From: Tejun Heo <tj@kernel.org>
To: linux-kernel@vger.kernel.org, sched-ext@lists.linux.dev
Cc: void@manifault.com, arighi@nvidia.com, changwoo@igalia.com,
emil@etsalapatis.com, hannes@cmpxchg.org, mkoutny@suse.com,
cgroups@vger.kernel.org, Tejun Heo <tj@kernel.org>
Subject: [PATCH 24/34] sched_ext: Dispatch from all scx_sched instances
Date: Tue, 24 Feb 2026 19:00:59 -1000 [thread overview]
Message-ID: <20260225050109.1070059-25-tj@kernel.org> (raw)
In-Reply-To: <20260225050109.1070059-1-tj@kernel.org>
The cgroup sub-sched support involves invasive changes to many areas of
sched_ext. The overall scaffolding is now in place and the next step is
implementing sub-sched enable/disable.
To enable partial testing and verification, update balance_one() to
dispatch from all scx_sched instances until it finds a task to run. This
should keep scheduling working when sub-scheds are enabled with tasks on
them. This will be replaced by BPF-driven hierarchical operation.
Signed-off-by: Tejun Heo <tj@kernel.org>
---
kernel/sched/ext.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index 5490bfd77c92..9551bfb0567b 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -2520,7 +2520,7 @@ static bool scx_dispatch_sched(struct scx_sched *sch, struct rq *rq,
static int balance_one(struct rq *rq, struct task_struct *prev)
{
- struct scx_sched *sch = scx_root;
+ struct scx_sched *sch = scx_root, *pos;
s32 cpu = cpu_of(rq);
lockdep_assert_rq_held(rq);
@@ -2564,9 +2564,13 @@ static int balance_one(struct rq *rq, struct task_struct *prev)
if (rq->scx.local_dsq.nr)
goto has_tasks;
- /* dispatch @sch */
- if (scx_dispatch_sched(sch, rq, prev))
- goto has_tasks;
+ /*
+ * TEMPORARY - Dispatch all scheds. This will be replaced by BPF-driven
+ * hierarchical operation.
+ */
+ list_for_each_entry_rcu(pos, &scx_sched_all, all)
+ if (scx_dispatch_sched(pos, rq, prev))
+ goto has_tasks;
/*
* Didn't find another task to run. Keep running @prev unless
--
2.53.0
next prev parent reply other threads:[~2026-02-25 5:01 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-25 5:00 [PATCHSET v2 sched_ext/for-7.1] sched_ext: Implement cgroup sub-scheduler support Tejun Heo
2026-02-25 5:00 ` [PATCH 01/34] sched_ext: Implement cgroup subtree iteration for scx_task_iter Tejun Heo
2026-02-25 5:00 ` [PATCH 02/34] sched_ext: Add @kargs to scx_fork() Tejun Heo
2026-02-25 5:00 ` [PATCH 03/34] sched/core: Swap the order between sched_post_fork() and cgroup_post_fork() Tejun Heo
2026-02-25 5:00 ` [PATCH 04/34] cgroup: Expose some cgroup helpers Tejun Heo
2026-02-25 5:00 ` [PATCH 05/34] sched_ext: Update p->scx.disallow warning in scx_init_task() Tejun Heo
2026-02-25 5:00 ` [PATCH 06/34] sched_ext: Reorganize enable/disable path for multi-scheduler support Tejun Heo
2026-02-25 5:00 ` [PATCH 07/34] sched_ext: Introduce cgroup sub-sched support Tejun Heo
2026-02-26 15:37 ` Andrea Righi
2026-02-27 20:14 ` Tejun Heo
2026-02-26 15:52 ` Andrea Righi
2026-02-27 19:51 ` Tejun Heo
2026-02-27 20:04 ` Tejun Heo
2026-02-25 5:00 ` [PATCH 08/34] sched_ext: Introduce scx_task_sched[_rcu]() Tejun Heo
2026-02-25 5:00 ` [PATCH 09/34] sched_ext: Introduce scx_prog_sched() Tejun Heo
2026-02-25 5:00 ` [PATCH 10/34] sched_ext: Enforce scheduling authority in dispatch and select_cpu operations Tejun Heo
