Merge tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Core block changes that have been queued up for this release:

   - Remove dead blk-throttle and blk-wbt code (Guoqing)

   - Include pid in blktrace note traces (Jan)

   - Don't spew I/O errors on wouldblock termination (me)

   - Zone append addition (Johannes, Keith, Damien)

   - IO accounting improvements (Konstantin, Christoph)

   - blk-mq hardware map update improvements (Ming)

   - Scheduler dispatch improvement (Salman)

   - Inline block encryption support (Satya)

   - Request map fixes and improvements (Weiping)

   - blk-iocost tweaks (Tejun)

   - Fix for timeout failing with error injection (Keith)

   - Queue re-run fixes (Douglas)

   - CPU hotplug improvements (Christoph)

   - Queue entry/exit improvements (Christoph)

   - Move DMA drain handling to the few drivers that use it (Christoph)

   - Partition handling cleanups (Christoph)"

* tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block: (127 commits)
  block: mark bio_wouldblock_error() bio with BIO_QUIET
  blk-wbt: rename __wbt_update_limits to wbt_update_limits
  blk-wbt: remove wbt_update_limits
  blk-throttle: remove tg_drain_bios
  blk-throttle: remove blk_throtl_drain
  null_blk: force complete for timeout request
  blk-mq: drain I/O when all CPUs in a hctx are offline
  blk-mq: add blk_mq_all_tag_iter
  blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx
  blk-mq: use BLK_MQ_NO_TAG in more places
  blk-mq: rename BLK_MQ_TAG_FAIL to BLK_MQ_NO_TAG
  blk-mq: move more request initialization to blk_mq_rq_ctx_init
  blk-mq: simplify the blk_mq_get_request calling convention
  blk-mq: remove the bio argument to ->prepare_request
  nvme: force complete cancelled requests
  blk-mq: blk-mq: provide forced completion method
  block: fix a warning when blkdev.h is included for !CONFIG_BLOCK builds
  block: blk-crypto-fallback: remove redundant initialization of variable err
  block: reduce part_stat_lock() scope
  block: use __this_cpu_add() instead of access by smp_processor_id()
  ...

1 files changed, 6 insertions, 0 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 930212c1a512..0ecc897b225c 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1530,6 +1530,10 @@ static void blkcg_scale_delay(struct blkcg_gq *blkg, u64 now)
 {
 	u64 old = atomic64_read(&blkg->delay_start);
 
+	/* negative use_delay means no scaling, see blkcg_set_delay() */
+	if (atomic_read(&blkg->use_delay) < 0)
+		return;
+
 	/*
 	 * We only want to scale down every second.  The idea here is that we
 	 * want to delay people for min(delay_nsec, NSEC_PER_SEC) in a certain
@@ -1717,6 +1721,8 @@ void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay)
  */
 void blkcg_add_delay(struct blkcg_gq *blkg, u64 now, u64 delta)
 {
+	if (WARN_ON_ONCE(atomic_read(&blkg->use_delay) < 0))
+		return;
 	blkcg_scale_delay(blkg, now);
 	atomic64_add(delta, &blkg->delay_nsec);
 }