kernel_optimize_test/include/linux/irqdesc.h
Eric Dumazet 6c9ae009b2 irq: use per_cpu kstat_irqs
Use modern per_cpu API to increment {soft|hard}irq counters, and use
per_cpu allocation for (struct irq_desc)->kstats_irq instead of an array.

This gives better SMP/NUMA locality and saves few instructions per irq.

With small nr_cpuids values (8 for example), kstats_irq was a small array
(less than L1_CACHE_BYTES), potentially source of false sharing.

In the !CONFIG_SPARSE_IRQ case, remove the huge, NUMA/cache unfriendly
kstat_irqs_all[NR_IRQS][NR_CPUS] array.

Note: we still populate kstats_irq for all possible irqs in
early_irq_init().  We probably could use on-demand allocations.  (Code
included in alloc_descs()).  Problem is not all IRQS are used with a prior
alloc_descs() call.

kstat_irqs_this_cpu() is not used anymore, remove it.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:31 -08:00

160 lines
4.4 KiB
C

#ifndef _LINUX_IRQDESC_H
#define _LINUX_IRQDESC_H
/*
* Core internal functions to deal with irq descriptors
*
* This include will move to kernel/irq once we cleaned up the tree.
* For now it's included from <linux/irq.h>
*/
struct proc_dir_entry;
struct timer_rand_state;
/**
* struct irq_desc - interrupt descriptor
* @irq_data: per irq and chip data passed down to chip functions
* @timer_rand_state: pointer to timer rand state struct
* @kstat_irqs: irq stats per cpu
* @handle_irq: highlevel irq-events handler [if NULL, __do_IRQ()]
* @action: the irq action chain
* @status: status information
* @depth: disable-depth, for nested irq_disable() calls
* @wake_depth: enable depth, for multiple set_irq_wake() callers
* @irq_count: stats field to detect stalled irqs
* @last_unhandled: aging timer for unhandled count
* @irqs_unhandled: stats field for spurious unhandled interrupts
* @lock: locking for SMP
* @pending_mask: pending rebalanced interrupts
* @threads_active: number of irqaction threads currently running
* @wait_for_threads: wait queue for sync_irq to wait for threaded handlers
* @dir: /proc/irq/ procfs entry
* @name: flow handler name for /proc/interrupts output
*/
struct irq_desc {
#ifdef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED
struct irq_data irq_data;
#else
/*
* This union will go away, once we fixed the direct access to
* irq_desc all over the place. The direct fields are a 1:1
* overlay of irq_data.
*/
union {
struct irq_data irq_data;
struct {
unsigned int irq;
unsigned int node;
struct irq_chip *chip;
void *handler_data;
void *chip_data;
struct msi_desc *msi_desc;
#ifdef CONFIG_SMP
cpumask_var_t affinity;
#endif
};
};
#endif
struct timer_rand_state *timer_rand_state;
unsigned int __percpu *kstat_irqs;
irq_flow_handler_t handle_irq;
struct irqaction *action; /* IRQ action list */
unsigned int status; /* IRQ status */
unsigned int depth; /* nested irq disables */
unsigned int wake_depth; /* nested wake enables */
unsigned int irq_count; /* For detecting broken IRQs */
unsigned long last_unhandled; /* Aging timer for unhandled count */
unsigned int irqs_unhandled;
raw_spinlock_t lock;
#ifdef CONFIG_SMP
const struct cpumask *affinity_hint;
#ifdef CONFIG_GENERIC_PENDING_IRQ
cpumask_var_t pending_mask;
#endif
#endif
atomic_t threads_active;
wait_queue_head_t wait_for_threads;
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *dir;
#endif
const char *name;
} ____cacheline_internodealigned_in_smp;
#ifndef CONFIG_SPARSE_IRQ
extern struct irq_desc irq_desc[NR_IRQS];
#endif
/* Will be removed once the last users in power and sh are gone */
extern struct irq_desc *irq_to_desc_alloc_node(unsigned int irq, int node);
static inline struct irq_desc *move_irq_desc(struct irq_desc *desc, int node)
{
return desc;
}
#ifdef CONFIG_GENERIC_HARDIRQS
#define get_irq_desc_chip(desc) ((desc)->irq_data.chip)
#define get_irq_desc_chip_data(desc) ((desc)->irq_data.chip_data)
#define get_irq_desc_data(desc) ((desc)->irq_data.handler_data)
#define get_irq_desc_msi(desc) ((desc)->irq_data.msi_desc)
/*
* Monolithic do_IRQ implementation.
*/
#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
extern unsigned int __do_IRQ(unsigned int irq);
#endif
/*
* Architectures call this to let the generic IRQ layer
* handle an interrupt. If the descriptor is attached to an
* irqchip-style controller then we call the ->handle_irq() handler,
* and it calls __do_IRQ() if it's attached to an irqtype-style controller.
*/
static inline void generic_handle_irq_desc(unsigned int irq, struct irq_desc *desc)
{
#ifdef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
desc->handle_irq(irq, desc);
#else
if (likely(desc->handle_irq))
desc->handle_irq(irq, desc);
else
__do_IRQ(irq);
#endif
}
static inline void generic_handle_irq(unsigned int irq)
{
generic_handle_irq_desc(irq, irq_to_desc(irq));
}
/* Test to see if a driver has successfully requested an irq */
static inline int irq_has_action(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
return desc->action != NULL;
}
static inline int irq_balancing_disabled(unsigned int irq)
{
struct irq_desc *desc;
desc = irq_to_desc(irq);
return desc->status & IRQ_NO_BALANCING_MASK;
}
/* caller has locked the irq_desc and both params are valid */
static inline void __set_irq_handler_unlocked(int irq,
irq_flow_handler_t handler)
{
struct irq_desc *desc;
desc = irq_to_desc(irq);
desc->handle_irq = handler;
}
#endif
#endif