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Server : Apache/2.4.18 (Ubuntu) System : Linux canvaswebdesign 3.13.0-71-generic #114-Ubuntu SMP Tue Dec 1 02:34:22 UTC 2015 x86_64 User : oppastar ( 1041) PHP Version : 7.0.33-0ubuntu0.16.04.15 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority, Directory : /usr/src/linux-headers-4.4.0-184/include/asm-generic/ |
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#ifndef __ASM_GENERIC_GETORDER_H
#define __ASM_GENERIC_GETORDER_H
#ifndef __ASSEMBLY__
#include <linux/compiler.h>
#include <linux/log2.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.
*/
static inline __attribute_const__ int get_order(unsigned long size)
{
if (__builtin_constant_p(size)) {
if (!size)
return BITS_PER_LONG - PAGE_SHIFT;
if (size < (1UL << PAGE_SHIFT))
return 0;
return ilog2((size) - 1) - PAGE_SHIFT + 1;
}
size--;
size >>= PAGE_SHIFT;
#if BITS_PER_LONG == 32
return fls(size);
#else
return fls64(size);
#endif
}
#endif /* __ASSEMBLY__ */
#endif /* __ASM_GENERIC_GETORDER_H */