[PATCH sched_ext/for-6.14] sched_ext: idle: introduce check_builtin_idle_enabled() helper

Andrea Righi
2024-12-28T10:07:04Z

Minor refactoring to add a helper function for checking if the built-in
idle CPU selection policy is enabled.

Signed-off-by: Andrea Righi <arighi@nvidia.com>
---
kernel/sched/ext.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index 2d701203a3db..926579624c41 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -6297,6 +6297,15 @@ void __init init_sched_ext_class(void)

__bpf_kfunc_start_defs();

+static bool check_builtin_idle_enabled(void)
+{
+ if (static_branch_likely(&scx_builtin_idle_enabled))
+ return true;
+
+ scx_ops_error("built-in idle tracking is disabled");
+ return false;
+}
+
/**
* scx_bpf_select_cpu_dfl - The default implementation of ops.select_cpu()
* @p: task_struct to select a CPU for
@@ -6314,10 +6323,8 @@ __bpf_kfunc_start_defs();
__bpf_kfunc s32 scx_bpf_select_cpu_dfl(struct task_struct *p, s32 prev_cpu,
u64 wake_flags, bool *is_idle)
{
- if (!static_branch_likely(&scx_builtin_idle_enabled)) {
- scx_ops_error("built-in idle tracking is disabled");
+ if (!check_builtin_idle_enabled())
goto prev_cpu;
- }

if (!scx_kf_allowed(SCX_KF_SELECT_CPU))
goto prev_cpu;
@@ -7411,10 +7418,8 @@ __bpf_kfunc void scx_bpf_put_cpumask(const struct cpumask *cpumask)
*/
__bpf_kfunc const struct cpumask *scx_bpf_get_idle_cpumask(void)
{
- if (!static_branch_likely(&scx_builtin_idle_enabled)) {
- scx_ops_error("built-in idle tracking is disabled");
+ if (!check_builtin_idle_enabled())
return cpu_none_mask;
- }

#ifdef CONFIG_SMP
return idle_masks.cpu;
@@ -7432,10 +7437,8 @@ __bpf_kfunc const struct cpumask *scx_bpf_get_idle_cpumask(void)
*/
__bpf_kfunc const struct cpumask *scx_bpf_get_idle_smtmask(void)
{
- if (!static_branch_likely(&scx_builtin_idle_enabled)) {
- scx_ops_error("built-in idle tracking is disabled");
+ if (!check_builtin_idle_enabled())
return cpu_none_mask;
- }

#ifdef CONFIG_SMP
if (sched_smt_active())
@@ -7473,10 +7476,8 @@ __bpf_kfunc void scx_bpf_put_idle_cpumask(const struct cpumask *idle_mask)
*/
__bpf_kfunc bool scx_bpf_test_and_clear_cpu_idle(s32 cpu)
{
- if (!static_branch_likely(&scx_builtin_idle_enabled)) {
- scx_ops_error("built-in idle tracking is disabled");
+ if (!check_builtin_idle_enabled())
return false;
- }

if (ops_cpu_valid(cpu, NULL))
return test_and_clear_cpu_idle(cpu);
@@ -7506,10 +7507,8 @@ __bpf_kfunc bool scx_bpf_test_and_clear_cpu_idle(s32 cpu)
__bpf_kfunc s32 scx_bpf_pick_idle_cpu(const struct cpumask *cpus_allowed,
u64 flags)
{
- if (!static_branch_likely(&scx_builtin_idle_enabled)) {
- scx_ops_error("built-in idle tracking is disabled");
+ if (!check_builtin_idle_enabled())
return -EBUSY;
- }

return scx_pick_idle_cpu(cpus_allowed, flags);
}
--
2.47.1