[PATCH v2 04/20] linux/math64.h: Extract common header for vDSO

Vincenzo Frascino
2020-03-06T13:33:06Z

Split math64.h into linux and common headers to make the latter suitable
for inclusion in the vDSO library.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
---
include/common/math64.h | 24 ++++++++++++++++++++++++
include/linux/math64.h | 20 +-------------------
2 files changed, 25 insertions(+), 19 deletions(-)
create mode 100644 include/common/math64.h

diff --git a/include/common/math64.h b/include/common/math64.h
new file mode 100644
index 000000000000..4e1870e40182
--- /dev/null
+++ b/include/common/math64.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __COMMON_MATH64_H
+#define __COMMON_MATH64_H
+
+static __always_inline u32
+__iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
+{
+ u32 ret = 0;
+
+ while (dividend >= divisor) {
+ /* The following asm() prevents the compiler from
+ optimising this loop into a modulo operation. */
+ asm("" : "+rm"(dividend));
+
+ dividend -= divisor;
+ ret++;
+ }
+
+ *remainder = dividend;
+
+ return ret;
+}
+
+#endif /* __COMMON_MATH64_H */
diff --git a/include/linux/math64.h b/include/linux/math64.h
index 65bef21cdddb..54eb486b5d1a 100644
--- a/include/linux/math64.h
+++ b/include/linux/math64.h
@@ -3,6 +3,7 @@
#define _LINUX_MATH64_H

#include <linux/types.h>
+#include <common/math64.h>
#include <asm/div64.h>

#if BITS_PER_LONG == 64
@@ -142,25 +143,6 @@ static inline s64 div_s64(s64 dividend, s32 divisor)

u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder);

-static __always_inline u32
-__iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
-{
- u32 ret = 0;
-
- while (dividend >= divisor) {
- /* The following asm() prevents the compiler from
- optimising this loop into a modulo operation. */
- asm("" : "+rm"(dividend));
-
- dividend -= divisor;
- ret++;
- }
-
- *remainder = dividend;
-
- return ret;
-}
-
#ifndef mul_u32_u32
/*
* Many a GCC version messes this up and generates a 64x64 mult :-(
--
2.25.1