This is a note to let you know that I've just added the patch titled
block/bfq_wf2q: correct weight to ioprio
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
block-bfq_wf2q-correct-weight-to-ioprio.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7f30d2516ee7dcca22e332045a426be4aada33d1
Author: Yahu Gao <gaoyahu19@xxxxxxxxx>
Date: Fri Jan 7 14:58:59 2022 +0800
block/bfq_wf2q: correct weight to ioprio
[ Upstream commit bcd2be763252f3a4d5fc4d6008d4d96c601ee74b ]
The return value is ioprio * BFQ_WEIGHT_CONVERSION_COEFF or 0.
What we want is ioprio or 0.
Correct this by changing the calculation.
Signed-off-by: Yahu Gao <gaoyahu19@xxxxxxxxx>
Acked-by: Paolo Valente <paolo.valente@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220107065859.25689-1-gaoyahu19@xxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c
index b74cc0da118e..709b901de3ca 100644
--- a/block/bfq-wf2q.c
+++ b/block/bfq-wf2q.c
@@ -519,7 +519,7 @@ unsigned short bfq_ioprio_to_weight(int ioprio)
static unsigned short bfq_weight_to_ioprio(int weight)
{
return max_t(int, 0,
- IOPRIO_NR_LEVELS * BFQ_WEIGHT_CONVERSION_COEFF - weight);
+ IOPRIO_NR_LEVELS - weight / BFQ_WEIGHT_CONVERSION_COEFF);
}
static void bfq_get_entity(struct bfq_entity *entity)
