From: Andrea Righi <arighi@xxxxxxxxxx>
commit 5f52bbf2f6e0997394cf9c449d44e1c80ff4282c upstream.
Introduce a new helper for BPF schedulers to determine whether a task
can migrate or not (supporting both SMP and UP systems).
Fixes: e9fe182772dc ("sched_ext: selftests/dsp_local_on: Fix sporadic failures")
Signed-off-by: Andrea Righi <arighi@xxxxxxxxxx>
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/sched_ext/include/scx/common.bpf.h | 11 +++++++++++
1 file changed, 11 insertions(+)
--- a/tools/sched_ext/include/scx/common.bpf.h
+++ b/tools/sched_ext/include/scx/common.bpf.h
@@ -333,6 +333,17 @@ static __always_inline const struct cpum
return (const struct cpumask *)mask;
}
+/*
+ * Return true if task @p cannot migrate to a different CPU, false
+ * otherwise.
+ */
+static inline bool is_migration_disabled(const struct task_struct *p)
+{
+ if (bpf_core_field_exists(p->migration_disabled))
+ return p->migration_disabled;
+ return false;
+}
+
/* rcu */
void bpf_rcu_read_lock(void) __ksym;
void bpf_rcu_read_unlock(void) __ksym;
Patches currently in stable-queue which might be from arighi@xxxxxxxxxx are
queue-6.12/sched_ext-validate-prev_cpu-in-scx_bpf_select_cpu_dfl.patch
queue-6.12/tools-sched_ext-add-helper-to-check-task-migration-state.patch
queue-6.12/sched_ext-selftests-dsp_local_on-fix-sporadic-failur.patch
queue-6.12/sched_ext-selftests-dsp_local_on-fix-selftest-on-up-systems.patch
