add an inlined version of iter_div_u64_rem

iter_div_u64_rem is used in the x86-64 vdso, which cannot call other kernel code. For this case, provide the always_inlined version, __iter_div_u64_rem. Signed-off-by: Jeremy Fitzhardinge <[email protected]> Signed-off-by: Ingo Molnar <[email protected]>
chewitt · Jun 12, 2008 · d5e181f · d5e181f
1 parent f595ec9
commit d5e181f
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diff --git a/include/linux/math64.h b/include/linux/math64.h
@@ -83,4 +83,23 @@ 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;
+}
+
 #endif /* _LINUX_MATH64_H */
diff --git a/lib/div64.c b/lib/div64.c
@@ -105,19 +105,6 @@ EXPORT_SYMBOL(div64_u64);
  */
 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;
+	return __iter_div_u64_rem(dividend, divisor, remainder);
 }
 EXPORT_SYMBOL(iter_div_u64_rem);