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parisc: Remove unnecessary NULL check of the kstat_irqs field

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The kstat_irqs field of struct irq_desc is used to store a per-cpu count
of interrupt events. It is initialized in init_desc(), along with all
the other fields in struct irq_desc that need explicit initialization,
and therefore it's always available (non-NULL) for any valid interrupt
descriptor.

On parisc, CONFIG_SPARSE_IRQ is disabled, interrupt descriptors are
allocated statically in the irq_desc[] array, and kstat_irqs is
initialized implicitly to NULL. The kstat_irqs field is initialized
later, for all descriptors, via start_kernel() -> early_irq_init() ->
init_desc().

smp_boot_one_cpu() is used only for CPU hotplugging. On a SMP system,
the boot CPU initializes the interrupt descriptors as described above,
and smp_boot_one_cpu() is called later, for the secondary CPU(s).

A previous change made similar changes across the generic interrupt code in
kernel/irq/irqdesc.c, and provides a more detailed explanation of why
kstat_irqs is guaranteed to be non-NULL.

Signed-off-by: Radu Rendec <radu@rendec.net>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260705210951.2717741-3-radu@rendec.net
This commit is contained in:
Radu Rendec 2026-07-05 17:09:51 -04:00 committed by Thomas Gleixner
parent 57d1220979
commit 2c27d9b154
1 changed files with 1 additions and 1 deletions
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2
arch/parisc/kernel/smp.c
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@ -343,7 +343,7 @@ static int smp_boot_one_cpu(int cpuid, struct task_struct *idle)
for (i = 0; i < NR_IRQS; i++) {
struct irq_desc *desc = irq_to_desc(i);
if (desc && desc->kstat_irqs)
if (desc)
*per_cpu_ptr(desc->kstat_irqs, cpuid) = (struct irqstat) { };
}
#endif