From bcd2be763252f3a4d5fc4d6008d4d96c601ee74b Mon Sep 17 00:00:00 2001
From: Yahu Gao <gaoyahu19@gmail.com>
Date: Fri, 7 Jan 2022 14:58:59 +0800
Subject: [PATCH] block/bfq_wf2q: correct weight to ioprio
Git-commit: bcd2be763252f3a4d5fc4d6008d4d96c601ee74b
Patch-mainline: v5.18-rc1
References: git-fixes
 
The return value is ioprio * BFQ_WEIGHT_CONVERSION_COEFF or 0.
What we want is ioprio or 0.
Correct this by changing the calculation.
 
(Coly Li: rebased for Linux v5.14 based SUSE kernel)
 
Signed-off-by: Yahu Gao <gaoyahu19@gmail.com>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220107065859.25689-1-gaoyahu19@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Coly Li <colyli@suse.de>
 
---
 block/bfq-wf2q.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
 
--- a/block/bfq-wf2q.c
+++ b/block/bfq-wf2q.c
@@ -519,7 +519,7 @@ unsigned short bfq_ioprio_to_weight(int
 static unsigned short bfq_weight_to_ioprio(int weight)
 {
 	return max_t(int, 0,
-		     IOPRIO_BE_NR * BFQ_WEIGHT_CONVERSION_COEFF - weight);
+		     IOPRIO_BE_NR - weight / BFQ_WEIGHT_CONVERSION_COEFF);
 }
 
 static void bfq_get_entity(struct bfq_entity *entity)