kernel-aes67/include/linux/irq.h
Ashok Raj 54d5d42404 [PATCH] x86/x86_64: deferred handling of writes to /proc/irqxx/smp_affinity
When handling writes to /proc/irq, current code is re-programming rte
entries directly. This is not recommended and could potentially cause
chipset's to lockup, or cause missing interrupts.

CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the
interrupt is pending. The same needs to be done for /proc/irq handling as well.
Otherwise user space irq balancers are really not doing the right thing.

- Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for
  lack of a generic name.
- added move_irq out of IRQ_BALANCE, and added this same to X86_64
- Added new proc handler for write, so we can do deferred write at irq
  handling time.
- Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead
  it now shows only active cpu masks, or exactly what was set.
- Provided a common move_irq implementation, instead of duplicating
  when using generic irq framework.

Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off.
Tested UP builds as well.

MSI testing: tbd: I have cards, need to look for a x-over cable, although I
did test an earlier version of this patch.  Will test in a couple days.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Acked-by: Zwane Mwaikambo <zwane@holomorphy.com>
Grudgingly-acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Coywolf Qi Hunt <coywolf@lovecn.org>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:15 -07:00

225 lines
5.7 KiB
C

#ifndef __irq_h
#define __irq_h
/*
* Please do not include this file in generic code. There is currently
* no requirement for any architecture to implement anything held
* within this file.
*
* Thanks. --rmk
*/
#include <linux/config.h>
#if !defined(CONFIG_ARCH_S390)
#include <linux/linkage.h>
#include <linux/cache.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <asm/irq.h>
#include <asm/ptrace.h>
/*
* IRQ line status.
*/
#define IRQ_INPROGRESS 1 /* IRQ handler active - do not enter! */
#define IRQ_DISABLED 2 /* IRQ disabled - do not enter! */
#define IRQ_PENDING 4 /* IRQ pending - replay on enable */
#define IRQ_REPLAY 8 /* IRQ has been replayed but not acked yet */
#define IRQ_AUTODETECT 16 /* IRQ is being autodetected */
#define IRQ_WAITING 32 /* IRQ not yet seen - for autodetection */
#define IRQ_LEVEL 64 /* IRQ level triggered */
#define IRQ_MASKED 128 /* IRQ masked - shouldn't be seen again */
#define IRQ_PER_CPU 256 /* IRQ is per CPU */
/*
* Interrupt controller descriptor. This is all we need
* to describe about the low-level hardware.
*/
struct hw_interrupt_type {
const char * typename;
unsigned int (*startup)(unsigned int irq);
void (*shutdown)(unsigned int irq);
void (*enable)(unsigned int irq);
void (*disable)(unsigned int irq);
void (*ack)(unsigned int irq);
void (*end)(unsigned int irq);
void (*set_affinity)(unsigned int irq, cpumask_t dest);
/* Currently used only by UML, might disappear one day.*/
#ifdef CONFIG_IRQ_RELEASE_METHOD
void (*release)(unsigned int irq, void *dev_id);
#endif
};
typedef struct hw_interrupt_type hw_irq_controller;
/*
* This is the "IRQ descriptor", which contains various information
* about the irq, including what kind of hardware handling it has,
* whether it is disabled etc etc.
*
* Pad this out to 32 bytes for cache and indexing reasons.
*/
typedef struct irq_desc {
hw_irq_controller *handler;
void *handler_data;
struct irqaction *action; /* IRQ action list */
unsigned int status; /* IRQ status */
unsigned int depth; /* nested irq disables */
