Merge tag 'v4.19-rc6' into for-4.20/block

Merge -rc6 in, for two reasons:

1) Resolve a trivial conflict in the blk-mq-tag.c documentation
2) A few important regression fixes went into upstream directly, so
   they aren't in the 4.20 branch.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

* tag 'v4.19-rc6': (780 commits)
  Linux 4.19-rc6
  MAINTAINERS: fix reference to moved drivers/{misc => auxdisplay}/panel.c
  cpufreq: qcom-kryo: Fix section annotations
  perf/core: Add sanity check to deal with pinned event failure
  xen/blkfront: correct purging of persistent grants
  Revert "xen/blkfront: When purging persistent grants, keep them in the buffer"
  selftests/powerpc: Fix Makefiles for headers_install change
  blk-mq: I/O and timer unplugs are inverted in blktrace
  dax: Fix deadlock in dax_lock_mapping_entry()
  x86/boot: Fix kexec booting failure in the SEV bit detection code
  bcache: add separate workqueue for journal_write to avoid deadlock
  drm/amd/display: Fix Edid emulation for linux
  drm/amd/display: Fix Vega10 lightup on S3 resume
  drm/amdgpu: Fix vce work queue was not cancelled when suspend
  Revert "drm/panel: Add device_link from panel device to DRM device"
  xen/blkfront: When purging persistent grants, keep them in the buffer
  clocksource/drivers/timer-atmel-pit: Properly handle error cases
  block: fix deadline elevator drain for zoned block devices
  ACPI / hotplug / PCI: Don't scan for non-hotplug bridges if slot is not bridge
  drm/syncobj: Don't leak fences when WAIT_FOR_SUBMIT is set
  ...

Signed-off-by: Jens Axboe <axboe@kernel.dk>

8 files changed, 16 insertions, 19 deletions

diff --git a/block/bio.c b/block/bio.c
index e9f92b50724d..17a8b0aa7050 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1685,7 +1685,7 @@ void generic_end_io_acct(struct request_queue *q, int req_op,
 	const int sgrp = op_stat_group(req_op);
 	int cpu = part_stat_lock();
 
-	part_stat_add(cpu, part, ticks[sgrp], duration);
+	part_stat_add(cpu, part, nsecs[sgrp], jiffies_to_nsecs(duration));
 	part_round_stats(q, cpu, part);
 	part_dec_in_flight(q, part, op_is_write(req_op));
 
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 76136bea7a7f..992da5592c6e 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1558,8 +1558,10 @@ int blkcg_policy_register(struct blkcg_policy *pol)
 	for (i = 0; i < BLKCG_MAX_POLS; i++)
 		if (!blkcg_policy[i])
 			break;
-	if (i >= BLKCG_MAX_POLS)
+	if (i >= BLKCG_MAX_POLS) {
+		pr_warn("blkcg_policy_register: BLKCG_MAX_POLS too small\n");
 		goto err_unlock;
+	}
 
 	/* Make sure cpd/pd_alloc_fn and cpd/pd_free_fn in pairs */
 	if ((!pol->cpd_alloc_fn ^ !pol->cpd_free_fn) ||
diff --git a/block/blk-core.c b/block/blk-core.c
index 16dd3a989753..f12d2b65e5a5 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2727,17 +2727,15 @@ void blk_account_io_done(struct request *req, u64 now)
 	 * containing request is enough.
 	 */
 	if (blk_do_io_stat(req) && !(req->rq_flags & RQF_FLUSH_SEQ)) {
-		unsigned long duration;
 		const int sgrp = op_stat_group(req_op(req));
 		struct hd_struct *part;
 		int cpu;
 
-		duration = nsecs_to_jiffies(now - req->start_time_ns);
 		cpu = part_stat_lock();
 		part = req->part;
 
 		part_stat_inc(cpu, part, ios[sgrp]);
-		part_stat_add(cpu, part, ticks[sgrp], duration);
+		part_stat_add(cpu, part, nsecs[sgrp], now - req->start_time_ns);
 		part_round_stats(req->q, cpu, part);
 		part_dec_in_flight(req->q, part, rq_data_dir(req));
 
