Provide generic_handle_domain_irq_safe() which can used from any context.
This similar to commit
509853f9e1e7b ("genirq: Provide generic_handle_irq_safe()")
but this time for the irq-domains interface. It has been reported for
the amd-pinctrl driver via bugzilla
https://bugzilla.kernel.org/show_bug.cgi?id=215954
I looked around and added a few users so it is not just one user API :)
Instead of generic_handle_irq(irq_find_mapping)) one can use
generic_handle_domain_irq().
The problem with generic_handle_domain_irq() is that with `threadirqs'
it will trigger "WARN_ON_ONCE(!in_hardirq())". That interrupt handler
can't be marked non-threaded because it is a shared handler (it is
marked as such and I can't tell the interrupt can be really shared on
the system).
Ignoring the just mentioned warning, on PREEMPT_RT the threaded handler
is invoked with enabled interrupts leading other problems.
Do we do this?
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
---
drivers/bcma/driver_gpio.c | 2 +-
drivers/gpio/gpio-mlxbf2.c | 6 ++----
drivers/pinctrl/pinctrl-amd.c | 2 +-
drivers/platform/x86/intel/int0002_vgpio.c | 3 +--
drivers/ssb/driver_gpio.c | 6 ++++--
include/linux/irqdesc.h | 1 +
kernel/irq/irqdesc.c | 24 ++++++++++++++++++++++
7 files changed, 34 insertions(+), 10 deletions(-)
diff --git a/drivers/bcma/driver_gpio.c b/drivers/bcma/driver_gpio.c
index 1e74ec1c7f231..ed2730a21e7c4 100644
--- a/drivers/bcma/driver_gpio.c
+++ b/drivers/bcma/driver_gpio.c
@@ -113,7 +113,7 @@ static irqreturn_t bcma_gpio_irq_handler(int irq, void *dev_id)
return IRQ_NONE;
for_each_set_bit(gpio, &irqs, gc->ngpio)
- generic_handle_irq(irq_find_mapping(gc->irq.domain, gpio));
+ generic_handle_domain_irq_safe(gc->irq.domain, gpio);
bcma_chipco_gpio_polarity(cc, irqs, val & irqs);
return IRQ_HANDLED;
diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
index 3d89912a05b87..d4916f32fee73 100644
--- a/drivers/gpio/gpio-mlxbf2.c
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -273,10 +273,8 @@ static irqreturn_t mlxbf2_gpio_irq_handler(int irq, void *ptr)
pending = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_CAUSE_EVTEN0);
writel(pending, gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE);
- for_each_set_bit(level, &pending, gc->ngpio) {
- int gpio_irq = irq_find_mapping(gc->irq.domain, level);
- generic_handle_irq(gpio_irq);
- }
+ for_each_set_bit(level, &pending, gc->ngpio)
+ generic_handle_domain_irq_safe(gc->irq.domain, level);
return IRQ_RETVAL(pending);
}
diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
index 1a7d686494ffb..ce6fa6a76d1f6 100644
--- a/drivers/pinctrl/pinctrl-amd.c
+++ b/drivers/pinctrl/pinctrl-amd.c
@@ -638,7 +638,7 @@ static bool do_amd_gpio_irq_handler(int irq, void *dev_id)
if (!(regval & PIN_IRQ_PENDING) ||
!(regval & BIT(INTERRUPT_MASK_OFF)))
continue;
- generic_handle_domain_irq(gc->irq.domain, irqnr + i);
+ generic_handle_domain_irq_safe(gc->irq.domain, irqnr + i);
/* Clear interrupt.
