This is a note to let you know that I've just added the patch titled

block,bfq: Disable writeback throttling

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: block-bfq-disable-writeback-throttling.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Wed Dec 20 18:17:52 CET 2017

From: Luca Miccio lucmiccio@gmail.com Date: Mon, 9 Oct 2017 16:27:21 +0200 Subject: block,bfq: Disable writeback throttling

From: Luca Miccio lucmiccio@gmail.com

[ 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@gmail.com Signed-off-by: Paolo Valente paolo.valente@linaro.org Tested-by: Oleksandr Natalenko oleksandr@natalenko.name Tested-by: Lee Tibbert lee.tibbert@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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) {

Patches currently in stable-queue which might be from lucmiccio@gmail.com are

queue-4.14/block-bfq-disable-writeback-throttling.patch