diff options
| author | Cheng-Yang Chou <yphbchou0911@gmail.com> | 2026-03-23 23:17:33 +0800 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2026-03-23 07:45:08 -1000 |
| commit | cb251eae7b0aec8a7924fb27bcb5b0388a3706bc (patch) | |
| tree | 40d9ee858c3007a7707034f1ab746f307c6becd1 /tools/sched_ext/include | |
| parent | c50dcf533149e313a61d483769eb48682a1b0cdd (diff) | |
tools/sched_ext: Add scx_bpf_sub_dispatch() compat wrapper
Add a transparent compatibility wrapper for the scx_bpf_sub_dispatch()
kfunc in compat.bpf.h. This allows BPF schedulers using the sub-sched
dispatch feature to build and run on older kernels that lack the kfunc.
To avoid requiring code changes in individual schedulers, the
transparent wrapper pattern is used instead of a __COMPAT prefix. The
kfunc is declared with a ___compat suffix, while the static inline
wrapper retains the original scx_bpf_sub_dispatch() name.
When the kfunc is unavailable, the wrapper safely falls back to
returning false. This is acceptable because the dispatch path cannot
do anything useful without underlying sub-sched support anyway.
Tested scx_qmap on v6.14 successfully.
Signed-off-by: Cheng-Yang Chou <yphbchou0911@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'tools/sched_ext/include')
| -rw-r--r-- | tools/sched_ext/include/scx/common.bpf.h | 1 | ||||
| -rw-r--r-- | tools/sched_ext/include/scx/compat.bpf.h | 13 |
2 files changed, 13 insertions, 1 deletions
diff --git a/tools/sched_ext/include/scx/common.bpf.h b/tools/sched_ext/include/scx/common.bpf.h index a63a98a96b86..19459dedde41 100644 --- a/tools/sched_ext/include/scx/common.bpf.h +++ b/tools/sched_ext/include/scx/common.bpf.h @@ -101,7 +101,6 @@ struct rq *scx_bpf_locked_rq(void) __ksym; struct task_struct *scx_bpf_cpu_curr(s32 cpu) __ksym __weak; u64 scx_bpf_now(void) __ksym __weak; void scx_bpf_events(struct scx_event_stats *events, size_t events__sz) __ksym __weak; -bool scx_bpf_sub_dispatch(u64 cgroup_id) __ksym __weak; /* * Use the following as @it__iter when calling scx_bpf_dsq_move[_vtime]() from diff --git a/tools/sched_ext/include/scx/compat.bpf.h b/tools/sched_ext/include/scx/compat.bpf.h index 83b3425e63b2..654b566bd94a 100644 --- a/tools/sched_ext/include/scx/compat.bpf.h +++ b/tools/sched_ext/include/scx/compat.bpf.h @@ -108,6 +108,19 @@ static inline struct task_struct *__COMPAT_scx_bpf_dsq_peek(u64 dsq_id) return p; } +/* + * v7.1: scx_bpf_sub_dispatch() for sub-sched dispatch. Preserve until + * we drop the compat layer for older kernels that lack the kfunc. + */ +bool scx_bpf_sub_dispatch___compat(u64 cgroup_id) __ksym __weak; + +static inline bool scx_bpf_sub_dispatch(u64 cgroup_id) +{ + if (bpf_ksym_exists(scx_bpf_sub_dispatch___compat)) + return scx_bpf_sub_dispatch___compat(cgroup_id); + return false; +} + /** * __COMPAT_is_enq_cpu_selected - Test if SCX_ENQ_CPU_SELECTED is on * in a compatible way. We will preserve this __COMPAT helper until v6.16. |