[PATCH 4/8] x86: add support for remotely triggering the block softirq

[Jens Axboe <jens.axboe@oracle.com>]

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 arch/x86/kernel/smp_32.c                   |   15 +++++++++++++++
 arch/x86/kernel/smpboot_32.c               |    3 +++
 include/asm-x86/hw_irq_32.h                |    1 +
 include/asm-x86/mach-default/entry_arch.h  |    1 +
 include/asm-x86/mach-default/irq_vectors.h |    1 +
 5 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/smp_32.c b/arch/x86/kernel/smp_32.c
index dc0cde9..668b8a4 100644
--- a/arch/x86/kernel/smp_32.c
+++ b/arch/x86/kernel/smp_32.c
@@ -672,6 +672,21 @@ void smp_call_function_interrupt(struct pt_regs *regs)
 	}
 }
 
+fastcall void smp_raise_block_softirq(struct pt_regs *regs)
+{
+	unsigned long flags;
+
+	ack_APIC_irq();
+	local_irq_save(flags);
+	raise_softirq_irqoff(BLOCK_SOFTIRQ);
+	local_irq_restore(flags);
+}
+
+void arch_raise_softirq_on_cpu(int cpu, unsigned int nr)
+{
+	send_IPI_mask(cpumask_of_cpu(cpu), BLOCK_SOFTIRQ_VECTOR);
+}
+
 static int convert_apicid_to_cpu(int apic_id)
 {
 	int i;
diff --git a/arch/x86/kernel/smpboot_32.c b/arch/x86/kernel/smpboot_32.c
index 579b9b7..ca35697 100644
--- a/arch/x86/kernel/smpboot_32.c
+++ b/arch/x86/kernel/smpboot_32.c
@@ -1304,6 +1304,9 @@ void __init smp_intr_init(void)
 
 	/* IPI for generic function call */
 	set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
+
+	/* IPI for scheduling block softirq */
+	set_intr_gate(BLOCK_SOFTIRQ_VECTOR, raise_block_softirq);
 }
 
 /*
diff --git a/include/asm-x86/hw_irq_32.h b/include/asm-x86/hw_irq_32.h
index ea88054..0a053d8 100644
--- a/include/asm-x86/hw_irq_32.h
+++ b/include/asm-x86/hw_irq_32.h
@@ -32,6 +32,7 @@ extern void (*const interrupt[NR_IRQS])(void);
 void reschedule_interrupt(void);
 void invalidate_interrupt(void);
 void call_function_interrupt(void);
+void raise_block_softirq(void);
 #endif
 
 #ifdef CONFIG_X86_LOCAL_APIC
diff --git a/include/asm-x86/mach-default/entry_arch.h b/include/asm-x86/mach-default/entry_arch.h
index bc86146..e96ed61 100644
--- a/include/asm-x86/mach-default/entry_arch.h
+++ b/include/asm-x86/mach-default/entry_arch.h
@@ -13,6 +13,7 @@
 BUILD_INTERRUPT(reschedule_interrupt,RESCHEDULE_VECTOR)
 BUILD_INTERRUPT(invalidate_interrupt,INVALIDATE_TLB_VECTOR)
 BUILD_INTERRUPT(call_function_interrupt,CALL_FUNCTION_VECTOR)
+BUILD_INTERRUPT(raise_block_softirq,BLOCK_SOFTIRQ_VECTOR);
 #endif
 
 /*
diff --git a/include/asm-x86/mach-default/irq_vectors.h b/include/asm-x86/mach-default/irq_vectors.h
index 881c63c..f7535a3 100644
--- a/include/asm-x86/mach-default/irq_vectors.h
+++ b/include/asm-x86/mach-default/irq_vectors.h
@@ -48,6 +48,7 @@
 #define INVALIDATE_TLB_VECTOR	0xfd
 #define RESCHEDULE_VECTOR	0xfc
 #define CALL_FUNCTION_VECTOR	0xfb
+#define BLOCK_SOFTIRQ_VECTOR	0xfa
 
 #define THERMAL_APIC_VECTOR	0xf0
 /*
-- 
1.5.4.22.g7a20