
static void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr)
{
unsigned long bytes;
char *ptr;
int node;
/* Compute how many bytes we need per irq and allocate them */
bytes = nr * sizeof(unsigned int);
node = cpu_to_node(cpu);
ptr = kzalloc_node(bytes, GFP_ATOMIC, node);
printk(KERN_DEBUG " alloc kstat_irqs on cpu %d node %d\n", cpu, node);
if (ptr)
desc->kstat_irqs = (unsigned int *)ptr;
}
void __attribute__((weak)) arch_init_chip_data(struct irq_desc *desc, int cpu)
{
}
static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
{
memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
desc->irq = irq;
#ifdef CONFIG_SMP
desc->cpu = cpu;
#endif
lockdep_set_class(&desc->lock, &irq_desc_lock_class);
init_kstat_irqs(desc, cpu, nr_cpu_ids);
if (!desc->kstat_irqs) {
printk(KERN_ERR "can not alloc kstat_irqs\n");
BUG_ON(1);
}
arch_init_chip_data(desc, cpu);
}
/*
* Protect the sparse_irqs:
*/
static DEFINE_SPINLOCK(sparse_irq_lock);
struct irq_desc *irq_desc_ptrs[NR_IRQS] __read_mostly;
static struct irq_desc irq_desc_legacy[16] __cacheline_aligned_in_smp = {
[0 ... 15] = {
.irq = -1,
.status = IRQ_DISABLED,
.chip = &no_irq_chip,
.handle_irq = handle_bad_irq,
.depth = 1,
.lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
#ifdef CONFIG_SMP
.affinity = CPU_MASK_ALL
#endif
}
};
/* FIXME: use bootmem alloc ...*/
static unsigned int kstat_irqs_legacy[16][NR_CPUS];
void __init early_irq_init(void)
{
struct irq_desc *desc;
int legacy_count;
int i;
desc = irq_desc_legacy;
legacy_count = ARRAY_SIZE(irq_desc_legacy);
for (i = 0; i < legacy_count; i++) {
desc[i].irq = i;
desc[i].kstat_irqs = kstat_irqs_legacy[i];
irq_desc_ptrs[i] = desc + i;
}
for (i = legacy_count; i < NR_IRQS; i++)
irq_desc_ptrs[i] = NULL;
arch_early_irq_init();
}
struct irq_desc *irq_to_desc(unsigned int irq)
{
return (irq < NR_IRQS) ? irq_desc_ptrs[irq] : NULL;
}
struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
{
struct irq_desc *desc;
unsigned long flags;
int node;
if (irq >= NR_IRQS) {
printk(KERN_WARNING "irq >= NR_IRQS in irq_to_desc_alloc: %d %d\n",
irq, NR_IRQS);
WARN_ON(1);
return NULL;
}
desc = irq_desc_ptrs[irq];
if (desc)
return desc;
spin_lock_irqsave(&sparse_irq_lock, flags);
/* We have to check it to avoid races with another CPU */
desc = irq_desc_ptrs[irq];
if (desc)
goto out_unlock;
node = cpu_to_node(cpu);
desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
printk(KERN_DEBUG " alloc irq_desc for %d on cpu %d node %d\n",
irq, cpu, node);
if (!desc) {
printk(KERN_ERR "can not alloc irq_desc\n");
BUG_ON(1);
}
init_one_irq_desc(irq, desc, cpu);
irq_desc_ptrs[irq] = desc;
out_unlock:
spin_unlock_irqrestore(&sparse_irq_lock, flags);
return desc;
}
#else
struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
[0 ... NR_IRQS-1] = {
.status = IRQ_DISABLED,
@ -62,6 +218,8 @@ struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
}
};
#endif
/*
* What should we do if we get a hw irq event on an illegal vector?
* Each architecture has to answer this themself.
@ -261,17 +419,28 @@ out:
#ifdef CONFIG_TRACE_IRQFLAGS
/*
* lockdep: we want to handle all irq_desc locks as a single lock-class:
*/
static struct lock_class_key irq_desc_lock_class;
void early_init_irq_lock_class(void)
{
#ifndef CONFIG_SPARSE_IRQ
struct irq_desc *desc;
int i;
for_each_irq_desc(i, desc)
for_each_irq_desc(i, desc) {
if (!desc)
continue;
lockdep_set_class(&desc->lock, &irq_desc_lock_class);
}
#endif
}
#endif
#ifdef CONFIG_SPARSE_IRQ
unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
{
struct irq_desc *desc = irq_to_desc(irq);
return desc->kstat_irqs[cpu];
}
#endif
EXPORT_SYMBOL(kstat_irqs_cpu);

6
kernel/irq/proc.c
Просмотреть файл

@ -243,7 +243,11 @@ void init_irq_proc(void)
/*
* Create entries for all existing IRQs.
*/
for_each_irq_desc(irq, desc)
for_each_irq_desc(irq, desc) {
if (!desc)
continue;
register_irq_proc(irq, desc);
}
}

5
kernel/irq/spurious.c
Просмотреть файл

@ -91,6 +91,9 @@ static int misrouted_irq(int irq)
int i, ok = 0;
for_each_irq_desc(i, desc) {
if (!desc)
continue;
if (!i)
continue;
@ -112,6 +115,8 @@ static void poll_spurious_irqs(unsigned long dummy)
for_each_irq_desc(i, desc) {
unsigned int status;
if (!desc)
continue;
if (!i)
continue;