linux/arch/x86/include/asm/hardirq.h
Peter Zijlstra e360adbe29 irq_work: Add generic hardirq context callbacks
Provide a mechanism that allows running code in IRQ context. It is
most useful for NMI code that needs to interact with the rest of the
system -- like wakeup a task to drain buffers.

Perf currently has such a mechanism, so extract that and provide it as
a generic feature, independent of perf so that others may also
benefit.

The IRQ context callback is generated through self-IPIs where
possible, or on architectures like powerpc the decrementer (the
built-in timer facility) is set to generate an interrupt immediately.

Architectures that don't have anything like this get to do with a
callback from the timer tick. These architectures can call
irq_work_run() at the tail of any IRQ handlers that might enqueue such
work (like the perf IRQ handler) to avoid undue latencies in
processing the work.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[ various fixes ]
Signed-off-by: Huang Ying <ying.huang@intel.com>
LKML-Reference: <1287036094.7768.291.camel@yhuang-dev>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-18 19:58:50 +02:00

56 lines
1.5 KiB
C

#ifndef _ASM_X86_HARDIRQ_H
#define _ASM_X86_HARDIRQ_H
#include <linux/threads.h>
#include <linux/irq.h>
typedef struct {
unsigned int __softirq_pending;
unsigned int __nmi_count; /* arch dependent */
unsigned int irq0_irqs;
#ifdef CONFIG_X86_LOCAL_APIC
unsigned int apic_timer_irqs; /* arch dependent */
unsigned int irq_spurious_count;
#endif
unsigned int x86_platform_ipis; /* arch dependent */
unsigned int apic_perf_irqs;
unsigned int apic_irq_work_irqs;
#ifdef CONFIG_SMP
unsigned int irq_resched_count;
unsigned int irq_call_count;
unsigned int irq_tlb_count;
#endif
#ifdef CONFIG_X86_THERMAL_VECTOR
unsigned int irq_thermal_count;
#endif
#ifdef CONFIG_X86_MCE_THRESHOLD
unsigned int irq_threshold_count;
#endif
} ____cacheline_aligned irq_cpustat_t;
DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
/* We can have at most NR_VECTORS irqs routed to a cpu at a time */
#define MAX_HARDIRQS_PER_CPU NR_VECTORS
#define __ARCH_IRQ_STAT
#define inc_irq_stat(member) percpu_inc(irq_stat.member)
#define local_softirq_pending() percpu_read(irq_stat.__softirq_pending)
#define __ARCH_SET_SOFTIRQ_PENDING
#define set_softirq_pending(x) percpu_write(irq_stat.__softirq_pending, (x))
#define or_softirq_pending(x) percpu_or(irq_stat.__softirq_pending, (x))
extern void ack_bad_irq(unsigned int irq);
extern u64 arch_irq_stat_cpu(unsigned int cpu);
#define arch_irq_stat_cpu arch_irq_stat_cpu
extern u64 arch_irq_stat(void);
#define arch_irq_stat arch_irq_stat
#endif /* _ASM_X86_HARDIRQ_H */