Commit 688ce17b authored Oct 16, 2005 by Al Viro Committed by David S. Miller Oct 16, 2005

[PATCH]: highest_possible_processor_id() has to be a macro



	... otherwise, things like alpha and sparc64 break and break
badly.  They define cpu_possible_map to something else in smp.h
*AFTER* having included cpumask.h.

	If that puppy is a macro, expansion will happen at the actual
caller, when we'd already seen #define cpu_possible_map ... and we will
get the right thing used.

	As an inline helper it will be tokenized before we get to that
define and that's it; no matter what we define later, it won't affect
anything.  We get modules with dependency on cpu_possible_map instead
of the right symbol (phys_cpu_present_map in case of sparc64), or outright
link errors if they are built-in.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent e6850cce

include/linux/cpumask.h

+7 −9

Original line number	Original line	Diff line number	Diff line
	@@ -393,15 +393,13 @@ extern cpumask_t cpu_present_map;
	#define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)		#define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)

	/* Find the highest possible smp_processor_id() */		/* Find the highest possible smp_processor_id() */
	static inline unsigned int highest_possible_processor_id(void)		#define highest_possible_processor_id() \
	{		({ \
	unsigned int cpu, highest = 0;		unsigned int cpu, highest = 0; \
			for_each_cpu_mask(cpu, cpu_possible_map) \
	for_each_cpu_mask(cpu, cpu_possible_map)		highest = cpu; \
	highest = cpu;		highest; \
			})
	return highest;
	}


	#endif /* __LINUX_CPUMASK_H */		#endif /* __LINUX_CPUMASK_H */