diff options
| author |   Thomas Gleixner <tglx@linutronix.de> | 2015-10-09 23:28:58 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2015-10-11 11:33:42 +0200 |
| commit | e9849777d0e27cdd2902805be51da73e7c79578c (patch) | |
| tree | 398bab5d6a91973d2e8a281bae6dff8ebd57ac8b /include/linux/irq.h | |
| parent | Merge tag 'gic-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core (diff) | |
| download | wireguard-linux-e9849777d0e27cdd2902805be51da73e7c79578c.tar.xz wireguard-linux-e9849777d0e27cdd2902805be51da73e7c79578c.zip | |
genirq: Add flag to force mask in disable_irq[_nosync]()
If an irq chip does not implement the irq_disable callback, then we
use a lazy approach for disabling the interrupt. That means that the
interrupt is marked disabled, but the interrupt line is not
immediately masked in the interrupt chip. It only becomes masked if
the interrupt is raised while it's marked disabled. We use this to avoid
possibly expensive mask/unmask operations for common case operations.
Unfortunately there are devices which do not allow the interrupt to be
disabled easily at the device level. They are forced to use
disable_irq_nosync(). This can result in taking each interrupt twice.
Instead of enforcing the non lazy mode on all interrupts of a irq
chip, provide a settings flag, which can be set by the driver for that
particular interrupt line.
Reported-and-tested-by: Duc Dang <dhdang@apm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1510092348370.6097@nanos
Diffstat (limited to 'include/linux/irq.h')
| -rw-r--r-- | include/linux/irq.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/include/linux/irq.h b/include/linux/irq.h index ba72b60b57b1..3c1c96786248 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -72,6 +72,7 @@ enum irqchip_irq_state; * IRQ_IS_POLLED - Always polled by another interrupt. Exclude * it from the spurious interrupt detection * mechanism and from core side polling. + * IRQ_DISABLE_UNLAZY - Disable lazy irq disable */ enum { IRQ_TYPE_NONE = 0x00000000, @@ -97,13 +98,14 @@ enum { IRQ_NOTHREAD = (1 << 16), IRQ_PER_CPU_DEVID = (1 << 17), IRQ_IS_POLLED = (1 << 18), + IRQ_DISABLE_UNLAZY = (1 << 19), }; #define IRQF_MODIFY_MASK \ (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \ IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \ IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \ - IRQ_IS_POLLED) + IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY) #define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING) |