unsigned int irq_count; /* For detecting broken interrupts */
unsigned int irqs_unhandled;
spinlock_t lock;
#if defined (CONFIG_GENERIC_PENDING_IRQ) || defined (CONFIG_IRQBALANCE)
unsigned int move_irq; /* Flag need to re-target intr dest*/
#endif
} ____cacheline_aligned irq_desc_t;
extern irq_desc_t irq_desc [NR_IRQS];
/* Return a pointer to the irq descriptor for IRQ. */
static inline irq_desc_t *
irq_descp (int irq)
{
return irq_desc + irq;
}
#include <asm/hw_irq.h> /* the arch dependent stuff */
extern int setup_irq(unsigned int irq, struct irqaction * new);
#ifdef CONFIG_GENERIC_HARDIRQS
extern cpumask_t irq_affinity[NR_IRQS];
#ifdef CONFIG_SMP
static inline void set_native_irq_info(int irq, cpumask_t mask)
{
irq_affinity[irq] = mask;
}
#else
static inline void set_native_irq_info(int irq, cpumask_t mask)
{
}
#endif
#ifdef CONFIG_SMP
#if defined (CONFIG_GENERIC_PENDING_IRQ) || defined (CONFIG_IRQBALANCE)
extern cpumask_t pending_irq_cpumask[NR_IRQS];
static inline void set_pending_irq(unsigned int irq, cpumask_t mask)
{
irq_desc_t *desc = irq_desc + irq;
unsigned long flags;
spin_lock_irqsave(&desc->lock, flags);
desc->move_irq = 1;
pending_irq_cpumask[irq] = mask;
spin_unlock_irqrestore(&desc->lock, flags);
}
static inline void
move_native_irq(int irq)
{
cpumask_t tmp;
irq_desc_t *desc = irq_descp(irq);
if (likely (!desc->move_irq))
return;
desc->move_irq = 0;
if (likely(cpus_empty(pending_irq_cpumask[irq])))
return;
if (!desc->handler->set_affinity)
return;
/* note - we hold the desc->lock */
cpus_and(tmp, pending_irq_cpumask[irq], cpu_online_map);
/*
* If there was a valid mask to work with, please
* do the disable, re-program, enable sequence.
* This is *not* particularly important for level triggered
* but in a edge trigger case, we might be setting rte
* when an active trigger is comming in. This could
* cause some ioapics to mal-function.
* Being paranoid i guess!
*/
if (unlikely(!cpus_empty(tmp))) {
desc->handler->disable(irq);
desc->handler->set_affinity(irq,tmp);
desc->handler->enable(irq);
}
cpus_clear(pending_irq_cpumask[irq]);
}
#ifdef CONFIG_PCI_MSI
/*
* Wonder why these are dummies?
* For e.g the set_ioapic_affinity_vector() calls the set_ioapic_affinity_irq()
* counter part after translating the vector to irq info. We need to perform
* this operation on the real irq, when we dont use vector, i.e when
* pci_use_vector() is false.
*/
static inline void move_irq(int irq)
{
}
static inline void set_irq_info(int irq, cpumask_t mask)
{
}
#else // CONFIG_PCI_MSI
static inline void move_irq(int irq)
{
move_native_irq(irq);
}
static inline void set_irq_info(int irq, cpumask_t mask)
{
set_native_irq_info(irq, mask);
}
#endif // CONFIG_PCI_MSI
#else // CONFIG_GENERIC_PENDING_IRQ || CONFIG_IRQBALANCE
#define move_irq(x)
#define move_native_irq(x)
#define set_pending_irq(x,y)
static inline void set_irq_info(int irq, cpumask_t mask)
{
set_native_irq_info(irq, mask);
}
#endif // CONFIG_GENERIC_PENDING_IRQ
#else // CONFIG_SMP
#define move_irq(x)
#define move_native_irq(x)
#endif // CONFIG_SMP
extern int no_irq_affinity;
extern int noirqdebug_setup(char *str);
extern fastcall int handle_IRQ_event(unsigned int irq, struct pt_regs *regs,
struct irqaction *action);
extern fastcall unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs);
extern void note_interrupt(unsigned int irq, irq_desc_t *desc,
int action_ret, struct pt_regs *regs);
extern int can_request_irq(unsigned int irq, unsigned long irqflags);
extern void init_irq_proc(void);
#endif
extern hw_irq_controller no_irq_type; /* needed in every arch ? */
#endif
#endif /* __irq_h */