kernel: trace: preemptirq_delay_test: use offstack cpu mask

A CPU mask on the stack is broken for large values of CONFIG_NR_CPUS:

kernel/trace/preemptirq_delay_test.c: In function ‘preemptirq_delay_run’:
kernel/trace/preemptirq_delay_test.c:143:1: error: the frame size of 8512 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]

Fall back to dynamic allocation here.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Song Chen <chensong_2000@189.cn>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250620111215.3365305-1-arnd@kernel.org
Fixes: 4b9091e1c1 ("kernel: trace: preemptirq_delay_test: add cpu affinity")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Arnd Bergmann 2025-06-20 13:12:12 +02:00 committed by Steven Rostedt (Google)
parent 3aceaa539c
commit adc353c0bf
1 changed files with 9 additions and 4 deletions

View File

@ -117,12 +117,15 @@ static int preemptirq_delay_run(void *data)
{ {
int i; int i;
int s = MIN(burst_size, NR_TEST_FUNCS); int s = MIN(burst_size, NR_TEST_FUNCS);
struct cpumask cpu_mask; cpumask_var_t cpu_mask;
if (!alloc_cpumask_var(&cpu_mask, GFP_KERNEL))
return -ENOMEM;
if (cpu_affinity > -1) { if (cpu_affinity > -1) {
cpumask_clear(&cpu_mask); cpumask_clear(cpu_mask);
cpumask_set_cpu(cpu_affinity, &cpu_mask); cpumask_set_cpu(cpu_affinity, cpu_mask);
if (set_cpus_allowed_ptr(current, &cpu_mask)) if (set_cpus_allowed_ptr(current, cpu_mask))
pr_err("cpu_affinity:%d, failed\n", cpu_affinity); pr_err("cpu_affinity:%d, failed\n", cpu_affinity);
} }
@ -139,6 +142,8 @@ static int preemptirq_delay_run(void *data)
__set_current_state(TASK_RUNNING); __set_current_state(TASK_RUNNING);
free_cpumask_var(cpu_mask);
return 0; return 0;
} }