Re: PREEMPT is messing with everyone

[Bill Davidsen <davidsen@tmr.com>]

Jaswinder Singh wrote:
> On 12/5/06, Michal Schmidt <xschmi00@stud.feec.vutbr.cz> wrote:
>> Jaswinder Singh wrote:
>> > Hi,
>> >
>> > preempt stuff SHOULD only stay in #ifdef CONFIG_PREEMP_* , but it is
>> > messing with everyone even though not defined.
>> >
>> > e.g.
>> >
>> > 1. linux-2.6.19/kernel/spinlock.c
>> >
>> > Line 18: #include <linux/preempt.h>
>> >
>> > Line 26:  preempt_disable();
>> >
>> > Line 32:  preempt_disable();
>> >
>> > and so on .
>>
>> Don't worry. These compile into "do { } while (0)" (i.e. nothing) when
>> CONFIG_PREEMPT is not set.
>>
> 
> Yes, Compiler will remove it but this looks ugly and confusing.
> 
> Why dont we use like this :-

Because it's ugly and confusing.
> 
> #ifdef CONFIG_PREEMPT
> #include <linux/preempt.h>
> #endif
> 
> #ifdef CONFIG_PREEMPT
> preempt_disable();
> #endif
> 
> #ifdef CONFIG_PREEMPT
> preempt_enable();
> #endif


-- 
bill davidsen <davidsen@tmr.com>
   CTO TMR Associates, Inc
   Doing interesting things with small computers since 1979