Re: [PATCH v2 1/3] PM: introduce pm_ptr() macro

From: Paul Cercueil <paul@crapouillou.net>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ulf Hansson <ulf.hansson@linaro.org>, Pavel Machek <pavel@ucw.cz>,
	Len Brown <len.brown@intel.com>,
	od@zcrc.me, linux-mmc@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org
Subject: Re: [PATCH v2 1/3] PM: introduce pm_ptr() macro
Date: Sun, 26 Apr 2020 19:06:40 +0200	[thread overview]
Message-ID: <4JNE9Q.Y5HBZ952XKLI@crapouillou.net> (raw)
In-Reply-To: <2708095.iQXV2FnTNx@kreacher>

Hi Rafael,

Le dim. 26 avril 2020 à 17:40, Rafael J. Wysocki <rjw@rjwysocki.net> a 
écrit :
> On Monday, April 13, 2020 2:32:05 PM CEST Paul Cercueil wrote:
>>  This macro is analogous to the infamous of_match_ptr(). If CONFIG_PM
>>  is enabled, this macro will resolve to its argument, otherwise to 
>> NULL.
> 
> Well, this is going to result in quite a bit of unused code being
> added to the kernels built with CONFIG_PM unset.
> 
> Is there any way to avoid that somehow?

Using __maybe_unused on the dev_pm_ops struct and the callbacks, as 
long as they are static, they should be dropped by the compiler when 
CONFIG_PM is not set.

-Paul

> 
>>  Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>>  ---
>> 
>>  Notes:
>>      v2: Remove pm_sleep_ptr() macro
>> 
>>   include/linux/pm.h | 6 ++++++
>>   1 file changed, 6 insertions(+)
>> 
>>  diff --git a/include/linux/pm.h b/include/linux/pm.h
>>  index e057d1fa2469..1c0eec06905d 100644
>>  --- a/include/linux/pm.h
>>  +++ b/include/linux/pm.h
>>  @@ -374,6 +374,12 @@ const struct dev_pm_ops name = { \
>>   	SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
>>   }
>> 
>>  +#ifdef CONFIG_PM
>>  +#define pm_ptr(_ptr) (_ptr)
>>  +#else
>>  +#define pm_ptr(_ptr) NULL
>>  +#endif
>>  +
>>   /*
>>    * PM_EVENT_ messages
>>    *
>> 
> 
> 
> 
> 