[PATCH v2 19/64] dmaengine: xilinx-dma: use dma_chan BH instead of tasklets

From: Allen Pais

Date: Mon Jul 27 2026 - 16:38:26 EST


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/xilinx/xilinx_dma.c | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)

diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index 404235c17353..bf9f22ed1265 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -402,7 +402,6 @@ struct xilinx_dma_tx_descriptor {
* @err: Channel has errors
* @idle: Check for channel idle
* @terminating: Check for channel being synchronized by user
- * @tasklet: Cleanup work after irq
* @config: Device configuration info
* @flush_on_fsync: Flush on Frame sync
* @desc_pendingcount: Descriptor pending count
@@ -441,7 +440,6 @@ struct xilinx_dma_chan {
bool err;
bool idle;
bool terminating;
- struct tasklet_struct tasklet;
struct xilinx_vdma_config config;
bool flush_on_fsync;
u32 desc_pendingcount;
@@ -1115,11 +1113,12 @@ static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)

/**
* xilinx_dma_do_tasklet - Schedule completion tasklet
- * @t: Pointer to the Xilinx DMA channel structure
+ * @c: Pointer to the Xilinx DMA channel structure
*/
-static void xilinx_dma_do_tasklet(struct tasklet_struct *t)
+static void xilinx_dma_do_tasklet(struct dma_chan *c)
{
- struct xilinx_dma_chan *chan = from_tasklet(chan, t, tasklet);
+ struct xilinx_dma_chan *chan = container_of(c,
+ struct xilinx_dma_chan, common);

xilinx_dma_chan_desc_cleanup(chan);
}
@@ -1898,7 +1897,7 @@ static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
spin_unlock(&chan->lock);
}

- tasklet_hi_schedule(&chan->tasklet);
+ dma_chan_schedule_bh(&chan->common);
return IRQ_HANDLED;
}

@@ -1955,7 +1954,7 @@ static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
spin_unlock(&chan->lock);
}

- tasklet_schedule(&chan->tasklet);
+ dma_chan_schedule_bh(&chan->common);
return IRQ_HANDLED;
}

@@ -2654,7 +2653,7 @@ static void xilinx_dma_synchronize(struct dma_chan *dchan)
{
struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);

- tasklet_kill(&chan->tasklet);
+ dma_chan_kill_bh(&chan->common);
}

/**
@@ -2745,7 +2744,7 @@ static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
if (chan->irq > 0)
free_irq(chan->irq, chan);

- tasklet_kill(&chan->tasklet);
+ dma_chan_kill_bh(&chan->common);

list_del(&chan->common.device_node);
}
@@ -3075,8 +3074,7 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
str_enabled_disabled(chan->has_sg));
}

- /* Initialize the tasklet */
- tasklet_setup(&chan->tasklet, xilinx_dma_do_tasklet);
+ dma_chan_init_bh(&chan->common, xilinx_dma_do_tasklet);

/*
* Initialize the DMA channel and add it to the DMA engine channels
--
2.43.0