alistair23-linux/arch/x86/kernel/irq_work.c
Frederic Weisbecker 3010279f0f x86: Tell irq work about self IPI support
x86 supports irq work self-IPIs when local apic is available. This is
partly known on runtime so lets implement arch_irq_work_has_interrupt()
accordingly.

This should be safely called after setup_arch().

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-09-13 18:38:29 +02:00

51 lines
986 B
C

/*
* x86 specific code for irq_work
*
* Copyright (C) 2010 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
*/
#include <linux/kernel.h>
#include <linux/irq_work.h>
#include <linux/hardirq.h>
#include <asm/apic.h>
#include <asm/trace/irq_vectors.h>
static inline void irq_work_entering_irq(void)
{
irq_enter();
ack_APIC_irq();
}
static inline void __smp_irq_work_interrupt(void)
{
inc_irq_stat(apic_irq_work_irqs);
irq_work_run();
}
__visible void smp_irq_work_interrupt(struct pt_regs *regs)
{
irq_work_entering_irq();
__smp_irq_work_interrupt();
exiting_irq();
}
__visible void smp_trace_irq_work_interrupt(struct pt_regs *regs)
{
irq_work_entering_irq();
trace_irq_work_entry(IRQ_WORK_VECTOR);
__smp_irq_work_interrupt();
trace_irq_work_exit(IRQ_WORK_VECTOR);
exiting_irq();
}
void arch_irq_work_raise(void)
{
#ifdef CONFIG_X86_LOCAL_APIC
if (!arch_irq_work_has_interrupt())
return;
apic->send_IPI_self(IRQ_WORK_VECTOR);
apic_wait_icr_idle();
#endif
}