[v2,1/2] dmaengine: tegra-apb: Don't save/restore IRQ flags in interrupt handler

Commit Message

Dmitry Osipenko March 19, 2020, 9:23 p.m. UTC

The interrupt is already disabled while interrupt handler is running, and
thus, there is no need to save/restore the IRQ flags within the spinlock.

Signed-off-by: Dmitry Osipenko <[e-mail]>
---

Changelog:

v2: No change.

 drivers/dma/tegra20-apb-dma.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

Comments

Vinod Koul March 23, 2020, 6:36 a.m. UTC | #1

On 20-03-20, 00:23, Dmitry Osipenko wrote:
> The interrupt is already disabled while interrupt handler is running, and
> thus, there is no need to save/restore the IRQ flags within the spinlock.

Applied both, thanks

Patch

diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index 4e295d121be6..26f427e02369 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -672,10 +672,9 @@  static void tegra_dma_tasklet(unsigned long data)
 static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
 {
 	struct tegra_dma_channel *tdc = dev_id;
-	unsigned long flags;
 	u32 status;
 
-	spin_lock_irqsave(&tdc->lock, flags);
+	spin_lock(&tdc->lock);
 
 	trace_tegra_dma_isr(&tdc->dma_chan, irq);
 	status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
@@ -683,11 +682,11 @@  static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
 		tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 		tdc->isr_handler(tdc, false);
 		tasklet_schedule(&tdc->tasklet);
-		spin_unlock_irqrestore(&tdc->lock, flags);
+		spin_unlock(&tdc->lock);
 		return IRQ_HANDLED;
 	}
 
-	spin_unlock_irqrestore(&tdc->lock, flags);
+	spin_unlock(&tdc->lock);
 	dev_info(tdc2dev(tdc), "Interrupt already served status 0x%08x\n",
 		 status);