From 2c6927a38f65b53b62f86158fba29a068c4e8b6a Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Tue, 19 Aug 2008 20:50:11 -0700 Subject: [PATCH] irq: replace loop with nr_irqs with for_each_irq_desc There are a handful of loops that go from 0 to nr_irqs and use get_irq_desc() on them. These would allocate all the irq_desc entries, regardless of the need for them. Use the smarter for_each_irq_desc() iterator that will only iterate over the present ones. v2: make sure arch without GENERIC_HARDIRQS work too Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- arch/x86/kernel/io_apic_64.c | 6 +++--- arch/x86/kernel/irq_64.c | 5 ++--- arch/x86/kernel/irqinit_64.c | 17 +++++------------ include/linux/irq.h | 7 +++++++ kernel/irq/internals.h | 4 ++-- kernel/irq/manage.c | 2 +- kernel/irq/proc.c | 10 +++++----- 7 files changed, 25 insertions(+), 26 deletions(-) diff --git a/arch/x86/kernel/io_apic_64.c b/arch/x86/kernel/io_apic_64.c index 51ef7eb75f2..708be9724da 100644 --- a/arch/x86/kernel/io_apic_64.c +++ b/arch/x86/kernel/io_apic_64.c @@ -1871,10 +1871,10 @@ unmask: static void ir_irq_migration(struct work_struct *work) { - int irq; + unsigned int irq; + struct irq_desc *desc; - for (irq = 0; irq < nr_irqs; irq++) { - struct irq_desc *desc = irq_to_desc(irq); + for_each_irq_desc(irq, desc) { if (desc->status & IRQ_MOVE_PENDING) { unsigned long flags; diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index 4a0a4eb44dc..b3cf55e325f 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -224,17 +224,16 @@ void fixup_irqs(cpumask_t map) { unsigned int irq; static int warned; + struct irq_desc *desc; - for (irq = 0; irq < nr_irqs; irq++) { + for_each_irq_desc(irq, desc) { cpumask_t mask; int break_affinity = 0; int set_affinity = 1; - struct irq_desc *desc; if (irq == 2) continue; - desc = irq_to_desc(irq); /* interrupt's are disabled at this point */ spin_lock(&desc->lock); diff --git a/arch/x86/kernel/irqinit_64.c b/arch/x86/kernel/irqinit_64.c index 0744b49b4d1..cd9f42d028d 100644 --- a/arch/x86/kernel/irqinit_64.c +++ b/arch/x86/kernel/irqinit_64.c @@ -142,25 +142,18 @@ void __init init_ISA_irqs(void) init_bsp_APIC(); init_8259A(0); - for (i = 0; i < nr_irqs; i++) { + for (i = 0; i < 16; i++) { struct irq_desc *desc = irq_to_desc(i); desc->status = IRQ_DISABLED; desc->action = NULL; desc->depth = 1; - if (i < 16) { - /* - * 16 old-style INTA-cycle interrupts: - */ - set_irq_chip_and_handler_name(i, &i8259A_chip, + /* + * 16 old-style INTA-cycle interrupts: + */ + set_irq_chip_and_handler_name(i, &i8259A_chip, handle_level_irq, "XT"); - } else { - /* - * 'high' PCI IRQs filled in on demand - */ - desc->chip = &no_irq_chip; - } } } diff --git a/include/linux/irq.h b/include/linux/irq.h index c9ffef7c3b4..9de16ca8b8e 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -202,9 +202,16 @@ extern struct irq_desc irq_desc[NR_IRQS]; extern struct irq_desc *irq_desc; #endif +#ifdef CONFIG_GENERIC_HARDIRQS +#define for_each_irq_desc(irq, desc) \ + for (irq = 0, desc = irq_desc; irq < nr_irqs; irq++, desc = &irq_desc[irq]) +#endif + #else extern struct irq_desc *sparse_irqs; +#define for_each_irq_desc(irqX, desc) \ + for (desc = sparse_irqs, irqX = desc->irq; desc && irqX != -1U; desc = desc->next, irqX = desc ? desc->irq : -1U) #endif diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 422dd00c8bd..c9767e64198 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -14,11 +14,11 @@ extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, unsigned long flags); #ifdef CONFIG_PROC_FS -extern void register_irq_proc(unsigned int irq); +extern void register_irq_proc(unsigned int irq, struct irq_desc *desc); extern void register_handler_proc(unsigned int irq, struct irqaction *action); extern void unregister_handler_proc(unsigned int irq, struct irqaction *action); #else -static inline void register_irq_proc(unsigned int irq) { } +static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { } static inline void register_handler_proc(unsigned int irq, struct irqaction *action) { } static inline void unregister_handler_proc(unsigned int irq, diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index b5943e9f95a..5070f55fdc1 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -478,7 +478,7 @@ int setup_irq(unsigned int irq, struct irqaction *new) spin_unlock_irqrestore(&desc->lock, flags); new->irq = irq; - register_irq_proc(irq); + register_irq_proc(irq, desc); new->dir = NULL; register_handler_proc(irq, new); diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index c2f356c808f..bc0993d86c8 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -182,11 +182,10 @@ void register_handler_proc(unsigned int irq, struct irqaction *action) #define MAX_NAMELEN 10 -void register_irq_proc(unsigned int irq) +void register_irq_proc(unsigned int irq, struct irq_desc *desc) { char name [MAX_NAMELEN]; struct proc_dir_entry *entry; - struct irq_desc *desc = irq_to_desc(irq); if (!root_irq_dir || (desc->chip == &no_irq_chip) || desc->dir) return; @@ -230,7 +229,8 @@ void register_default_affinity_proc(void) void init_irq_proc(void) { - int i; + unsigned int irq; + struct irq_desc *desc; /* create /proc/irq */ root_irq_dir = proc_mkdir("irq", NULL); @@ -242,7 +242,7 @@ void init_irq_proc(void) /* * Create entries for all existing IRQs. */ - for (i = 0; i < nr_irqs; i++) - register_irq_proc(i); + for_each_irq_desc(irq, desc) + register_irq_proc(irq, desc); } -- 2.46.0