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SubjectRe: 2.6.24-rc6-mm1
On Sun, Dec 23, 2007 at 12:14:10PM -0800, Andrew Morton wrote:
>
> No, the problem is that include/crypto/scatterwalk.h doesn't include enough
> header files to support its inlining fetish. It needs sched.h.

I'll get it fixed in cryptodev.

> Ingo, it's not good that we have cond_resched() definitions conditionally
> duplicated in kernel.h - that's increasing the risk of bugs like this one.

Actually, why do we even have cond_resched when real preemption
is on? It seems to be a waste of space and time.

Any objections to something like this to remove cond_resched with
CONFIG_PREEMPT on (apart from the potential to uncover more bugs
like this one)?

Cheers,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
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--
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 94bc996..a7283c9 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -105,8 +105,8 @@ struct user;
* supposed to.
*/
#ifdef CONFIG_PREEMPT_VOLUNTARY
-extern int cond_resched(void);
-# define might_resched() cond_resched()
+extern int _cond_resched(void);
+# define might_resched() _cond_resched()
#else
# define might_resched() do { } while (0)
#endif
diff --git a/include/linux/sched.h b/include/linux/sched.h
index ac3d496..ae8e9bd 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1863,7 +1863,18 @@ static inline int need_resched(void)
* cond_resched_lock() will drop the spinlock before scheduling,
* cond_resched_softirq() will enable bhs before scheduling.
*/
-extern int cond_resched(void);
+#ifdef CONFIG_PREEMPT
+static inline int cond_resched(void)
+{
+ return 0;
+}
+#else
+extern int _cond_resched(void);
+static inline int cond_resched(void)
+{
+ return _cond_resched();
+}
+#endif
extern int cond_resched_lock(spinlock_t * lock);
extern int cond_resched_softirq(void);

diff --git a/kernel/sched.c b/kernel/sched.c
index 3df84ea..2dc2bbf 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4683,7 +4683,8 @@ static void __cond_resched(void)
} while (need_resched());
}

-int __sched cond_resched(void)
+#if !defined(CONFIG_PREEMPT) || defined(CONFIG_PREEMPT_VOLUNTARY)
+int __sched _cond_resched(void)
{
if (need_resched() && !(preempt_count() & PREEMPT_ACTIVE) &&
system_state == SYSTEM_RUNNING) {
@@ -4692,7 +4693,8 @@ int __sched cond_resched(void)
}
return 0;
}
-EXPORT_SYMBOL(cond_resched);
+EXPORT_SYMBOL(_cond_resched);
+#endif

/*
* cond_resched_lock() - if a reschedule is pending, drop the given lock,

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