| Message ID | 1448104188-19836-1-git-send-email-lars@metafoo.de (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Sat, Nov 21, 2015 at 12:09:47PM +0100, Lars-Peter Clausen wrote: > Calling synchronize_irq() right before free_irq() is quite useless. On one > hand the IRQ can easily fire again before free_irq() is entered, on the > other hand free_irq() itself calls synchronize_irq() internally (in a race > condition free way), before any state associated with the IRQ is freed. > > Patch was generated using the following semantic patch: > // <smpl> > @@ > expression irq; > @@ > -synchronize_irq(irq); > free_irq(irq, ...); > // </smpl> > > Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> It sounds good. Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> > --- > drivers/dma/at_xdmac.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c > index 7f039de..d02276f 100644 > --- a/drivers/dma/at_xdmac.c > +++ b/drivers/dma/at_xdmac.c > @@ -1995,8 +1995,6 @@ static int at_xdmac_remove(struct platform_device *pdev) > dma_async_device_unregister(&atxdmac->dma); > clk_disable_unprepare(atxdmac->clk); > > - synchronize_irq(atxdmac->irq); > - > free_irq(atxdmac->irq, atxdmac->dma.dev); > > for (i = 0; i < atxdmac->dma.chancnt; i++) { > -- > 2.1.4 > -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Nov 21, 2015 at 12:09:47PM +0100, Lars-Peter Clausen wrote: > Calling synchronize_irq() right before free_irq() is quite useless. On one > hand the IRQ can easily fire again before free_irq() is entered, on the > other hand free_irq() itself calls synchronize_irq() internally (in a race > condition free way), before any state associated with the IRQ is freed. > > Patch was generated using the following semantic patch: > // <smpl> > @@ > expression irq; > @@ > -synchronize_irq(irq); > free_irq(irq, ...); > // </smpl> Applied, both Thanks
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 7f039de..d02276f 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -1995,8 +1995,6 @@ static int at_xdmac_remove(struct platform_device *pdev) dma_async_device_unregister(&atxdmac->dma); clk_disable_unprepare(atxdmac->clk); - synchronize_irq(atxdmac->irq); - free_irq(atxdmac->irq, atxdmac->dma.dev); for (i = 0; i < atxdmac->dma.chancnt; i++) {
Calling synchronize_irq() right before free_irq() is quite useless. On one hand the IRQ can easily fire again before free_irq() is entered, on the other hand free_irq() itself calls synchronize_irq() internally (in a race condition free way), before any state associated with the IRQ is freed. Patch was generated using the following semantic patch: // <smpl> @@ expression irq; @@ -synchronize_irq(irq); free_irq(irq, ...); // </smpl> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> --- drivers/dma/at_xdmac.c | 2 -- 1 file changed, 2 deletions(-)