vtimes may wrap and time_before/after64() should be used to determine
whether a given vtime is before or after another. iocg_is_idle() was
incorrectly using plain "<" comparison do determine whether done_vtime
is before vtime. Here, the only thing we're interested in is whether
done_vtime matches vtime which indicates that there's nothing in
flight. Let's test for inequality instead.
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Fixes: 7caa47151ab2 ("blkcg: implement blk-iocost")
Cc: stable@xxxxxxxxxxxxxxx # v5.4+
---
block/blk-iocost.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 27ca68621137..9a599cc28c29 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -1318,7 +1318,7 @@ static bool iocg_is_idle(struct ioc_gq *iocg)
return false;
/* is something in flight? */
- if (atomic64_read(&iocg->done_vtime) < atomic64_read(&iocg->vtime))
+ if (atomic64_read(&iocg->done_vtime) != atomic64_read(&iocg->vtime))
return false;
return true;
