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Date: Wed, 28 Jun 2017 20:21:16 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Mark Rutland <mark.rutland@arm.com>
cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
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Subject: Re: [PATCH] locking/atomics: don't alias ____ptr
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On Wed, 28 Jun 2017, Mark Rutland wrote:
> On Wed, Jun 28, 2017 at 05:24:24PM +0200, Thomas Gleixner wrote:
> Given we're gonig to clean things up, we may as well avoid the backwards
> include of <asm-generic/atomic_instrumented.h>, whcih was only there as
> a bodge:
> 
> For the UP arches we do:
> # echo '#include <asm-generic/atomic_up.h>' >arch/xxx/include/asm/atomic.h
> # mv include/asm-generic/atomic.h include/asm-generic/atomic_up.h
> 
> Then we add a <linux/atomic_instrumented.h>:
> 
> #ifndef __LINUX_ATOMIC_INSTRUMENTED_H
> #define __LINUX_ATOMIC INSTRUMENTED_H
> 
> #include <asm/atomic.h>
> 
> #if CONFIG_ATOMIC_INSTRUMENTED_H
> <instrumentation>
> #endif
> 
> #endif /* __LINUX_ATOMIC_ARCH_H */
> 
> ... and make <linux/atomic.h> incldue that rather than <asm/atomic.h>.
> 
> That way the instrumentation's orthogonal to the UP-ness of the arch,
> and we can fold any other instrumentation in there, or later move it
> directly into <linux/atomic.h>

Sounds like a plan.

Thanks,

	tglx