Re: [PATCH RFC] introduce pm_call() macro to get rid of most #ifdefCONFIG_PM

From: Arjan van de Ven
Date: Sun Mar 02 2008 - 19:08:51 EST


On Mon, 3 Mar 2008 02:43:08 +0300
Anton Vorontsov <cbouatmailru@xxxxxxxxx> wrote:

> Currently drivers handle CONFIG_PM this way:
>
> #ifdef CONFIG_PM
> drv_suspend() {}
> drv_resume() {}
> #else
> #define drv_suspend NULL
> #define drv_resume NULL
> #endif
>
> struct driver drv = {
> .suspend = drv_suspend,
> .resume = drv_resume,
> };
>
> With this patch, the code above converts into:
>
> drv_suspend() {}
> drv_resume() {}
>
> struct driver drv = {
> .suspend = pm_call(drv_suspend),
> .resume = pm_call(drv_resume),
> };
>
> GCC will optimize away suspend/resume calls if they're really
> not used.
>


to be honest, at this point I would think it's time to remove CONFIG_PM, or rather,
just make it always be there and just get rid of the ifdefs. We're saving 2 words and a bit of code,
but only a case that not even the embedded guys use.
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