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Revision 1604f31895dcdb42edf6511ce7ef0546ff92c8e5 authored by Matthew Wilcox on 04 October 2006, 21:12:52 UTC, committed by Matthew Wilcox on 05 October 2006, 01:48:18 UTC 
[PA-RISC] Fix time.c for new do_timer() calling convention
 
do_timer now wants to know how many ticks have elapsed.  Now that we
have to calculate that, we can eliminate some of the clever code that
avoided having to calculate that.  Also add some more documentation.
I'd like to thank Grant Grundler for helping me with this.

Signed-off-by: Matthew Wilcox <willy@parisc-linux.org>
1 parent 1070c96
Raw File
int_sqrt.c 

#include <linux/kernel.h>
#include <linux/module.h>

/**
 * int_sqrt - rough approximation to sqrt
 * @x: integer of which to calculate the sqrt
 *
 * A very rough approximation to the sqrt() function.
 */
unsigned long int_sqrt(unsigned long x)
{
	unsigned long op, res, one;

	op = x;
	res = 0;

	one = 1UL << (BITS_PER_LONG - 2);
	while (one > op)
		one >>= 2;

	while (one != 0) {
		if (op >= res + one) {
			op = op - (res + one);
			res = res +  2 * one;
		}
		res /= 2;
		one /= 4;
	}
	return res;
}
EXPORT_SYMBOL(int_sqrt);
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