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Commit 0c50f6f3 authored by Matt Fleming's avatar Matt Fleming Committed by Paul Mundt
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sh: Make the atomic functions safe for irqsoff tracing 



The irqsoff tracer uses the atomic_* functions internally, but the
implementations of those functions in arch/sh/include/asm/atomic-irq.h
disable irqs to achieve atomicity. A continuous loop ensues where we
disable interrupts, trace the interrupt disabling, call atomic_*
functions, disable interrupts, trace the interrupt disabling, etc..

The simplest solution to all this is to just convert uses of
local_irq_save()/local_irq_restore() the raw_* equivalents because the
raw_* equivalents don't call trace_hardirqs_on()/trace_hardirqs_off().

Signed-off-by: default avatarMatt Fleming <matt@console-pimps.org>
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 3767f3f1

arch/sh/include/asm/atomic-irq.h

+12 −12
Original line number Diff line number Diff line
@@ -10,29 +10,29 @@ static inline void atomic_add(int i, atomic_t *v) 
{

	unsigned long flags;



	local_irq_save(flags);

	raw_local_irq_save(flags);

	v->counter += i;

	local_irq_restore(flags);

	raw_local_irq_restore(flags);

}



static inline void atomic_sub(int i, atomic_t *v)

{

	unsigned long flags;



	local_irq_save(flags);

	raw_local_irq_save(flags);

	v->counter -= i;

	local_irq_restore(flags);

	raw_local_irq_restore(flags);

}



static inline int atomic_add_return(int i, atomic_t *v)

{

	unsigned long temp, flags;



	local_irq_save(flags);

	raw_local_irq_save(flags);

	temp = v->counter;

	temp += i;

	v->counter = temp;

	local_irq_restore(flags);

	raw_local_irq_restore(flags);



	return temp;

}
@@ -41,11 +41,11 @@ static inline int atomic_sub_return(int i, atomic_t *v) 
{

	unsigned long temp, flags;



	local_irq_save(flags);

	raw_local_irq_save(flags);

	temp = v->counter;

	temp -= i;

	v->counter = temp;

	local_irq_restore(flags);

	raw_local_irq_restore(flags);



	return temp;

}
@@ -54,18 +54,18 @@ static inline void atomic_clear_mask(unsigned int mask, atomic_t *v) 
{

	unsigned long flags;



	local_irq_save(flags);

	raw_local_irq_save(flags);

	v->counter &= ~mask;

	local_irq_restore(flags);

	raw_local_irq_restore(flags);

}



static inline void atomic_set_mask(unsigned int mask, atomic_t *v)

{

	unsigned long flags;



	local_irq_save(flags);

	raw_local_irq_save(flags);

	v->counter |= mask;

	local_irq_restore(flags);

	raw_local_irq_restore(flags);

}



#endif /* __ASM_SH_ATOMIC_IRQ_H */