From 27ac86638e77c7103704b191141fac3b779c264d 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 aa795a966fc0 (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: aa795a966fc0e97073dc23c0ef171a487c11a618 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 2d03004dc77cf..892afd6d40e2d 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) { -- 2.39.5