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irqchip/gic-v3-its: Avoid explicit cpumask allocation on stack

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In general it's preferable to avoid placing cpumasks on the stack, as
for large values of NR_CPUS these can consume significant amounts of
stack space and make stack overflows more likely.

Remove cpumask var on stack and use cpumask_any_and() to address it.

Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240416085454.3547175-4-dawei.li@shingroup.cn
This commit is contained in:
Dawei Li 2024-04-16 16:54:50 +08:00 committed by Thomas Gleixner
parent 6a9a52f74e
commit fcb8af4cbc
1 changed files with 10 additions and 5 deletions
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15
drivers/irqchip/irq-gic-v3-its.c
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@ -3826,9 +3826,9 @@ static int its_vpe_set_affinity(struct irq_data *d,
bool force) bool force)
{ {
struct its_vpe *vpe = irq_data_get_irq_chip_data(d); struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
struct cpumask common, *table_mask; unsigned int from, cpu = nr_cpu_ids;
struct cpumask *table_mask;
unsigned long flags; unsigned long flags;
int from, cpu;
/* /*
* Changing affinity is mega expensive, so let's be as lazy as * Changing affinity is mega expensive, so let's be as lazy as
@ -3850,10 +3850,15 @@ static int its_vpe_set_affinity(struct irq_data *d,
* If we are offered another CPU in the same GICv4.1 ITS * If we are offered another CPU in the same GICv4.1 ITS
* affinity, pick this one. Otherwise, any CPU will do. * affinity, pick this one. Otherwise, any CPU will do.
*/ */
if (table_mask && cpumask_and(&common, mask_val, table_mask)) if (table_mask)
cpu = cpumask_test_cpu(from, &common) ? from : cpumask_first(&common); cpu = cpumask_any_and(mask_val, table_mask);
else if (cpu < nr_cpu_ids) {
if (cpumask_test_cpu(from, mask_val) &&
cpumask_test_cpu(from, table_mask))
cpu = from;
} else {
cpu = cpumask_first(mask_val); cpu = cpumask_first(mask_val);
}
if (from == cpu) if (from == cpu)
goto out; goto out;