[PATCH v2 09/64] dmaengine: ioat: convert cleanup tasklet to dma_chan BH

[Allen Pais]

Replace the per-channel tasklet with the shared dma_chan BH helper.
The handler continues to run in softirq context while dmaengine owns
the common scheduling and teardown mechanism.

Signed-off-by: Allen Pais <allen.lkml@xxxxxxxxx>
---
 drivers/dma/ioat/dma.c  | 14 +++++++-------
 drivers/dma/ioat/dma.h  |  3 +--
 drivers/dma/ioat/init.c |  2 +-
 3 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index ee93b029f9e3..827b46c6354a 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -110,7 +110,7 @@ irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
 	for_each_set_bit(bit, &attnstatus, BITS_PER_LONG) {
 		ioat_chan = ioat_chan_by_index(instance, bit);
 		if (test_bit(IOAT_RUN, &ioat_chan->state))
-			tasklet_schedule(&ioat_chan->cleanup_task);
+			dma_chan_schedule_bh(&ioat_chan->dma_chan);
 	}
 
 	writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
@@ -127,7 +127,7 @@ irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
 	struct ioatdma_chan *ioat_chan = data;
 
 	if (test_bit(IOAT_RUN, &ioat_chan->state))
-		tasklet_schedule(&ioat_chan->cleanup_task);
+		dma_chan_schedule_bh(&ioat_chan->dma_chan);
 
 	return IRQ_HANDLED;
 }
@@ -161,11 +161,11 @@ void ioat_stop(struct ioatdma_chan *ioat_chan)
 	/* flush inflight timers */
 	timer_delete_sync(&ioat_chan->timer);
 
-	/* flush inflight tasklet runs */
-	tasklet_kill(&ioat_chan->cleanup_task);
+	/* flush inflight BH runs */
+	dma_chan_kill_bh(&ioat_chan->dma_chan);
 
 	/* final cleanup now that everything is quiesced and can't re-arm */
-	ioat_cleanup_event(&ioat_chan->cleanup_task);
+	ioat_cleanup_event(&ioat_chan->dma_chan);
 }
 
 static void __ioat_issue_pending(struct ioatdma_chan *ioat_chan)
@@ -690,9 +690,9 @@ static void ioat_cleanup(struct ioatdma_chan *ioat_chan)
 	spin_unlock_bh(&ioat_chan->cleanup_lock);
 }
 
-void ioat_cleanup_event(struct tasklet_struct *t)
+void ioat_cleanup_event(struct dma_chan *c)
 {
-	struct ioatdma_chan *ioat_chan = from_tasklet(ioat_chan, t, cleanup_task);
+	struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
 
 	ioat_cleanup(ioat_chan);
 	if (!test_bit(IOAT_RUN, &ioat_chan->state))
diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index e8a880f338c6..4bdb1ae937e4 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -111,7 +111,6 @@ struct ioatdma_chan {
 	struct ioatdma_device *ioat_dma;
 	dma_addr_t completion_dma;
 	u64 *completion;
-	struct tasklet_struct cleanup_task;
 	struct kobject kobj;
 
 /* ioat v2 / v3 channel attributes
@@ -385,7 +384,7 @@ int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
 enum dma_status
 ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
 		struct dma_tx_state *txstate);
-void ioat_cleanup_event(struct tasklet_struct *t);
+void ioat_cleanup_event(struct dma_chan *c);
 void ioat_timer_event(struct timer_list *t);
 int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
 void ioat_issue_pending(struct dma_chan *chan);
diff --git a/drivers/dma/ioat/init.c b/drivers/dma/ioat/init.c
index 737496391109..314676e1cbc4 100644
--- a/drivers/dma/ioat/init.c
+++ b/drivers/dma/ioat/init.c
@@ -765,7 +765,7 @@ ioat_init_channel(struct ioatdma_device *ioat_dma,
 	list_add_tail(&ioat_chan->dma_chan.device_node, &dma->channels);
 	ioat_dma->idx[idx] = ioat_chan;
 	timer_setup(&ioat_chan->timer, ioat_timer_event, 0);
-	tasklet_setup(&ioat_chan->cleanup_task, ioat_cleanup_event);
+	dma_chan_init_bh(&ioat_chan->dma_chan, ioat_cleanup_event);
 }
 
 #define IOAT_NUM_SRC_TEST 6 /* must be <= 8 */
-- 
2.43.0