Commit 31a70bb4 authored by Philip J Kelleher's avatar Philip J Kelleher Committed by Jens Axboe
Browse files

rsxx: Fixes soft-lockup issues during DMAs. 



The workqueue mechanism has been reworked to prevent soft
lockup issues from occuring by adding in mutex sychronization.

Signed-off-by: default avatarPhilip J Kelleher <pjk1939@linux.vnet.ibm.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 0ab4743e

drivers/block/rsxx/dma.c

+27 −8
Original line number Diff line number Diff line
@@ -381,15 +381,13 @@ static void dma_engine_stalled(unsigned long data) 
	}

}



static void rsxx_issue_dmas(struct work_struct *work)

static void rsxx_issue_dmas(struct rsxx_dma_ctrl *ctrl)

{

	struct rsxx_dma_ctrl *ctrl;

	struct rsxx_dma *dma;

	int tag;

	int cmds_pending = 0;

	struct hw_cmd *hw_cmd_buf;



	ctrl = container_of(work, struct rsxx_dma_ctrl, issue_dma_work);

	hw_cmd_buf = ctrl->cmd.buf;



	if (unlikely(ctrl->card->halt) ||
@@ -469,9 +467,8 @@ static void rsxx_issue_dmas(struct work_struct *work) 
	}

}



static void rsxx_dma_done(struct work_struct *work)

static void rsxx_dma_done(struct rsxx_dma_ctrl *ctrl)

{

	struct rsxx_dma_ctrl *ctrl;

	struct rsxx_dma *dma;

	unsigned long flags;

	u16 count;
@@ -479,7 +476,6 @@ static void rsxx_dma_done(struct work_struct *work) 
	u8 tag;

	struct hw_status *hw_st_buf;



	ctrl = container_of(work, struct rsxx_dma_ctrl, dma_done_work);

	hw_st_buf = ctrl->status.buf;



	if (unlikely(ctrl->card->halt) ||
@@ -555,6 +551,28 @@ static void rsxx_dma_done(struct work_struct *work) 
	spin_unlock_bh(&ctrl->queue_lock);

}



static void rsxx_schedule_issue(struct work_struct *work)

{

	struct rsxx_dma_ctrl *ctrl;



	ctrl = container_of(work, struct rsxx_dma_ctrl, issue_dma_work);



	mutex_lock(&ctrl->work_lock);

	rsxx_issue_dmas(ctrl);

	mutex_unlock(&ctrl->work_lock);

}



static void rsxx_schedule_done(struct work_struct *work)

{

	struct rsxx_dma_ctrl *ctrl;



	ctrl = container_of(work, struct rsxx_dma_ctrl, dma_done_work);



	mutex_lock(&ctrl->work_lock);

	rsxx_dma_done(ctrl);

	mutex_unlock(&ctrl->work_lock);

}



static int rsxx_queue_discard(struct rsxx_cardinfo *card,

				  struct list_head *q,

				  unsigned int laddr,
@@ -789,6 +807,7 @@ static int rsxx_dma_ctrl_init(struct pci_dev *dev, 
	spin_lock_init(&ctrl->trackers->lock);



	spin_lock_init(&ctrl->queue_lock);

	mutex_init(&ctrl->work_lock);

	INIT_LIST_HEAD(&ctrl->queue);



	setup_timer(&ctrl->activity_timer, dma_engine_stalled,
@@ -802,8 +821,8 @@ static int rsxx_dma_ctrl_init(struct pci_dev *dev, 
	if (!ctrl->done_wq)

		return -ENOMEM;



	INIT_WORK(&ctrl->issue_dma_work, rsxx_issue_dmas);

	INIT_WORK(&ctrl->dma_done_work, rsxx_dma_done);

	INIT_WORK(&ctrl->issue_dma_work, rsxx_schedule_issue);

	INIT_WORK(&ctrl->dma_done_work, rsxx_schedule_done);



	st = rsxx_hw_buffers_init(dev, ctrl);

	if (st)

drivers/block/rsxx/rsxx_priv.h

+1 −0
Original line number Diff line number Diff line
@@ -115,6 +115,7 @@ struct rsxx_dma_ctrl { 
	struct timer_list		activity_timer;

	struct dma_tracker_list		*trackers;

	struct rsxx_dma_stats		stats;

	struct mutex			work_lock;

};



struct rsxx_cardinfo {