Commit fcb8af4c authored by Dawei Li's avatar Dawei Li Committed by Thomas Gleixner
Browse files

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



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: default avatarDawei Li <dawei.li@shingroup.cn>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240416085454.3547175-4-dawei.li@shingroup.cn
parent 6a9a52f7

drivers/irqchip/irq-gic-v3-its.c

+10 −5
Original line number Diff line number Diff line
@@ -3826,9 +3826,9 @@ static int its_vpe_set_affinity(struct irq_data *d, 
				bool force)

{

	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;

	int from, cpu;



	/*

	 * 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

	 * affinity, pick this one. Otherwise, any CPU will do.

	 */

	if (table_mask && cpumask_and(&common, mask_val, table_mask))

		cpu = cpumask_test_cpu(from, &common) ? from : cpumask_first(&common);

	else

	if (table_mask)

		cpu = cpumask_any_and(mask_val, table_mask);

	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);

	}



	if (from == cpu)

		goto out;