[Patch V4 16/42] x86, irq: introduce some helper utilities to improve readability

From: Jiang Liu
Date: Mon Jun 09 2014 - 04:19:50 EST


It also fixes an off by one bug in
if ((ioapic_idx > 0) && (irq > NR_IRQS_LEGACY))
It should be
if ((ioapic_idx > 0) && (irq >= NR_IRQS_LEGACY))

Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/io_apic.h | 2 ++
arch/x86/kernel/apic/io_apic.c | 29 ++++++++++++++++++++++-------
2 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/arch/x86/include/asm/io_apic.h b/arch/x86/include/asm/io_apic.h
index de3d8b04cf64..b775cf3622c3 100644
--- a/arch/x86/include/asm/io_apic.h
+++ b/arch/x86/include/asm/io_apic.h
@@ -171,6 +171,7 @@ extern u32 gsi_top;

extern int mp_find_ioapic(u32 gsi);
extern int mp_find_ioapic_pin(int ioapic, u32 gsi);
+extern u32 mp_pin_to_gsi(int ioapic, int pin);
extern void __init mp_register_ioapic(int id, u32 address, u32 gsi_base);
extern void __init pre_init_apic_IRQ0(void);

@@ -212,6 +213,7 @@ extern void io_apic_eoi(unsigned int apic, unsigned int vector);
static inline void ioapic_insert_resources(void) { }
#define gsi_top (NR_IRQS_LEGACY)
static inline int mp_find_ioapic(u32 gsi) { return 0; }
+static inline u32 mp_pin_to_gsi(int ioapic, int pin) { return UINT_MAX; }

struct io_apic_irq_attr;
static inline int io_apic_set_pci_routing(struct device *dev, int irq,
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 4ca3151d26f9..02faa7104aa5 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -117,6 +117,24 @@ struct mp_ioapic_gsi *mp_ioapic_gsi_routing(int ioapic_idx)
return &ioapics[ioapic_idx].gsi_config;
}

+static inline int mp_ioapic_pin_count(int ioapic)
+{
+ struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
+
+ return gsi_cfg->gsi_end - gsi_cfg->gsi_base + 1;
+}
+
+u32 mp_pin_to_gsi(int ioapic, int pin)
+{
+ return mp_ioapic_gsi_routing(ioapic)->gsi_base + pin;
+}
+
+/* Initialize all legacy IRQs and all pins on the first IOAPIC at boot */
+static inline int mp_init_irq_at_boot(int ioapic, int irq)
+{
+ return ioapic == 0 || (irq >= 0 && irq < NR_IRQS_LEGACY);
+}
+
int nr_ioapics;

/* The one past the highest gsi number used */
@@ -1367,8 +1385,7 @@ static void __init __io_apic_setup_irqs(unsigned int ioapic_idx)
continue;

irq = pin_2_irq(idx, ioapic_idx, pin);
-
- if ((ioapic_idx > 0) && (irq > NR_IRQS_LEGACY))
+ if (!mp_init_irq_at_boot(ioapic_idx, irq))
continue;

/*
@@ -1419,9 +1436,7 @@ void setup_IO_APIC_irq_extra(u32 gsi)
return;

irq = pin_2_irq(idx, ioapic_idx, pin);
-
- /* Only handle the non legacy irqs on secondary ioapics */
- if (ioapic_idx == 0 || irq < NR_IRQS_LEGACY)
+ if (mp_init_irq_at_boot(ioapic_idx, irq))
return;

set_io_apic_irq_attr(&attr, ioapic_idx, pin, irq_trigger(idx),
@@ -3524,9 +3539,9 @@ void __init setup_ioapic_dest(void)
irq_entry = find_irq_entry(ioapic, pin, mp_INT);
if (irq_entry == -1)
continue;
- irq = pin_2_irq(irq_entry, ioapic, pin);

- if ((ioapic > 0) && (irq > NR_IRQS_LEGACY))
+ irq = pin_2_irq(irq_entry, ioapic, pin);
+ if (!mp_init_irq_at_boot(ioapic, irq))
continue;

idata = irq_get_irq_data(irq);
--
1.7.10.4

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