[PATCH] hrtimer: move div_long_long_rem out of jiffies.h
Thomas Gleixner [Tue, 10 Jan 2006 04:52:20 +0000 (20:52 -0800)]
move div_long_long_rem() from jiffies.h into a new calc64.h include file, as
it is a general math function useful for other things than the jiffy code.
Convert it to an inline function

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/calc64.h [new file with mode: 0644]
include/linux/jiffies.h

diff --git a/include/linux/calc64.h b/include/linux/calc64.h
new file mode 100644 (file)
index 0000000..ebf4b8f
--- /dev/null
@@ -0,0 +1,49 @@
+#ifndef _LINUX_CALC64_H
+#define _LINUX_CALC64_H
+
+#include <linux/types.h>
+#include <asm/div64.h>
+
+/*
+ * This is a generic macro which is used when the architecture
+ * specific div64.h does not provide a optimized one.
+ *
+ * The 64bit dividend is divided by the divisor (data type long), the
+ * result is returned and the remainder stored in the variable
+ * referenced by remainder (data type long *). In contrast to the
+ * do_div macro the dividend is kept intact.
+ */
+#ifndef div_long_long_rem
+#define div_long_long_rem(dividend, divisor, remainder)        \
+       do_div_llr((dividend), divisor, remainder)
+
+static inline unsigned long do_div_llr(const long long dividend,
+                                      const long divisor, long *remainder)
+{
+       u64 result = dividend;
+
+       *(remainder) = do_div(result, divisor);
+       return (unsigned long) result;
+}
+#endif
+
+/*
+ * Sign aware variation of the above. On some architectures a
+ * negative dividend leads to an divide overflow exception, which
+ * is avoided by the sign check.
+ */
+static inline long div_long_long_rem_signed(const long long dividend,
+                                           const long divisor, long *remainder)
+{
+       long res;
+
+       if (unlikely(dividend < 0)) {
+               res = -div_long_long_rem(-dividend, divisor, remainder);
+               *remainder = -(*remainder);
+       } else
+               res = div_long_long_rem(dividend, divisor, remainder);
+
+       return res;
+}
+
+#endif
index 6acfdbb..99905e1 100644 (file)
@@ -1,21 +1,12 @@
 #ifndef _LINUX_JIFFIES_H
 #define _LINUX_JIFFIES_H
 
+#include <linux/calc64.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/time.h>
 #include <linux/timex.h>
 #include <asm/param.h>                 /* for HZ */
-#include <asm/div64.h>
-
-#ifndef div_long_long_rem
-#define div_long_long_rem(dividend,divisor,remainder) \
-({                                                     \
-       u64 result = dividend;                          \
-       *remainder = do_div(result,divisor);            \
-       result;                                         \
-})
-#endif
 
 /*
  * The following defines establish the engineering parameters of the PLL
@@ -373,8 +364,11 @@ jiffies_to_timeval(const unsigned long jiffies, struct timeval *value)
         * one divide.
         */
        u64 nsec = (u64)jiffies * TICK_NSEC;
-       value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &value->tv_usec);
-       value->tv_usec /= NSEC_PER_USEC;
+       long tv_usec;
+
+       value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tv_usec);
+       tv_usec /= NSEC_PER_USEC;
+       value->tv_usec = tv_usec;
 }
 
 /*