aboutsummaryrefslogtreecommitdiff
path: root/kernel/timer.c
diff options
context:
space:
mode:
authorJeff Garzik <[email protected]>2005-10-30 20:37:44 -0500
committerJeff Garzik <[email protected]>2005-10-30 20:37:44 -0500
commit9e0cb06b17be7e562cbdaba2768649f025826dc6 (patch)
treeaaf5ef8c6cd11764d222df9c446ad9af17e0020e /kernel/timer.c
parent23da0c20ef1c1f0432f373e0e2233a6b6ab2678f (diff)
parent6e9d6b8ee4e0c37d3952256e6472c57490d6780d (diff)
Merge branch 'master'
Diffstat (limited to 'kernel/timer.c')
-rw-r--r--kernel/timer.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/timer.c b/kernel/timer.c
index 3ba10fa35b60..6a2e5f8dc725 100644
--- 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)