* We must read the pin register again, in case the
diff --git a/drivers/platform/x86/intel/int0002_vgpio.c b/drivers/platform/x86/intel/int0002_vgpio.c
index 617dbf98980ec..97cfbc520a02c 100644
--- a/drivers/platform/x86/intel/int0002_vgpio.c
+++ b/drivers/platform/x86/intel/int0002_vgpio.c
@@ -125,8 +125,7 @@ static irqreturn_t int0002_irq(int irq, void *data)
if (!(gpe_sts_reg & GPE0A_PME_B0_STS_BIT))
return IRQ_NONE;
- generic_handle_irq(irq_find_mapping(chip->irq.domain,
- GPE0A_PME_B0_VIRT_GPIO_PIN));
+ generic_handle_domain_irq_safe(chip->irq.domain, GPE0A_PME_B0_VIRT_GPIO_PIN);
pm_wakeup_hard_event(chip->parent);
diff --git a/drivers/ssb/driver_gpio.c b/drivers/ssb/driver_gpio.c
index 2de3896489c84..897cb8db5084f 100644
--- a/drivers/ssb/driver_gpio.c
+++ b/drivers/ssb/driver_gpio.c
@@ -132,7 +132,8 @@ static irqreturn_t ssb_gpio_irq_chipco_handler(int irq, void *dev_id)
return IRQ_NONE;
for_each_set_bit(gpio, &irqs, bus->gpio.ngpio)
- generic_handle_irq(ssb_gpio_to_irq(&bus->gpio, gpio));
+ generic_handle_domain_irq_safe(bus->irq_domain, gpio);
+
ssb_chipco_gpio_polarity(chipco, irqs, val & irqs);
return IRQ_HANDLED;
@@ -330,7 +331,8 @@ static irqreturn_t ssb_gpio_irq_extif_handler(int irq, void *dev_id)
return IRQ_NONE;
for_each_set_bit(gpio, &irqs, bus->gpio.ngpio)
- generic_handle_irq(ssb_gpio_to_irq(&bus->gpio, gpio));
+ generic_handle_domain_irq_safe(bus->irq_domain, gpio);
+
ssb_extif_gpio_polarity(extif, irqs, val & irqs);
return IRQ_HANDLED;
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index a77584593f7d1..98253955e2ae7 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -169,6 +169,7 @@ int generic_handle_irq_safe(unsigned int irq);
* conversion failed.
*/
int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq);
+int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq);
int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq);
#endif
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 0099b87dd8530..48c34d47255cc 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -706,6 +706,30 @@ int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
}
EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
+ /**
+ * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
+ * to a domain from any context.
+ * @domain: The domain where to perform the lookup
+ * @hwirq: The HW irq number to convert to a logical one
+ *
+ * Returns: 0 on success, a negative value on error.
+ *
+ * This function can be called from any context (IRQ or process context). It
+ * will report an error if not invoked from IRQ context and the irq has been
+ * marked to enforce IRQ-context only.
+ */
+int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
+{
+ unsigned long flags;
+ int ret;
+
+ local_irq_save(flags);
+ ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
+ local_irq_restore(flags);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
+
/**
* generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
* to a domain.
--
2.36.0
On Mon, May 09, 2022 at 04:04:08PM +0200, Sebastian Andrzej Siewior wrote:
> The problem with generic_handle_domain_irq() is that with `threadirqs'
> it will trigger "WARN_ON_ONCE(!in_hardirq())".
Now silenced by:
https://git.kernel.org/linus/792ea6a074ae
> +int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
> +{
> + unsigned long flags;
> + int ret;
> +
> + local_irq_save(flags);
> + ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
> + local_irq_restore(flags);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
AFAICS you don't need to disable hardirqs at least for the "threadirqs"
case because irq_forced_thread_fn() already does that.
> drivers/bcma/driver_gpio.c | 2 +-
> drivers/gpio/gpio-mlxbf2.c | 6 ++----
> drivers/pinctrl/pinctrl-amd.c | 2 +-
> drivers/platform/x86/intel/int0002_vgpio.c | 3 +--
> drivers/ssb/driver_gpio.c | 6 ++++--
From a quick look, the proper solution for all of those drivers is
probably to just add IRQF_NO_THREAD and be done with it.
Thanks,
Lukas
On 2022-05-16 12:18:14 [+0200], Lukas Wunner wrote:
> On Mon, May 09, 2022 at 04:04:08PM +0200, Sebastian Andrzej Siewior wrote:
> > The problem with generic_handle_domain_irq() is that with `threadirqs'
> > it will trigger "WARN_ON_ONCE(!in_hardirq())".
>
> Now silenced by:
> https://git.kernel.org/linus/792ea6a074ae
>
>
> > +int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
> > +{
> > + unsigned long flags;
> > + int ret;
> > +
> > + local_irq_save(flags);
> > + ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
> > + local_irq_restore(flags);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
>
> AFAICS you don't need to disable hardirqs at least for the "threadirqs"
> case because irq_forced_thread_fn() already does that.
PREEMPT_RT does not disable interrupts. Also completions in softirq
won't disable interrupts.
>
> > drivers/bcma/driver_gpio.c | 2 +-
> > drivers/gpio/gpio-mlxbf2.c | 6 ++----
> > drivers/pinctrl/pinctrl-amd.c | 2 +-
> > drivers/platform/x86/intel/int0002_vgpio.c | 3 +--
> > drivers/ssb/driver_gpio.c | 6 ++++--
>
> From a quick look, the proper solution for all of those drivers is
> probably to just add IRQF_NO_THREAD and be done with it.
I think I mentioned that part in the commit description: IRQF_NO_THREAD
must be specified by all handlers of a shared interrupt. It is an option
for the handler that owns an interrupt exclusive.
> Thanks,
>
> Lukas
Sebastian