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SubjectRe: [PATCH] irqflags: fix (at least latent) code generation issue

* Jan Beulich <JBeulich@suse.com> wrote:

> The conditional in local_irq_restore() otherwise can cause code bloat
> (the if and else blocks may get translated into separate code paths
> despite the generated code being identical, dependent on compiler
> internal heuristics). Note that this adjustment gets the code in sync
> with the comment preceding it (which was slightly wrong from at least
> from 2.6.37 onwards).
>
> The code bloat was observed in reality with an experimental x86 patch
> I'm about to post as RFC.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> ---
> include/linux/irqflags.h | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> --- 3.18-rc3/include/linux/irqflags.h
> +++ 3.18-rc3-irqflags/include/linux/irqflags.h
> @@ -85,7 +85,7 @@
> * The local_irq_*() APIs are equal to the raw_local_irq*()
> * if !TRACE_IRQFLAGS.
> */
> -#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
> +#ifdef CONFIG_TRACE_IRQFLAGS
> #define local_irq_enable() \
> do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0)
> #define local_irq_disable() \
> @@ -131,7 +131,7 @@
> } while (0)
>
>
> -#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
> +#else /* !CONFIG_TRACE_IRQFLAGS */
>
> #define local_irq_enable() do { raw_local_irq_enable(); } while (0)
> #define local_irq_disable() do { raw_local_irq_disable(); } while (0)
> @@ -145,6 +145,6 @@
> #define irqs_disabled_flags(flags) (raw_irqs_disabled_flags(flags))
> #define safe_halt() do { raw_safe_halt(); } while (0)
>
> -#endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
> +#endif /* CONFIG_TRACE_IRQFLAGS */

So this breaks a couple of non-x86 architectures, such as MIPS:

/home/mingo/tip/include/acpi/platform/aclinuxex.h: In function 'acpi_os_allocate':
/home/mingo/tip/include/acpi/platform/aclinuxex.h:86: error: implicit declaration of function 'arch_irqs_disabled'

Thanks,

Ingo


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