Re: [Linux-ia64] kernel 2.5.69 doesn't compile for UP

[Matthew Wilcox <willy@debian.org>]

On Wed, May 14, 2003 at 03:31:08PM +0200, Eric Piel wrote:
> Hello,
> There is a compile error if not compiling for SMP:

> +#ifdef CONFIG_SMP
>  	if (!tasklist_lock.write_lock)
> +#endif
>  		read_lock(&tasklist_lock);

Yuck.  The right way to do this is read_trylock(&tasklist_lock);
The observant will have noted:

#define write_trylock(lock)     ({preempt_disable();_raw_write_trylock(lock) ? \
                                1 : ({preempt_enable(); 0;});})

/* Where's read_trylock? */

in include/linux/spinlock.h but that doen't justify _not writing it_
when you need it.

-- 
"It's not Hollywood.  War is real, war is primarily not about defeat or
victory, it is about death.  I've seen thousands and thousands of dead bodies.
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