Skip to content

Commit

Permalink
blk-mq: initialize mq kobjects in blk_mq_init_allocated_queue()
Browse files Browse the repository at this point in the history
Both q->mq_kobj and sw queues' kobjects should have been initialized
once, instead of doing that each add_disk context.

Also this patch removes clearing of ctx in blk_mq_init_cpu_queues()
because percpu allocator fills zero to allocated variable.

This patch fixes one issue[1] reported from Omar.

[1] kernel wearning when doing unbind/bind on one scsi-mq device

[   19.347924] kobject (ffff8800791ea0b8): tried to init an initialized object, something is seriously wrong.
[   19.349781] CPU: 1 PID: 84 Comm: kworker/u8:1 Not tainted 4.10.0-rc7-00210-g53f39eeaa263 #34
[   19.350686] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-20161122_114906-anatol 04/01/2014
[   19.350920] Workqueue: events_unbound async_run_entry_fn
[   19.350920] Call Trace:
[   19.350920]  dump_stack+0x63/0x83
[   19.350920]  kobject_init+0x77/0x90
[   19.350920]  blk_mq_register_dev+0x40/0x130
[   19.350920]  blk_register_queue+0xb6/0x190
[   19.350920]  device_add_disk+0x1ec/0x4b0
[   19.350920]  sd_probe_async+0x10d/0x1c0 [sd_mod]
[   19.350920]  async_run_entry_fn+0x48/0x150
[   19.350920]  process_one_work+0x1d0/0x480
[   19.350920]  worker_thread+0x48/0x4e0
[   19.350920]  kthread+0x101/0x140
[   19.350920]  ? process_one_work+0x480/0x480
[   19.350920]  ? kthread_create_on_node+0x60/0x60
[   19.350920]  ret_from_fork+0x2c/0x40

Cc: Omar Sandoval <[email protected]>
Signed-off-by: Ming Lei <[email protected]>
Tested-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
  • Loading branch information
ming1 authored and axboe committed Mar 8, 2017
1 parent ec3b93a commit 737f98c
Show file tree
Hide file tree
Showing 3 changed files with 5 additions and 4 deletions.
4 changes: 1 addition & 3 deletions block/blk-mq-sysfs.c
Original file line number Diff line number Diff line change
Expand Up @@ -277,7 +277,7 @@ void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
}

static void blk_mq_sysfs_init(struct request_queue *q)
void blk_mq_sysfs_init(struct request_queue *q)
{
struct blk_mq_ctx *ctx;
int cpu;
Expand All @@ -297,8 +297,6 @@ int blk_mq_register_dev(struct device *dev, struct request_queue *q)

blk_mq_disable_hotplug();

blk_mq_sysfs_init(q);

ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
if (ret < 0)
goto out;
Expand Down
4 changes: 3 additions & 1 deletion block/blk-mq.c
Original file line number Diff line number Diff line change
Expand Up @@ -2045,7 +2045,6 @@ static void blk_mq_init_cpu_queues(struct request_queue *q,
struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i);
struct blk_mq_hw_ctx *hctx;

memset(__ctx, 0, sizeof(*__ctx));
__ctx->cpu = i;
spin_lock_init(&__ctx->lock);
INIT_LIST_HEAD(&__ctx->rq_list);
Expand Down Expand Up @@ -2352,6 +2351,9 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
if (!q->queue_ctx)
goto err_exit;

/* init q->mq_kobj and sw queues' kobjects */
blk_mq_sysfs_init(q);

q->queue_hw_ctx = kzalloc_node(nr_cpu_ids * sizeof(*(q->queue_hw_ctx)),
GFP_KERNEL, set->numa_node);
if (!q->queue_hw_ctx)
Expand Down
1 change: 1 addition & 0 deletions block/blk-mq.h
Original file line number Diff line number Diff line change
Expand Up @@ -77,6 +77,7 @@ static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
/*
* sysfs helpers
*/
extern void blk_mq_sysfs_init(struct request_queue *q);
extern int blk_mq_sysfs_register(struct request_queue *q);
extern void blk_mq_sysfs_unregister(struct request_queue *q);
extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
Expand Down

0 comments on commit 737f98c

Please sign in to comment.