diff options
| -rw-r--r-- | block/cfq-iosched.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 5c3cee93329a..4ab33d8a20b2 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -507,8 +507,14 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq, } else rb_key += jiffies; } else if (!add_front) { + /* + * Get our rb key offset. Subtract any residual slice + * value carried from last service. A negative resid + * count indicates slice overrun, and this should position + * the next service time further away in the tree. + */ rb_key = cfq_slice_offset(cfqd, cfqq) + jiffies; - rb_key += cfqq->slice_resid; + rb_key -= cfqq->slice_resid; cfqq->slice_resid = 0; } else { rb_key = -HZ; |