Commit 43a25632 authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
Browse files

sparseirq: move __weak symbols into separate compilation unit 



GCC has a bug with __weak alias functions: if the functions are in
the same compilation unit as their call site, GCC can decide to
inline them - and thus rob the linker of the opportunity to override
the weak alias with the real thing.

So move all the IRQ handling related __weak symbols to kernel/irq/chip.c.

Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b2e2fe99

include/linux/interrupt.h

+6 −0
Original line number Diff line number Diff line
@@ -467,4 +467,10 @@ static inline void init_irq_proc(void) 


int show_interrupts(struct seq_file *p, void *v);



struct irq_desc;



extern int early_irq_init(void);

extern int arch_early_irq_init(void);

extern int arch_init_chip_data(struct irq_desc *desc, int cpu);



#endif

include/linux/irq.h

+0 −3
Original line number Diff line number Diff line
@@ -193,9 +193,6 @@ struct irq_desc { 
	const char		*name;

} ____cacheline_internodealigned_in_smp;



extern int early_irq_init(void);

extern int arch_early_irq_init(void);

extern int arch_init_chip_data(struct irq_desc *desc, int cpu);

extern void arch_init_copy_chip_data(struct irq_desc *old_desc,

					struct irq_desc *desc, int cpu);

extern void arch_free_chip_data(struct irq_desc *old_desc, struct irq_desc *desc);

init/main.c

+0 −10
Original line number Diff line number Diff line
@@ -539,16 +539,6 @@ void __init __weak thread_info_cache_init(void) 
{

}



int __init __weak arch_early_irq_init(void)

{

	return 0;

}



int __init __weak early_irq_init(void)

{

	return arch_early_irq_init();

}



asmlinkage void __init start_kernel(void)

{

	char * command_line;

kernel/irq/manage.c

+0 −9
Original line number Diff line number Diff line
@@ -261,15 +261,6 @@ void enable_irq(unsigned int irq) 
}

EXPORT_SYMBOL(enable_irq);



/*

 * [ Not in kernel/irq/handle.c, so that GCC does not

 *   inline the __weak alias: ]

 */

int __weak arch_init_chip_data(struct irq_desc *desc, int cpu)

{

	return 0;

}



static int set_irq_wake_real(unsigned int irq, unsigned int on)

{

	struct irq_desc *desc = irq_to_desc(irq);

kernel/softirq.c

+20 −0
Original line number Diff line number Diff line
@@ -797,3 +797,23 @@ int on_each_cpu(void (*func) (void *info), void *info, int wait) 
}

EXPORT_SYMBOL(on_each_cpu);

#endif



/*

 * [ These __weak aliases are kept in a separate compilation unit, so that

 *   GCC does not inline them incorrectly. ]

 */



int __init __weak early_irq_init(void)

{

	return 0;

}



int __init __weak arch_early_irq_init(void)

{

	return 0;

}



int __weak arch_init_chip_data(struct irq_desc *desc, int cpu)

{

	return 0;

}

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