Loop was repalaced with __builtin_clz(). This still allows to precompute
constants, but on some architectures it uses special instruction to
calculate order.
Signed-off-by: Maksym Planeta <mcsim.planeta@xxxxxxxxx>
---
include/asm-generic/getorder.h | 8 +++-----
1 files changed, 3 insertions(+), 5 deletions(-)
diff --git a/include/asm-generic/getorder.h b/include/asm-generic/getorder.h
index 67e7245..fe8020c 100644
--- a/include/asm-generic/getorder.h
+++ b/include/asm-generic/getorder.h
@@ -11,11 +11,9 @@ 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);
+ order = (__builtin_clzl(size) ^ (BITS_PER_LONG - 1));
+ if (size == 0)
+ order = 0;
return order;
}
--
1.7.2.3
--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
