Commit 0f70a49f authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

genirq: Provide conditional lock guards 



The interrupt core code has an ever repeating pattern:

    unsigned long flags;
    struct irq_desc *desc = irq_get_desc_[bus]lock(irq, &flags, mode);

    if (!desc)
       return -EINVAL;
    ....
    irq_put_desc_[bus]unlock(desc, flags);

That requires gotos in failure paths and just creates visual clutter.

Provide lock guards, which allow to simplify the code.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/20250429065420.061659985@linutronix.de
parent e5032ead

kernel/irq/internals.h

+29 −6
Original line number Diff line number Diff line
@@ -141,6 +141,10 @@ extern int irq_setup_affinity(struct irq_desc *desc); 
static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }

#endif





#define for_each_action_of_desc(desc, act)			\

	for (act = desc->action; act; act = act->next)



/* Inline functions for support of irq chips on slow busses */

static inline void chip_bus_lock(struct irq_desc *desc)

{
@@ -160,14 +164,33 @@ static inline void chip_bus_sync_unlock(struct irq_desc *desc) 
#define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)

#define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)



#define for_each_action_of_desc(desc, act)			\

	for (act = desc->action; act; act = act->next)



struct irq_desc *

__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,

struct irq_desc *__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,

				     unsigned int check);

void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);



__DEFINE_CLASS_IS_CONDITIONAL(irqdesc_lock, true);

__DEFINE_UNLOCK_GUARD(irqdesc_lock, struct irq_desc,

		      __irq_put_desc_unlock(_T->lock, _T->flags, _T->bus),

		      unsigned long flags; bool bus);



static inline class_irqdesc_lock_t class_irqdesc_lock_constructor(unsigned int irq, bool bus,

								  unsigned int check)

{

	class_irqdesc_lock_t _t = {

		.bus	= bus,

		.lock	= __irq_get_desc_lock(irq, &_t.flags, bus, check),

	};

	return _t;

}



#define scoped_irqdesc_get_and_lock(_irq, _check)		\

	scoped_guard(irqdesc_lock, _irq, false, _check)



#define scoped_irqdesc_get_and_buslock(_irq, _check)		\

	scoped_guard(irqdesc_lock, _irq, true, _check)



#define scoped_irqdesc		((struct irq_desc *)(__guard_ptr(irqdesc_lock)(&scope)))



static inline struct irq_desc *

irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)

{