linux-kernel - Re: PREEMPT is messing with everyone

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 05 Dec 2006 14:55:24 -0500
From:	Bill Davidsen <davidsen@....com>
To:	Jaswinder Singh <jaswinderrajput@...il.com>
CC:	linux-kernel@...r.kernel.org
Subject: Re: PREEMPT is messing with everyone

Jaswinder Singh wrote:
> On 12/5/06, Michal Schmidt <xschmi00@...d.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@....com>
   CTO TMR Associates, Inc
   Doing interesting things with small computers since 1979
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/