4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Luca Miccio <lucmiccio@xxxxxxxxx> [ Upstream commit b5dc5d4d1f4ff9032eb6c21a3c571a1317dc9289 ] Similarly to CFQ, BFQ has its write-throttling heuristics, and it is better not to combine them with further write-throttling heuristics of a different nature. So this commit disables write-back throttling for a device if BFQ is used as I/O scheduler for that device. Signed-off-by: Luca Miccio <lucmiccio@xxxxxxxxx> Signed-off-by: Paolo Valente <paolo.valente@xxxxxxxxxx> Tested-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx> Tested-by: Lee Tibbert <lee.tibbert@xxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- block/bfq-iosched.c | 3 ++- block/blk-wbt.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -108,6 +108,7 @@ #include "blk-mq-tag.h" #include "blk-mq-sched.h" #include "bfq-iosched.h" +#include "blk-wbt.h" #define BFQ_BFQQ_FNS(name) \ void bfq_mark_bfqq_##name(struct bfq_queue *bfqq) \ @@ -4775,7 +4776,7 @@ static int bfq_init_queue(struct request bfq_init_root_group(bfqd->root_group, bfqd); bfq_init_entity(&bfqd->oom_bfqq.entity, bfqd->root_group); - + wbt_disable_default(q); return 0; out_free: --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -654,7 +654,7 @@ void wbt_set_write_cache(struct rq_wb *r } /* - * Disable wbt, if enabled by default. Only called from CFQ. + * Disable wbt, if enabled by default. */ void wbt_disable_default(struct request_queue *q) {