vserver 1.9.3

[linux-2.6.git] / include / linux / times.h

diff --git a/include/linux/times.h b/include/linux/times.h
index ff00f33..0c5aa07 100644 (file)
--- a/include/linux/times.h
+++ b/include/linux/times.h
@@ -55,6 +55,26 @@ static inline u64 jiffies_64_to_clock_t(u64 x)
 }
 #endif
 
+static inline u64 nsec_to_clock_t(u64 x)
+{
+#if (NSEC_PER_SEC % USER_HZ) == 0
+       do_div(x, (NSEC_PER_SEC / USER_HZ));
+#elif (USER_HZ % 512) == 0
+       x *= USER_HZ/512;
+       do_div(x, (NSEC_PER_SEC / 512));
+#else
+       /*
+         * max relative error 5.7e-8 (1.8s per year) for USER_HZ <= 1024,
+         * overflow after 64.99 years.
+         * exact for HZ=60, 72, 90, 120, 144, 180, 300, 600, 900, ...
+         */
+       x *= 9;
+       do_div(x, (unsigned long)((9ull * NSEC_PER_SEC + (USER_HZ/2))
+                                 / USER_HZ));
+#endif
+       return x;
+}
+
 struct tms {
        clock_t tms_utime;
        clock_t tms_stime;