diff options
Diffstat (limited to 'drivers/uio/uio_dmem_genirq.c')
| -rw-r--r-- | drivers/uio/uio_dmem_genirq.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/uio/uio_dmem_genirq.c b/drivers/uio/uio_dmem_genirq.c index 44858f70f5f5..39dbd8c56249 100644 --- a/drivers/uio/uio_dmem_genirq.c +++ b/drivers/uio/uio_dmem_genirq.c @@ -110,8 +110,10 @@ static irqreturn_t uio_dmem_genirq_handler(int irq, struct uio_info *dev_info) * remember the state so we can allow user space to enable it later. */ + spin_lock(&priv->lock); if (!test_and_set_bit(0, &priv->flags)) disable_irq_nosync(irq); + spin_unlock(&priv->lock); return IRQ_HANDLED; } @@ -125,20 +127,19 @@ static int uio_dmem_genirq_irqcontrol(struct uio_info *dev_info, s32 irq_on) * in the interrupt controller, but keep track of the * state to prevent per-irq depth damage. * - * Serialize this operation to support multiple tasks. + * Serialize this operation to support multiple tasks and concurrency + * with irq handler on SMP systems. */ spin_lock_irqsave(&priv->lock, flags); if (irq_on) { if (test_and_clear_bit(0, &priv->flags)) enable_irq(dev_info->irq); - spin_unlock_irqrestore(&priv->lock, flags); } else { - if (!test_and_set_bit(0, &priv->flags)) { - spin_unlock_irqrestore(&priv->lock, flags); - disable_irq(dev_info->irq); - } + if (!test_and_set_bit(0, &priv->flags)) + disable_irq_nosync(dev_info->irq); } + spin_unlock_irqrestore(&priv->lock, flags); return 0; } |