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| #include <linux/kernel.h>
| #include <asm/div64.h>
| #include <linux/reciprocal_div.h>
| #include <linux/export.h>
|
| /*
| * For a description of the algorithm please have a look at
| * include/linux/reciprocal_div.h
| */
|
| struct reciprocal_value reciprocal_value(u32 d)
| {
| struct reciprocal_value R;
| u64 m;
| int l;
|
| l = fls(d - 1);
| m = ((1ULL << 32) * ((1ULL << l) - d));
| do_div(m, d);
| ++m;
| R.m = (u32)m;
| R.sh1 = min(l, 1);
| R.sh2 = max(l - 1, 0);
|
| return R;
| }
| EXPORT_SYMBOL(reciprocal_value);
|
|
