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| author | Radu Rendec <rrendec@redhat.com> | 2025-11-28 16:20:53 -0500 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2025-12-15 22:30:48 +0100 |
| commit | fcc1d0dabdb65ca069f77e5b76d3b20277be4a15 (patch) | |
| tree | ac760b3a7d663e14dc03e15be246394e9f6cc425 /include/linux/irq.h | |
| parent | 0317e0aba5d41ae5e974026bf96899d9ae4bcbdb (diff) | |
| download | linux-next-fcc1d0dabdb65ca069f77e5b76d3b20277be4a15.tar.gz linux-next-fcc1d0dabdb65ca069f77e5b76d3b20277be4a15.zip | |
genirq: Add interrupt redirection infrastructure
Add infrastructure to redirect interrupt handler execution to a
different CPU when the current CPU is not part of the interrupt's CPU
affinity mask.
This is primarily aimed at (de)multiplexed interrupts, where the child
interrupt handler runs in the context of the parent interrupt handler,
and therefore CPU affinity control for the child interrupt is typically
not available.
With the new infrastructure, the child interrupt is allowed to freely
change its affinity setting, independently of the parent. If the
interrupt handler happens to be triggered on an "incompatible" CPU (a
CPU that's not part of the child interrupt's affinity mask), the handler
is redirected and runs in IRQ work context on a "compatible" CPU.
No functional change is being made to any existing irqchip driver, and
irqchip drivers must be explicitly modified to use the newly added
infrastructure to support interrupt redirection.
Originally-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Radu Rendec <rrendec@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/linux-pci/878qpg4o4t.ffs@tglx/
Link: https://patch.msgid.link/20251128212055.1409093-2-rrendec@redhat.com
Diffstat (limited to 'include/linux/irq.h')
| -rw-r--r-- | include/linux/irq.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/linux/irq.h b/include/linux/irq.h index 4a9f1d7b08c3..41d5bc53eefc 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -459,6 +459,8 @@ static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) * checks against the supplied affinity mask are not * required. This is used for CPU hotplug where the * target CPU is not yet set in the cpu_online_mask. + * @irq_pre_redirect: Optional function to be invoked before redirecting + * an interrupt via irq_work. Called only on CONFIG_SMP. * @irq_retrigger: resend an IRQ to the CPU * @irq_set_type: set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ * @irq_set_wake: enable/disable power-management wake-on of an IRQ @@ -503,6 +505,7 @@ struct irq_chip { void (*irq_eoi)(struct irq_data *data); int (*irq_set_affinity)(struct irq_data *data, const struct cpumask *dest, bool force); + void (*irq_pre_redirect)(struct irq_data *data); int (*irq_retrigger)(struct irq_data *data); int (*irq_set_type)(struct irq_data *data, unsigned int flow_type); int (*irq_set_wake)(struct irq_data *data, unsigned int on); @@ -687,6 +690,13 @@ extern int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, extern int irq_chip_set_type_parent(struct irq_data *data, unsigned int type); extern int irq_chip_request_resources_parent(struct irq_data *data); extern void irq_chip_release_resources_parent(struct irq_data *data); +#ifdef CONFIG_SMP +void irq_chip_pre_redirect_parent(struct irq_data *data); +#endif +#endif + +#ifdef CONFIG_SMP +int irq_chip_redirect_set_affinity(struct irq_data *data, const struct cpumask *dest, bool force); #endif /* Disable or mask interrupts during a kernel kexec */ |