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#ifndef __ASM_GENERIC_GETORDER_H
#define __ASM_GENERIC_GETORDER_H
#ifndef __ASSEMBLY__
#include <linux/compiler.h>
/**
* get_order - Determine the allocation order of a memory size
* @size: The size for which to get the order
*
* Determine the allocation order of a particular sized block of memory. This
* is on a logarithmic scale, where:
*
* 0 -> 2^0 * PAGE_SIZE and below
* 1 -> 2^1 * PAGE_SIZE to 2^0 * PAGE_SIZE + 1
* 2 -> 2^2 * PAGE_SIZE to 2^1 * PAGE_SIZE + 1
* 3 -> 2^3 * PAGE_SIZE to 2^2 * PAGE_SIZE + 1
* 4 -> 2^4 * PAGE_SIZE to 2^3 * PAGE_SIZE + 1
* ...
*
* The order returned is used to find the smallest allocation granule required
* to hold an object of the specified size.
*
* The result is undefined if the size is 0.
*
* This function may be used to initialise variables with compile time
* evaluations of constants.
*/
static inline __attribute_const__ int get_order(unsigned long size)
{
int order;
size = (size - 1) >> (PAGE_SHIFT - 1);
order = -1;
do {
size >>= 1;
order++;
} while (size);
return order;
}
#endif /* __ASSEMBLY__ */
#endif /* __ASM_GENERIC_GETORDER_H */
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