2026-02-25 5:00 ` [PATCH 11/34] sched_ext: Enforce scheduler ownership when updating slice and dsq_vtime Tejun Heo
2026-02-26 15:13 ` Andrea Righi
2026-02-27 22:25 ` Tejun Heo
2026-02-27 23:50 ` Andrea Righi
2026-02-25 5:00 ` [PATCH 12/34] sched_ext: scx_dsq_move() should validate the task belongs to the right scheduler Tejun Heo
2026-02-25 5:00 ` [PATCH 13/34] sched_ext: Refactor task init/exit helpers Tejun Heo
2026-02-27 6:55 ` Andrea Righi
2026-02-27 19:50 ` Tejun Heo
2026-02-25 5:00 ` [PATCH 14/34] sched_ext: Make scx_prio_less() handle multiple schedulers Tejun Heo
2026-02-25 5:00 ` [PATCH 15/34] sched_ext: Move default slice to per-scheduler field Tejun Heo
2026-02-25 5:00 ` [PATCH 16/34] sched_ext: Move aborting flag " Tejun Heo
2026-02-25 5:00 ` [PATCH 17/34] sched_ext: Move bypass_dsq into scx_sched_pcpu Tejun Heo
2026-02-25 5:00 ` [PATCH 18/34] sched_ext: Move bypass state into scx_sched Tejun Heo
2026-02-25 5:00 ` [PATCH 19/34] sched_ext: Prepare bypass mode for hierarchical operation Tejun Heo
2026-02-25 5:00 ` [PATCH 20/34] sched_ext: Factor out scx_dispatch_sched() Tejun Heo
2026-02-25 5:00 ` [PATCH 21/34] sched_ext: When calling ops.dispatch() @prev must be on the same scx_sched Tejun Heo
2026-02-25 5:00 ` [PATCH 22/34] sched_ext: Separate bypass dispatch enabling from bypass depth tracking Tejun Heo
2026-02-25 5:00 ` [PATCH 23/34] sched_ext: Implement hierarchical bypass mode Tejun Heo
2026-02-25 5:00 ` Tejun Heo [this message]
2026-02-25 5:01 ` [PATCH 25/34] sched_ext: Move scx_dsp_ctx and scx_dsp_max_batch into scx_sched Tejun Heo
2026-02-25 5:01 ` [PATCH 26/34] sched_ext: Make watchdog sub-sched aware Tejun Heo
2026-02-25 5:01 ` [PATCH 27/34] sched_ext: Convert scx_dump_state() spinlock to raw spinlock Tejun Heo
2026-02-25 5:01 ` [PATCH 28/34] sched_ext: Support dumping multiple schedulers and add scheduler identification Tejun Heo
2026-02-25 5:01 ` [PATCH 29/34] sched_ext: Implement cgroup sub-sched enabling and disabling Tejun Heo
2026-02-25 5:01 ` [PATCH 30/34] sched_ext: Add scx_sched back pointer to scx_sched_pcpu Tejun Heo
2026-02-25 5:01 ` [PATCH 31/34] sched_ext: Make scx_bpf_reenqueue_local() sub-sched aware Tejun Heo
2026-02-25 5:01 ` [PATCH 32/34] sched_ext: Factor out scx_link_sched() and scx_unlink_sched() Tejun Heo
2026-02-25 5:01 ` [PATCH 33/34] sched_ext: Add rhashtable lookup for sub-schedulers Tejun Heo
2026-02-25 5:01 ` [PATCH 34/34] sched_ext: Add basic building blocks for nested sub-scheduler dispatching Tejun Heo
2026-02-25 5:14 ` [PATCHSET v2 sched_ext/for-7.1] sched_ext: Implement cgroup sub-scheduler support Tejun Heo
-- strict thread matches above, loose matches on Subject: below --
2026-03-04 22:00 [PATCHSET v3 " Tejun Heo
2026-03-04 22:01 ` [PATCH 24/34] sched_ext: Dispatch from all scx_sched instances Tejun Heo
2026-02-25 5:01 [PATCHSET v2 sched_ext/for-7.1] sched_ext: Implement cgroup sub-scheduler support Tejun Heo
2026-02-25 5:01 ` [PATCH 24/34] sched_ext: Dispatch from all scx_sched instances Tejun Heo
2026-01-21 23:11 [PATCHSET v1 sched_ext/for-6.20] sched_ext: Implement cgroup sub-scheduler support Tejun Heo
2026-01-21 23:11 ` [PATCH 24/34] sched_ext: Dispatch from all scx_sched instances Tejun Heo
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