Hello.
Add missing compensation for (HZ == 250) != (1 << SHIFT_HZ) in
second_overflow().
Signed-off-by: YOSHIFUJI Hideaki <[email protected]>
diff --git a/kernel/timer.c b/kernel/timer.c
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -752,6 +752,15 @@ static void second_overflow(void)
else
time_adj += (time_adj >> 2) + (time_adj >> 5);
#endif
+#if HZ == 250
+ /* Compensate for (HZ==250) != (1 << SHIFT_HZ).
+ * Add 1.5625% and 0.78125% to get 255.85938; => only 0.05% error (p. 14)
+ */
+ if (time_adj < 0)
+ time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
+ else
+ time_adj += (time_adj >> 6) + (time_adj >> 7);
+#endif
#if HZ == 1000
/* Compensate for (HZ==1000) != (1 << SHIFT_HZ).
* Add 1.5625% and 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
--
YOSHIFUJI Hideaki @ USAGI Project <[email protected]>
GPG-FP : 9022 65EB 1ECF 3AD1 0BDF 80D8 4807 F894 E062 0EEA