From: Tejun Heo Date: Sat, 7 Mar 2026 15:29:49 +0000 (-1000) Subject: sched_ext: Relocate scx_bpf_task_cgroup() and its BTF_ID to the end of kfunc section X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=26b9c7c70027f011a5f39cef9c3cf44539310a6d;p=thirdparty%2Flinux.git sched_ext: Relocate scx_bpf_task_cgroup() and its BTF_ID to the end of kfunc section Move scx_bpf_task_cgroup() kfunc definition and its BTF_ID entry to the end of the kfunc section before __bpf_kfunc_end_defs() for cleaner code organization. No functional changes. Signed-off-by: Tejun Heo Reviewed-by: Emil Tsalapatis Reviewed-by: Daniel Jordan Reviewed-by: Andrea Righi --- diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 47f65041b363d..fa8968164fd28 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -8627,43 +8627,6 @@ __bpf_kfunc struct task_struct *scx_bpf_cpu_curr(s32 cpu, const struct bpf_prog_ return rcu_dereference(cpu_rq(cpu)->curr); } -/** - * scx_bpf_task_cgroup - Return the sched cgroup of a task - * @p: task of interest - * @aux: implicit BPF argument to access bpf_prog_aux hidden from BPF progs - * - * @p->sched_task_group->css.cgroup represents the cgroup @p is associated with - * from the scheduler's POV. SCX operations should use this function to - * determine @p's current cgroup as, unlike following @p->cgroups, - * @p->sched_task_group is protected by @p's rq lock and thus atomic w.r.t. all - * rq-locked operations. Can be called on the parameter tasks of rq-locked - * operations. The restriction guarantees that @p's rq is locked by the caller. - */ -#ifdef CONFIG_CGROUP_SCHED -__bpf_kfunc struct cgroup *scx_bpf_task_cgroup(struct task_struct *p, - const struct bpf_prog_aux *aux) -{ - struct task_group *tg = p->sched_task_group; - struct cgroup *cgrp = &cgrp_dfl_root.cgrp; - struct scx_sched *sch; - - guard(rcu)(); - - sch = scx_prog_sched(aux); - if (unlikely(!sch)) - goto out; - - if (!scx_kf_allowed_on_arg_tasks(sch, __SCX_KF_RQ_LOCKED, p)) - goto out; - - cgrp = tg_cgrp(tg); - -out: - cgroup_get(cgrp); - return cgrp; -} -#endif - /** * scx_bpf_now - Returns a high-performance monotonically non-decreasing * clock for the current CPU. The clock returned is in nanoseconds. @@ -8778,6 +8741,43 @@ __bpf_kfunc void scx_bpf_events(struct scx_event_stats *events, memcpy(events, &e_sys, events__sz); } +#ifdef CONFIG_CGROUP_SCHED +/** + * scx_bpf_task_cgroup - Return the sched cgroup of a task + * @p: task of interest + * @aux: implicit BPF argument to access bpf_prog_aux hidden from BPF progs + * + * @p->sched_task_group->css.cgroup represents the cgroup @p is associated with + * from the scheduler's POV. SCX operations should use this function to + * determine @p's current cgroup as, unlike following @p->cgroups, + * @p->sched_task_group is protected by @p's rq lock and thus atomic w.r.t. all + * rq-locked operations. Can be called on the parameter tasks of rq-locked + * operations. The restriction guarantees that @p's rq is locked by the caller. + */ +__bpf_kfunc struct cgroup *scx_bpf_task_cgroup(struct task_struct *p, + const struct bpf_prog_aux *aux) +{ + struct task_group *tg = p->sched_task_group; + struct cgroup *cgrp = &cgrp_dfl_root.cgrp; + struct scx_sched *sch; + + guard(rcu)(); + + sch = scx_prog_sched(aux); + if (unlikely(!sch)) + goto out; + + if (!scx_kf_allowed_on_arg_tasks(sch, __SCX_KF_RQ_LOCKED, p)) + goto out; + + cgrp = tg_cgrp(tg); + +out: + cgroup_get(cgrp); + return cgrp; +} +#endif /* CONFIG_CGROUP_SCHED */ + __bpf_kfunc_end_defs(); BTF_KFUNCS_START(scx_kfunc_ids_any) @@ -8807,11 +8807,11 @@ BTF_ID_FLAGS(func, scx_bpf_task_cpu, KF_RCU) BTF_ID_FLAGS(func, scx_bpf_cpu_rq, KF_IMPLICIT_ARGS) BTF_ID_FLAGS(func, scx_bpf_locked_rq, KF_IMPLICIT_ARGS | KF_RET_NULL) BTF_ID_FLAGS(func, scx_bpf_cpu_curr, KF_IMPLICIT_ARGS | KF_RET_NULL | KF_RCU_PROTECTED) +BTF_ID_FLAGS(func, scx_bpf_now) +BTF_ID_FLAGS(func, scx_bpf_events) #ifdef CONFIG_CGROUP_SCHED BTF_ID_FLAGS(func, scx_bpf_task_cgroup, KF_IMPLICIT_ARGS | KF_RCU | KF_ACQUIRE) #endif -BTF_ID_FLAGS(func, scx_bpf_now) -BTF_ID_FLAGS(func, scx_bpf_events) BTF_KFUNCS_END(scx_kfunc_ids_any) static const struct btf_kfunc_id_set scx_kfunc_set_any = {