| Message ID | 1454964073-25108-1-git-send-email-lars@metafoo.de (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Kalle Valo |
| Headers | show |
On Mon, 8 Feb 2016 21:41:12 +0100 Lars-Peter Clausen <lars@metafoo.de> 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, Well, that depends on whether the interrupt is shared and whether we disabled the interrupt mask inside of the device (which we did). > 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. Ok, fair enough.
> 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> Thanks, 2 patches applied to wireless-drivers-next.git: 10fbc7cf031d b43: Remove unnecessary synchronize_irq() before free_irq() 400b43c58269 rtlwifi: Remove unnecessary synchronize_irq() before free_irq() Kalle Valo -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/wireless/broadcom/b43/main.c b/drivers/net/wireless/broadcom/b43/main.c index c279211..72380af 100644 --- a/drivers/net/wireless/broadcom/b43/main.c +++ b/drivers/net/wireless/broadcom/b43/main.c @@ -4375,12 +4375,10 @@ redo: /* Synchronize and free the interrupt handlers. Unlock to avoid deadlocks. */ orig_dev = dev; mutex_unlock(&wl->mutex); - if (b43_bus_host_is_sdio(dev->dev)) { + if (b43_bus_host_is_sdio(dev->dev)) b43_sdio_free_irq(dev); - } else { - synchronize_irq(dev->dev->irq); + else free_irq(dev->dev->irq, dev); - } mutex_lock(&wl->mutex); dev = wl->current_dev; if (!dev)
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/net/wireless/broadcom/b43/main.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)