linux/include/asm-x86_64/hw_irq.h
Eric W. Biederman 70a0a5357d [PATCH] x86-64: Only look at per_cpu data for online cpus.
When I generalized __assign_irq_vector I failed to pay attention
to what happens when you access a per cpu data structure for
a cpu that is not online.   It is an undefined case making any
code that does it have undefined behavior as well.

The code still needs to be able to allocate a vector across cpus
that are not online to properly handle combinations like lowest
priority interrupt delivery and cpu_hotplug.  Not that we can do
that today but the infrastructure shouldn't prevent it.

So this patch updates the places where we touch per cpu data
to only touch online cpus, it makes cpu vector allocation
an atomic operation with respect to cpu hotplug, and it updates
the cpu start code to properly initialize vector_irq so we
don't have inconsistencies.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andi Kleen <ak@suse.de>
2006-10-25 01:00:23 +02:00

134 lines
3.4 KiB
C

#ifndef _ASM_HW_IRQ_H
#define _ASM_HW_IRQ_H
/*
* linux/include/asm/hw_irq.h
*
* (C) 1992, 1993 Linus Torvalds, (C) 1997 Ingo Molnar
*
* moved some of the old arch/i386/kernel/irq.h to here. VY
*
* IRQ/IPI changes taken from work by Thomas Radke
* <tomsoft@informatik.tu-chemnitz.de>
*
* hacked by Andi Kleen for x86-64.
*/
#ifndef __ASSEMBLY__
#include <asm/atomic.h>
#include <asm/irq.h>
#include <linux/profile.h>
#include <linux/smp.h>
#include <linux/percpu.h>
#endif
#define NMI_VECTOR 0x02
/*
* IDT vectors usable for external interrupt sources start
* at 0x20:
*/
#define FIRST_EXTERNAL_VECTOR 0x20
#define IA32_SYSCALL_VECTOR 0x80
/*
* Vectors 0x20-0x2f are used for ISA interrupts.
*/
/*
* Special IRQ vectors used by the SMP architecture, 0xf0-0xff
*
* some of the following vectors are 'rare', they are merged
* into a single vector (CALL_FUNCTION_VECTOR) to save vector space.
* TLB, reschedule and local APIC vectors are performance-critical.
*/
#define SPURIOUS_APIC_VECTOR 0xff
#define ERROR_APIC_VECTOR 0xfe
#define RESCHEDULE_VECTOR 0xfd
#define CALL_FUNCTION_VECTOR 0xfc
/* fb free - please don't readd KDB here because it's useless
(hint - think what a NMI bit does to a vector) */
#define THERMAL_APIC_VECTOR 0xfa
#define THRESHOLD_APIC_VECTOR 0xf9
/* f8 free */
#define INVALIDATE_TLB_VECTOR_END 0xf7
#define INVALIDATE_TLB_VECTOR_START 0xf0 /* f0-f7 used for TLB flush */
#define NUM_INVALIDATE_TLB_VECTORS 8
/*
* Local APIC timer IRQ vector is on a different priority level,
* to work around the 'lost local interrupt if more than 2 IRQ
* sources per level' errata.
*/
#define LOCAL_TIMER_VECTOR 0xef
/*
* First APIC vector available to drivers: (vectors 0x30-0xee)
* we start at 0x31 to spread out vectors evenly between priority
* levels. (0x80 is the syscall vector)
*/
#define FIRST_DEVICE_VECTOR 0x31
#define FIRST_SYSTEM_VECTOR 0xef /* duplicated in irq.h */
#ifndef __ASSEMBLY__
typedef int vector_irq_t[NR_VECTORS];
DECLARE_PER_CPU(vector_irq_t, vector_irq);
extern void __setup_vector_irq(int cpu);
extern spinlock_t vector_lock;
/*
* Various low-level irq details needed by irq.c, process.c,
* time.c, io_apic.c and smp.c
*
* Interrupt entry/exit code at both C and assembly level
*/
extern void disable_8259A_irq(unsigned int irq);
extern void enable_8259A_irq(unsigned int irq);
extern int i8259A_irq_pending(unsigned int irq);
extern void make_8259A_irq(unsigned int irq);
extern void init_8259A(int aeoi);
extern void FASTCALL(send_IPI_self(int vector));
extern void init_VISWS_APIC_irqs(void);
extern void setup_IO_APIC(void);
extern void disable_IO_APIC(void);
extern void print_IO_APIC(void);
extern int IO_APIC_get_PCI_irq_vector(int bus, int slot, int fn);
extern void send_IPI(int dest, int vector);
extern void setup_ioapic_dest(void);
extern unsigned long io_apic_irqs;
extern atomic_t irq_err_count;
extern atomic_t irq_mis_count;
#define IO_APIC_IRQ(x) (((x) >= 16) || ((1<<(x)) & io_apic_irqs))
#define __STR(x) #x
#define STR(x) __STR(x)
#include <asm/ptrace.h>
#define IRQ_NAME2(nr) nr##_interrupt(void)
#define IRQ_NAME(nr) IRQ_NAME2(IRQ##nr)
/*
* SMP has a few special interrupts for IPI messages
*/
#define BUILD_IRQ(nr) \
asmlinkage void IRQ_NAME(nr); \
__asm__( \
"\n.p2align\n" \
"IRQ" #nr "_interrupt:\n\t" \
"push $~(" #nr ") ; " \
"jmp common_interrupt");
#define platform_legacy_irq(irq) ((irq) < 16)
#endif
#endif /* _ASM_HW_IRQ_H */