[PATCH v2 6/7] sparc/leon: Remove on-stack cpumask var

From: Dawei Li
Date: Sat Apr 20 2024 - 01:17:49 EST


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.

Use cpumask_subset() and cpumask_first_and() to avoid the need for a
temporary cpumask on the stack.

Signed-off-by: Dawei Li <dawei.li@xxxxxxxxxxxx>
---
arch/sparc/kernel/leon_kernel.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/sparc/kernel/leon_kernel.c b/arch/sparc/kernel/leon_kernel.c
index 4c61da491fee..0070655041bb 100644
--- a/arch/sparc/kernel/leon_kernel.c
+++ b/arch/sparc/kernel/leon_kernel.c
@@ -106,13 +106,10 @@ unsigned long leon_get_irqmask(unsigned int irq)
#ifdef CONFIG_SMP
static int irq_choose_cpu(const struct cpumask *affinity)
{
- cpumask_t mask;
+ unsigned int cpu = cpumask_first_and(affinity, cpu_online_mask);

- cpumask_and(&mask, cpu_online_mask, affinity);
- if (cpumask_equal(&mask, cpu_online_mask) || cpumask_empty(&mask))
- return boot_cpu_id;
- else
- return cpumask_first(&mask);
+ return cpumask_subset(cpu_online_mask, affinity) || cpu >= nr_cpu_ids ?
+ boot_cpu_id : cpu;
}
#else
#define irq_choose_cpu(affinity) boot_cpu_id
--
2.27.0