[tip:x86/apic] x86, intr-remap: fix ack for interrupt remapping

From: tip-bot for Weidong Han
Date: Fri Apr 17 2009 - 10:50:30 EST


Commit-ID: 631dd7572e66ee524bb7dfe7dbc883f3484c7eee
Gitweb: http://git.kernel.org/tip/631dd7572e66ee524bb7dfe7dbc883f3484c7eee
Author: Weidong Han <weidong.han@xxxxxxxxx>
AuthorDate: Fri, 17 Apr 2009 16:42:13 +0800
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Fri, 17 Apr 2009 16:23:44 +0200

x86, intr-remap: fix ack for interrupt remapping

Shouldn't call ack_apic_edge() in ir_ack_apic_edge(), because
ack_apic_edge() does more than just ack: it also does irq migration
in the non-interrupt-remapping case. But there is no such need for
interrupt-remapping case, as irq migration is done in the process
context.

Similarly, ir_ack_apic_level() shouldn't call ack_apic_level, and
instead should do the local cpu's EOI + directed EOI to the io-apic.

ack_x2APIC_irq() is not neccessary, because ack_APIC_irq() will use MSR
write for x2apic, and uncached write for non-x2apic.

[ Impact: simplify/standardize intr-remap IRQ acking, fix on !x2apic ]

Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
Signed-off-by: Weidong Han <weidong.han@xxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: dwmw2@xxxxxxxxxxxxx
Cc: allen.m.kay@xxxxxxxxx
Cc: fenghua.yu@xxxxxxxxx
LKML-Reference: <1239957736-6161-3-git-send-email-weidong.han@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
arch/x86/include/asm/apic.h | 8 --------
arch/x86/kernel/apic/io_apic.c | 32 +++++---------------------------
2 files changed, 5 insertions(+), 35 deletions(-)

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 2bd5a46..d4cb7e5 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -204,14 +204,6 @@ static inline int x2apic_enabled(void)

extern int get_physical_broadcast(void);

-#ifdef CONFIG_X86_X2APIC
-static inline void ack_x2APIC_irq(void)
-{
- /* Docs say use 0 for future compatibility */
- native_apic_msr_write(APIC_EOI, 0);
-}
-#endif
-
extern void apic_disable(void);
extern int lapic_get_maxlvt(void);
extern void clear_local_APIC(void);
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 8499000..ea22a86 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2552,20 +2552,6 @@ eoi_ioapic_irq(struct irq_desc *desc)
spin_unlock_irqrestore(&ioapic_lock, flags);
}

-#ifdef CONFIG_X86_X2APIC
-static void ack_x2apic_level(unsigned int irq)
-{
- struct irq_desc *desc = irq_to_desc(irq);
- ack_x2APIC_irq();
- eoi_ioapic_irq(desc);
-}
-
-static void ack_x2apic_edge(unsigned int irq)
-{
- ack_x2APIC_irq();
-}
-#endif
-
static void ack_apic_edge(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
@@ -2629,9 +2615,6 @@ static void ack_apic_level(unsigned int irq)
*/
ack_APIC_irq();

- if (irq_remapped(irq))
- eoi_ioapic_irq(desc);
-
/* Now we can move and renable the irq */
if (unlikely(do_unmask_irq)) {
/* Only migrate the irq if the ack has been received.
@@ -2680,20 +2663,15 @@ static void ack_apic_level(unsigned int irq)
#ifdef CONFIG_INTR_REMAP
static void ir_ack_apic_edge(unsigned int irq)
{
-#ifdef CONFIG_X86_X2APIC
- if (x2apic_enabled())
- return ack_x2apic_edge(irq);
-#endif
- return ack_apic_edge(irq);
+ ack_APIC_irq();
}

static void ir_ack_apic_level(unsigned int irq)
{
-#ifdef CONFIG_X86_X2APIC
- if (x2apic_enabled())
- return ack_x2apic_level(irq);
-#endif
- return ack_apic_level(irq);
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ ack_APIC_irq();
+ eoi_ioapic_irq(desc);
}
#endif /* CONFIG_INTR_REMAP */

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