From 0b31c10c667b774e6d373c8f1146c93cff21a0cd Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 28 Jun 2016 09:04:02 +0200 Subject: [PATCH] cfq-iosched: Charge at least 1 jiffie instead of 1 ns Commit 9a7f38c42c2b (cfq-iosched: Convert from jiffies to nanoseconds) could result in charging just 1 ns to a cgroup submitting IO instead of 1 jiffie we always charged before. It is arguable what is the right amount to change but for now lets retain the old behavior of always charging at least one jiffie. Fixes: 9a7f38c42c2b92391d9dabaf9f51df7cfe5608e4 Signed-off-by: Jan Kara Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 2d03004dc77c..892afd6d40e2 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1463,7 +1463,8 @@ static inline u64 cfq_cfqq_slice_usage(struct cfq_queue *cfqq, * a single request on seeky media and cause lots of seek time * and group will never know it. */ - slice_used = max_t(u64, (now - cfqq->dispatch_start), 1); + slice_used = max_t(u64, (now - cfqq->dispatch_start), + jiffies_to_nsecs(1)); } else { slice_used = now - cfqq->slice_start; if (slice_used > cfqq->allocated_slice) { -- 2.20.1