From: Tejun Heo Date: Sat, 7 Mar 2026 15:29:49 +0000 (-1000) Subject: sched_ext: Change find_global_dsq() to take CPU number instead of task X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=053d27fba582b6c33531aa4d4f7d4e7ee73f193a;p=thirdparty%2Flinux.git sched_ext: Change find_global_dsq() to take CPU number instead of task Change find_global_dsq() to take a CPU number directly instead of a task pointer. This prepares for callers where the CPU is available but the task is not. No functional changes. v2: Rename tcpu to cpu in find_global_dsq() (Emil Tsalapatis). 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 4c84808299931..35bc5490ee784 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -341,10 +341,9 @@ static bool scx_is_descendant(struct scx_sched *sch, struct scx_sched *ancestor) for ((pos) = scx_next_descendant_pre(NULL, (root)); (pos); \ (pos) = scx_next_descendant_pre((pos), (root))) -static struct scx_dispatch_q *find_global_dsq(struct scx_sched *sch, - struct task_struct *p) +static struct scx_dispatch_q *find_global_dsq(struct scx_sched *sch, s32 cpu) { - return &sch->pnode[cpu_to_node(task_cpu(p))]->global_dsq; + return &sch->pnode[cpu_to_node(cpu)]->global_dsq; } static struct scx_dispatch_q *find_user_dsq(struct scx_sched *sch, u64 dsq_id) @@ -1266,7 +1265,7 @@ static void dispatch_enqueue(struct scx_sched *sch, struct rq *rq, scx_error(sch, "attempting to dispatch to a destroyed dsq"); /* fall back to the global dsq */ raw_spin_unlock(&dsq->lock); - dsq = find_global_dsq(sch, p); + dsq = find_global_dsq(sch, task_cpu(p)); raw_spin_lock(&dsq->lock); } } @@ -1474,7 +1473,7 @@ static void dispatch_dequeue_locked(struct task_struct *p, static struct scx_dispatch_q *find_dsq_for_dispatch(struct scx_sched *sch, struct rq *rq, u64 dsq_id, - struct task_struct *p) + s32 tcpu) { struct scx_dispatch_q *dsq; @@ -1485,20 +1484,19 @@ static struct scx_dispatch_q *find_dsq_for_dispatch(struct scx_sched *sch, s32 cpu = dsq_id & SCX_DSQ_LOCAL_CPU_MASK; if (!ops_cpu_valid(sch, cpu, "in SCX_DSQ_LOCAL_ON dispatch verdict")) - return find_global_dsq(sch, p); + return find_global_dsq(sch, tcpu); return &cpu_rq(cpu)->scx.local_dsq; } if (dsq_id == SCX_DSQ_GLOBAL) - dsq = find_global_dsq(sch, p); + dsq = find_global_dsq(sch, tcpu); else dsq = find_user_dsq(sch, dsq_id); if (unlikely(!dsq)) { - scx_error(sch, "non-existent DSQ 0x%llx for %s[%d]", - dsq_id, p->comm, p->pid); - return find_global_dsq(sch, p); + scx_error(sch, "non-existent DSQ 0x%llx", dsq_id); + return find_global_dsq(sch, tcpu); } return dsq; @@ -1540,7 +1538,7 @@ static void direct_dispatch(struct scx_sched *sch, struct task_struct *p, { struct rq *rq = task_rq(p); struct scx_dispatch_q *dsq = - find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, p); + find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, task_cpu(p)); touch_core_sched_dispatch(rq, p); @@ -1683,7 +1681,7 @@ local: dsq = &rq->scx.local_dsq; goto enqueue; global: - dsq = find_global_dsq(sch, p); + dsq = find_global_dsq(sch, task_cpu(p)); goto enqueue; bypass: dsq = bypass_enq_target_dsq(sch, task_cpu(p)); @@ -2139,7 +2137,7 @@ static struct rq *move_task_between_dsqs(struct scx_sched *sch, dst_rq = container_of(dst_dsq, struct rq, scx.local_dsq); if (src_rq != dst_rq && unlikely(!task_can_run_on_remote_rq(sch, p, dst_rq, true))) { - dst_dsq = find_global_dsq(sch, p); + dst_dsq = find_global_dsq(sch, task_cpu(p)); dst_rq = src_rq; } } else { @@ -2268,7 +2266,7 @@ static void dispatch_to_local_dsq(struct scx_sched *sch, struct rq *rq, if (src_rq != dst_rq && unlikely(!task_can_run_on_remote_rq(sch, p, dst_rq, true))) { - dispatch_enqueue(sch, rq, find_global_dsq(sch, p), p, + dispatch_enqueue(sch, rq, find_global_dsq(sch, task_cpu(p)), p, enq_flags | SCX_ENQ_CLEAR_OPSS); return; } @@ -2406,7 +2404,7 @@ retry: BUG_ON(!(p->scx.flags & SCX_TASK_QUEUED)); - dsq = find_dsq_for_dispatch(sch, this_rq(), dsq_id, p); + dsq = find_dsq_for_dispatch(sch, this_rq(), dsq_id, task_cpu(p)); if (dsq->id == SCX_DSQ_LOCAL) dispatch_to_local_dsq(sch, rq, dsq, p, enq_flags); @@ -2646,7 +2644,7 @@ static void process_ddsp_deferred_locals(struct rq *rq) list_del_init(&p->scx.dsq_list.node); - dsq = find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, p); + dsq = find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, task_cpu(p)); if (!WARN_ON_ONCE(dsq->id != SCX_DSQ_LOCAL)) dispatch_to_local_dsq(sch, rq, dsq, p, p->scx.ddsp_enq_flags); @@ -7409,7 +7407,7 @@ static bool scx_dsq_move(struct bpf_iter_scx_dsq_kern *kit, } /* @p is still on $src_dsq and stable, determine the destination */ - dst_dsq = find_dsq_for_dispatch(sch, this_rq, dsq_id, p); + dst_dsq = find_dsq_for_dispatch(sch, this_rq, dsq_id, task_cpu(p)); /* * Apply vtime and slice updates before moving so that the new time is