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| author | Andrea Righi <arighi@nvidia.com> | 2025-02-25 12:37:42 +0300 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2025-02-25 21:35:53 +0300 |
| commit | fde7d64766c1142fe79507bbef4968cee274cc0b (patch) | |
| tree | ab6ff60f21eaffa765c993194665115eb047a081 | |
| parent | 0e9b4c10e833dbcfcdba63497463f1272c5efe4d (diff) | |
| download | linux-fde7d64766c1142fe79507bbef4968cee274cc0b.tar.xz | |
sched_ext: idle: Fix scx_bpf_pick_any_cpu_node() behavior
When %SCX_PICK_IDLE_IN_NODE is specified, scx_bpf_pick_any_cpu_node()
should always return a CPU from the specified node, regardless of its
idle state.
Also clarify this logic in the function documentation.
Fixes: 01059219b0cfd ("sched_ext: idle: Introduce node-aware idle cpu kfunc helpers")
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
| -rw-r--r-- | kernel/sched/ext_idle.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/kernel/sched/ext_idle.c b/kernel/sched/ext_idle.c index 759a06774b5b..dc40e0baf77c 100644 --- a/kernel/sched/ext_idle.c +++ b/kernel/sched/ext_idle.c @@ -1029,8 +1029,9 @@ __bpf_kfunc s32 scx_bpf_pick_idle_cpu(const struct cpumask *cpus_allowed, * empty. * * The search starts from @node and proceeds to other online NUMA nodes in - * order of increasing distance (unless SCX_PICK_IDLE_IN_NODE is specified, - * in which case the search is limited to the target @node). + * order of increasing distance (unless %SCX_PICK_IDLE_IN_NODE is specified, + * in which case the search is limited to the target @node, regardless of + * the CPU idle state). * * If ops.update_idle() is implemented and %SCX_OPS_KEEP_BUILTIN_IDLE is not * set, this function can't tell which CPUs are idle and will always pick any @@ -1049,7 +1050,10 @@ __bpf_kfunc s32 scx_bpf_pick_any_cpu_node(const struct cpumask *cpus_allowed, if (cpu >= 0) return cpu; - cpu = cpumask_any_distribute(cpus_allowed); + if (flags & SCX_PICK_IDLE_IN_NODE) + cpu = cpumask_any_and_distribute(cpumask_of_node(node), cpus_allowed); + else + cpu = cpumask_any_distribute(cpus_allowed); if (cpu < nr_cpu_ids) return cpu; else |