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 40d1667bceac..cfda95b85d34 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -384,11 +384,8 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
 	 * synchronize_rcu() to ensure this function left the critical section
 	 * below.
 	 */
-	rcu_read_lock();
-	if (percpu_ref_is_zero(&q->q_usage_counter)) {
-		rcu_read_unlock();
+	if (!percpu_ref_tryget(&q->q_usage_counter))
 		return;
-	}
 
 	queue_for_each_hw_ctx(q, hctx, i) {
 		struct blk_mq_tags *tags = hctx->tags;
@@ -404,7 +401,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
 			bt_for_each(hctx, &tags->breserved_tags, fn, priv, true);
 		bt_for_each(hctx, &tags->bitmap_tags, fn, priv, false);
 	}
-	rcu_read_unlock();
+	blk_queue_exit(q);
 }
 
 static int bt_alloc(struct sbitmap_queue *bt, unsigned int depth,
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 1e72d53e8f2d..1dc157c85a83 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1631,7 +1631,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 		BUG_ON(!rq->q);
 		if (rq->mq_ctx != this_ctx) {
 			if (this_ctx) {
-				trace_block_unplug(this_q, depth, from_schedule);
+				trace_block_unplug(this_q, depth, !from_schedule);
 				blk_mq_sched_insert_requests(this_q, this_ctx,
 								&ctx_list,
 								from_schedule);
@@ -1651,7 +1651,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 	 * on 'ctx_list'. Do those.
 	 */
 	if (this_ctx) {
-		trace_block_unplug(this_q, depth, from_schedule);
+		trace_block_unplug(this_q, depth, !from_schedule);
 		blk_mq_sched_insert_requests(this_q, this_ctx, &ctx_list,
 						from_schedule);
 	}
diff --git a/block/elevator.c b/block/elevator.c
index e18ac68626e3..8fdcd64ae12e 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -589,7 +589,7 @@ void elv_drain_elevator(struct request_queue *q)
 
 	while (e->type->ops.sq.elevator_dispatch_fn(q, 1))
 		;
-	if (q->nr_sorted && printed++ < 10) {
+	if (q->nr_sorted && !blk_queue_is_zoned(q) && printed++ < 10 ) {
 		printk(KERN_ERR "%s: forced dispatching is broken "
 		       "(nr_sorted=%u), please report this\n",
 		       q->elevator->type->elevator_name, q->nr_sorted);
diff --git a/block/genhd.c b/block/genhd.c
index ef0936184d69..cff6bdf27226 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1352,18 +1352,18 @@ static int diskstats_show(struct seq_file *seqf, void *v)
 			   part_stat_read(hd, ios[STAT_READ]),
 			   part_stat_read(hd, merges[STAT_READ]),
 			   part_stat_read(hd, sectors[STAT_READ]),
-			   jiffies_to_msecs(part_stat_read(hd, ticks[STAT_READ])),
+			   (unsigned int)part_stat_read_msecs(hd, STAT_READ),
 			   part_stat_read(hd, ios[STAT_WRITE]),
 			   part_stat_read(hd, merges[STAT_WRITE]),
 			   part_stat_read(hd, sectors[STAT_WRITE]),
-			   jiffies_to_msecs(part_stat_read(hd, ticks[STAT_WRITE])),
+			   (unsigned int)part_stat_read_msecs(hd, STAT_WRITE),
 			   inflight[0],
 			   jiffies_to_msecs(part_stat_read(hd, io_ticks)),
 			   jiffies_to_msecs(part_stat_read(hd, time_in_queue)),
 			   part_stat_read(hd, ios[STAT_DISCARD]),
 			   part_stat_read(hd, merges[STAT_DISCARD]),
 			   part_stat_read(hd, sectors[STAT_DISCARD]),
-			   jiffies_to_msecs(part_stat_read(hd, ticks[STAT_DISCARD]))
+			   (unsigned int)part_stat_read_msecs(hd, STAT_DISCARD)
 			);
 	}
 	disk_part_iter_exit(&piter);
diff --git a/block/partition-generic.c b/block/partition-generic.c
index 5a8975a1201c..d3d14e81fb12 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -136,18 +136,18 @@ ssize_t part_stat_show(struct device *dev,
 		part_stat_read(p, ios[STAT_READ]),
 		part_stat_read(p, merges[STAT_READ]),
 		(unsigned long long)part_stat_read(p, sectors[STAT_READ]),
-		jiffies_to_msecs(part_stat_read(p, ticks[STAT_READ])),
+		(unsigned int)part_stat_read_msecs(p, STAT_READ),
 		part_stat_read(p, ios[STAT_WRITE]),
 		part_stat_read(p, merges[STAT_WRITE]),
 		(unsigned long long)part_stat_read(p, sectors[STAT_WRITE]),
-		jiffies_to_msecs(part_stat_read(p, ticks[STAT_WRITE])),
+		(unsigned int)part_stat_read_msecs(p, STAT_WRITE),
 		inflight[0],
 		jiffies_to_msecs(part_stat_read(p, io_ticks)),
 		jiffies_to_msecs(part_stat_read(p, time_in_queue)),
 		part_stat_read(p, ios[STAT_DISCARD]),
 		part_stat_read(p, merges[STAT_DISCARD]),
 		(unsigned long long)part_stat_read(p, sectors[STAT_DISCARD]),
-		jiffies_to_msecs(part_stat_read(p, ticks[STAT_DISCARD])));
+		(unsigned int)part_stat_read_msecs(p, STAT_DISCARD));
 }
 
 ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,