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-rw-r--r--fs/gfs2/lock_dlm.c37
1 files changed, 20 insertions, 17 deletions
diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c
index 153272f82984..dac040162ecc 100644
--- a/fs/gfs2/lock_dlm.c
+++ b/fs/gfs2/lock_dlm.c
@@ -24,28 +24,31 @@
/**
* gfs2_update_stats - Update time based stats
- * @mv: Pointer to mean/variance structure to update
+ * @s: The stats to update (local or global)
+ * @index: The index inside @s
* @sample: New data to include
- *
- * @delta is the difference between the current rtt sample and the
- * running average srtt. We add 1/8 of that to the srtt in order to
- * update the current srtt estimate. The variance estimate is a bit
- * more complicated. We subtract the current variance estimate from
- * the abs value of the @delta and add 1/4 of that to the running
- * total. That's equivalent to 3/4 of the current variance
- * estimate plus 1/4 of the abs of @delta.
- *
- * Note that the index points at the array entry containing the smoothed
- * mean value, and the variance is always in the following entry
- *
- * Reference: TCP/IP Illustrated, vol 2, p. 831,832
- * All times are in units of integer nanoseconds. Unlike the TCP/IP case,
- * they are not scaled fixed point.
*/
-
static inline void gfs2_update_stats(struct gfs2_lkstats *s, unsigned index,
s64 sample)
{
+ /*
+ * @delta is the difference between the current rtt sample and the
+ * running average srtt. We add 1/8 of that to the srtt in order to
+ * update the current srtt estimate. The variance estimate is a bit
+ * more complicated. We subtract the current variance estimate from
+ * the abs value of the @delta and add 1/4 of that to the running
+ * total. That's equivalent to 3/4 of the current variance
+ * estimate plus 1/4 of the abs of @delta.
+ *
+ * Note that the index points at the array entry containing the
+ * smoothed mean value, and the variance is always in the following
+ * entry
+ *
+ * Reference: TCP/IP Illustrated, vol 2, p. 831,832
+ * All times are in units of integer nanoseconds. Unlike the TCP/IP
+ * case, they are not scaled fixed point.
+ */
+
s64 delta = sample - s->stats[index];
s->stats[index] += (delta >> 3);
index++;