Tasklets have long been deprecated as being too heavy on the system
by running in irq context - and this is not a performance critical
path. If a higher priority process wants to run, it must wait for
the tasklet to finish before doing so.
Use a more suitable alternative such as threaded irqs and do the
async work in process context.
Signed-off-by: Davidlohr Bueso <dbu...@suse.de>
---
drivers/mailbox/bcm-pdc-mailbox.c | 23 +++++++----------------
1 file changed, 7 insertions(+), 16 deletions(-)
diff --git a/drivers/mailbox/bcm-pdc-mailbox.c
b/drivers/mailbox/bcm-pdc-mailbox.c
index 5b375985f7b8..4718722c3c67 100644
--- a/drivers/mailbox/bcm-pdc-mailbox.c
+++ b/drivers/mailbox/bcm-pdc-mailbox.c
@@ -294,9 +294,6 @@ struct pdc_state {
unsigned int pdc_irq;
- /* tasklet for deferred processing after DMA rx interrupt */
- struct tasklet_struct rx_tasklet;
-
/* Number of bytes of receive status prior to each rx frame */
u32 rx_status_len;
/* Whether a BCM header is prepended to each frame */
@@ -953,23 +950,23 @@ static irqreturn_t pdc_irq_handler(int irq, void *data)
iowrite32(intstatus, pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET);
/* Wakeup IRQ thread */
- tasklet_schedule(&pdcs->rx_tasklet);
- return IRQ_HANDLED;
+ return IRQ_WAKE_THREAD;
}
/**
- * pdc_tasklet_cb() - Tasklet callback that runs the deferred processing after
+ * pdc_task_cb() - Threaded IRQ that runs the deferred processing after
* a DMA receive interrupt. Reenables the receive interrupt.
* @data: PDC state structure
*/
-static void pdc_tasklet_cb(struct tasklet_struct *t)
+static irqreturn_t pdc_task_cb(int irq, void *data)
{
- struct pdc_state *pdcs = from_tasklet(pdcs, t, rx_tasklet);
+ struct pdc_state *pdcs = data;
pdc_receive(pdcs);
/* reenable interrupts */
iowrite32(PDC_INTMASK, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET);
+ return IRQ_HANDLED;
}
/**
@@ -1405,8 +1402,8 @@ static int pdc_interrupts_init(struct pdc_state *pdcs)
dev_dbg(dev, "pdc device %s irq %u for pdcs %p",
dev_name(dev), pdcs->pdc_irq, pdcs);
- err = devm_request_irq(dev, pdcs->pdc_irq, pdc_irq_handler, 0,
- dev_name(dev), dev);
+ err = devm_request_threaded_irq(dev, pdcs->pdc_irq, pdc_irq_handler,
+ pdc_task_cb, 0, dev_name(dev), dev);
if (err) {
dev_err(dev, "IRQ %u request failed with err %d\n",
pdcs->pdc_irq, err);
@@ -1588,9 +1585,6 @@ static int pdc_probe(struct platform_device *pdev)
pdc_hw_init(pdcs);
- /* Init tasklet for deferred DMA rx processing */
- tasklet_setup(&pdcs->rx_tasklet, pdc_tasklet_cb);
-
err = pdc_interrupts_init(pdcs);
if (err)
goto cleanup_buf_pool;
@@ -1606,7 +1600,6 @@ static int pdc_probe(struct platform_device *pdev)
return PDC_SUCCESS;
cleanup_buf_pool:
- tasklet_kill(&pdcs->rx_tasklet);
dma_pool_destroy(pdcs->rx_buf_pool);
cleanup_ring_pool:
@@ -1622,8 +1615,6 @@ static int pdc_remove(struct platform_device *pdev)
pdc_free_debugfs();
- tasklet_kill(&pdcs->rx_tasklet);
-
pdc_hw_disable(pdcs);
dma_pool_destroy(pdcs->rx_buf_pool);
--
2.26.2
