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[PATCH]: highest_possible_processor_id() has to be a macro
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	... 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>
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Al Viro authored and David S. Miller committed Oct 16, 2005
1 parent e6850cc commit 688ce17
Showing 1 changed file with 7 additions and 9 deletions.
16 changes: 7 additions & 9 deletions include/linux/cpumask.h
Original file line number Diff line number Diff line change
Expand Up @@ -393,15 +393,13 @@ extern cpumask_t cpu_present_map;
#define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)

/* Find the highest possible smp_processor_id() */
static inline unsigned int highest_possible_processor_id(void)
{
unsigned int cpu, highest = 0;

for_each_cpu_mask(cpu, cpu_possible_map)
highest = cpu;

return highest;
}
#define highest_possible_processor_id() \
({ \
unsigned int cpu, highest = 0; \
for_each_cpu_mask(cpu, cpu_possible_map) \
highest = cpu; \
highest; \
})


#endif /* __LINUX_CPUMASK_H */

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