From: Chunguang Xu <brookxu@xxxxxxxxxxx> The value range of ioprio is [0, 7], but the result of bfq_weight_to_ioprio() may exceed this range, so simple optimization is required. Signed-off-by: Chunguang Xu <brookxu@xxxxxxxxxxx> --- block/bfq-wf2q.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c index 619ed21..ea5b90d 100644 --- a/block/bfq-wf2q.c +++ b/block/bfq-wf2q.c @@ -527,8 +527,9 @@ unsigned short bfq_ioprio_to_weight(int ioprio) */ static unsigned short bfq_weight_to_ioprio(int weight) { - return max_t(int, 0, - IOPRIO_BE_NR * BFQ_WEIGHT_CONVERSION_COEFF - weight); + int ioprio = IOPRIO_BE_NR - weight / BFQ_WEIGHT_CONVERSION_COEFF; + + return ioprio < 0 ? 0 : min_t(int, ioprio, IOPRIO_BE_NR - 1); } static void bfq_get_entity(struct bfq_entity *entity) -- 1.8.3.1