Messages in this thread | | | Subject | Re: [PATCH 01/11] genirq: Add fasteoi IPI flow | From | Florian Fainelli <> | Date | Tue, 19 May 2020 12:47:24 -0700 |
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On 5/19/2020 9:17 AM, Marc Zyngier wrote: > For irqchips using the fasteoi flow, IPIs are a bit special. > > They need to be EOId early (before calling the handler), as > funny things may happen in the handler (they do not necessarily > behave like a normal interrupt), and that the arch code is > already handling the stats. > > Signed-off-by: Marc Zyngier <maz@kernel.org> > --- > include/linux/irq.h | 1 + > kernel/irq/chip.c | 26 ++++++++++++++++++++++++++ > 2 files changed, 27 insertions(+) > > diff --git a/include/linux/irq.h b/include/linux/irq.h > index 8d5bc2c237d7..726f94d8b8cc 100644 > --- a/include/linux/irq.h > +++ b/include/linux/irq.h > @@ -621,6 +621,7 @@ static inline int irq_set_parent(int irq, int parent_irq) > */ > extern void handle_level_irq(struct irq_desc *desc); > extern void handle_fasteoi_irq(struct irq_desc *desc); > +extern void handle_percpu_devid_fasteoi_ipi(struct irq_desc *desc); > extern void handle_edge_irq(struct irq_desc *desc); > extern void handle_edge_eoi_irq(struct irq_desc *desc); > extern void handle_simple_irq(struct irq_desc *desc); > diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c > index 41e7e37a0928..7b0b789cfed4 100644 > --- a/kernel/irq/chip.c > +++ b/kernel/irq/chip.c > @@ -955,6 +955,32 @@ void handle_percpu_devid_irq(struct irq_desc *desc) > chip->irq_eoi(&desc->irq_data); > } > > +/** > + * handle_percpu_devid_fasteoi_ipi - Per CPU local IPI handler with per cpu > + * dev ids > + * @desc: the interrupt description structure for this irq > + * > + * The biggest differences with the IRQ version are that: > + * - the interrupt is EOIed early, as the IPI could result in a context > + * switch, and we need to make sure the IPI can fire again > + * - Stats are usually handled at the architecture level, so we ignore them > + * here > + */ > +void handle_percpu_devid_fasteoi_ipi(struct irq_desc *desc) > +{ > + struct irq_chip *chip = irq_desc_get_chip(desc); > + struct irqaction *action = desc->action; > + unsigned int irq = irq_desc_get_irq(desc); > + irqreturn_t res;
Should not this have a:
if (!irq_settings_is_no_accounting(desc)) __kstat_incr_irqs_this_cpu(desc);
here in case you are using that handler with a SGI interrupt which is not used as an IPI?
> + > + if (chip->irq_eoi) > + chip->irq_eoi(&desc->irq_data); > + > + trace_irq_handler_entry(irq, action); > + res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id)); > + trace_irq_handler_exit(irq, action, res); > +} > + > /** > * handle_percpu_devid_fasteoi_nmi - Per CPU local NMI handler with per cpu > * dev ids >
-- Florian
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