From 6e6558a6bc418f1478c5dc8609d03805364e0cb9 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 13 Jun 2025 15:33:10 -1000 Subject: sched_ext, sched/core: Factor out struct scx_task_group More sched_ext fields will be added to struct task_group. In preparation, factor out sched_ext fields into struct scx_task_group to reduce clutter in the common header. No functional changes. Signed-off-by: Tejun Heo --- include/linux/sched/ext.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux/sched') diff --git a/include/linux/sched/ext.h b/include/linux/sched/ext.h index f7545430a548..eda89acdb7ab 100644 --- a/include/linux/sched/ext.h +++ b/include/linux/sched/ext.h @@ -214,4 +214,12 @@ static inline void print_scx_info(const char *log_lvl, struct task_struct *p) {} static inline void scx_softlockup(u32 dur_s) {} #endif /* CONFIG_SCHED_CLASS_EXT */ + +struct scx_task_group { +#ifdef CONFIG_EXT_GROUP_SCHED + u32 flags; /* SCX_TG_* */ + u32 weight; +#endif +}; + #endif /* _LINUX_SCHED_EXT_H */ -- cgit v1.2.3 From ddceadce63d9cb752c2472e220ded05cabaf7971 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 13 Jun 2025 15:34:22 -1000 Subject: sched_ext: Add support for cgroup bandwidth control interface From 077814f57f8acce13f91dc34bbd2b7e4911fbf25 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 13 Jun 2025 15:06:47 -1000 - Add CONFIG_GROUP_SCHED_BANDWIDTH which is selected by both CONFIG_CFS_BANDWIDTH and EXT_GROUP_SCHED. - Put bandwidth control interface files for both cgroup v1 and v2 under CONFIG_GROUP_SCHED_BANDWIDTH. - Update tg_bandwidth() to fetch configuration parameters from fair if CONFIG_CFS_BANDWIDTH, SCX otherwise. - Update tg_set_bandwidth() to update the parameters for both fair and SCX. - Add bandwidth control parameters to struct scx_cgroup_init_args. - Add sched_ext_ops.cgroup_set_bandwidth() which is invoked on bandwidth control parameter updates. - Update scx_qmap and maximal selftest to test the new feature. Signed-off-by: Tejun Heo --- include/linux/sched/ext.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/sched') diff --git a/include/linux/sched/ext.h b/include/linux/sched/ext.h index eda89acdb7ab..8b92842776cb 100644 --- a/include/linux/sched/ext.h +++ b/include/linux/sched/ext.h @@ -219,6 +219,9 @@ struct scx_task_group { #ifdef CONFIG_EXT_GROUP_SCHED u32 flags; /* SCX_TG_* */ u32 weight; + u64 bw_period_us; + u64 bw_quota_us; + u64 bw_burst_us; #endif }; -- cgit v1.2.3 From cb444006a625c60e6d4dd3753863c3c74f96aac3 Mon Sep 17 00:00:00 2001 From: David Dai Date: Tue, 24 Jun 2025 15:49:06 -0700 Subject: sched_ext, rcu: Eject BPF scheduler on RCU CPU stall panic For systems using a sched_ext scheduler and has panic_on_rcu_stall enabled, try kicking out the current scheduler before issuing a panic. While there are numerous reasons for RCU CPU stalls that are not directly attributed to the scheduler, deferring the panic gives sched_ext an opportunity to provide additional debug info when ejecting the current scheduler. Also, handling the event more gracefully allows us to potentially recover the system instead of incurring additional down time. Suggested-by: Tejun Heo Reviewed-by: Paul E. McKenney Signed-off-by: David Dai Signed-off-by: Tejun Heo --- include/linux/sched/ext.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/sched') diff --git a/include/linux/sched/ext.h b/include/linux/sched/ext.h index 8b92842776cb..0cf0915572c9 100644 --- a/include/linux/sched/ext.h +++ b/include/linux/sched/ext.h @@ -206,12 +206,14 @@ struct sched_ext_entity { void sched_ext_free(struct task_struct *p); void print_scx_info(const char *log_lvl, struct task_struct *p); void scx_softlockup(u32 dur_s); +bool scx_rcu_cpu_stall(void); #else /* !CONFIG_SCHED_CLASS_EXT */ static inline void sched_ext_free(struct task_struct *p) {} static inline void print_scx_info(const char *log_lvl, struct task_struct *p) {} static inline void scx_softlockup(u32 dur_s) {} +static inline bool scx_rcu_cpu_stall(void) { return false; } #endif /* CONFIG_SCHED_CLASS_EXT */ -- cgit v1.2.3 From 4ecf83741401c70d4420588ee1f3b1ca04ef58d5 Mon Sep 17 00:00:00 2001 From: Jake Hillion Date: Wed, 25 Jun 2025 18:05:46 +0100 Subject: sched_ext: Drop kfuncs marked for removal in 6.15 sched_ext performed a kfunc renaming pass in 6.13 and kept the old names around for compatibility with old binaries. These were scheduled for cleanup in 6.15 but were missed. Submitting for cleanup in for-next. Removed the kfuncs, their flags, and any references I could find to them in doc comments. Left the entries in include/scx/compat.bpf.h as they're still useful to make new binaries compatible with old kernels. Tested by applying to my kernel. It builds and a modern version of scx_lavd loads fine. Signed-off-by: Jake Hillion Signed-off-by: Tejun Heo --- include/linux/sched/ext.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'include/linux/sched') diff --git a/include/linux/sched/ext.h b/include/linux/sched/ext.h index 0cf0915572c9..7047101dbf58 100644 --- a/include/linux/sched/ext.h +++ b/include/linux/sched/ext.h @@ -164,7 +164,7 @@ struct sched_ext_entity { /* * Runtime budget in nsecs. This is usually set through - * scx_bpf_dispatch() but can also be modified directly by the BPF + * scx_bpf_dsq_insert() but can also be modified directly by the BPF * scheduler. Automatically decreased by SCX as the task executes. On * depletion, a scheduling event is triggered. * @@ -176,10 +176,10 @@ struct sched_ext_entity { /* * Used to order tasks when dispatching to the vtime-ordered priority - * queue of a dsq. This is usually set through scx_bpf_dispatch_vtime() - * but can also be modified directly by the BPF scheduler. Modifying it - * while a task is queued on a dsq may mangle the ordering and is not - * recommended. + * queue of a dsq. This is usually set through + * scx_bpf_dsq_insert_vtime() but can also be modified directly by the + * BPF scheduler. Modifying it while a task is queued on a dsq may + * mangle the ordering and is not recommended. */ u64 dsq_vtime; -- cgit v1.2.3