linux/kernel/sched
Linus Torvalds 5b33fc6492 sched_ext: Changes for v7.2
This depends on the BPF arena work in bpf-next and should be pulled after
 it. for-7.1-fixes was merged in a few times to avoid conflicts with the
 feature changes.
 
 - Most of this continues the in-development sub-scheduler support, which
   lets a root BPF scheduler delegate to nested sub-schedulers. The
   dispatch-path building blocks landed in 7.1. A follow-up patchset in
   development will complete enqueue-path support for hierarchical
   scheduling. This cycle adds most of that infrastructure:
 
   - Topological CPU IDs (cids): a dense, topology-ordered CPU numbering
     where the CPUs of a core, LLC, or NUMA node form contiguous ranges,
     so a topology unit becomes a (start, length) slice. Raw CPU numbers
     are sparse and don't track topological closeness, which makes them
     clumsy for sharding work across sub-schedulers and awkward in BPF.
 
   - cmask: bitmaps windowed over a slice of cid space, so a sub-scheduler
     can track, for example, the idle cids of its shard without a full
     NR_CPUS cpumask.
 
   - A struct_ops variant that cid-form sub-schedulers register with,
     along with the cid-form kfuncs they call.
 
   - BPF arena integration, which sub-scheduler support is built on. The
     bpf-next additions let the kernel read and write the BPF scheduler's
     arena directly, turning it into a real kernel/BPF shared-memory
     channel. Shared state like the per-CPU cmask now lives there.
 
   - scx_qmap is reworked to exercise the new arena and cid interfaces.
 
 - Exit-dump improvements: dump the faulting CPU first, expose the exit
   CPU to BPF and userspace, and normalize the dump header.
 
 - Misc kfuncs and cleanups: a task-ID lookup kfunc, __printf checking on
   the error and dump formatters, header reorganization, and assorted
   fixes.
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Merge tag 'sched_ext-for-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

Pull sched_ext updates from Tejun Heo:
 "Most of this continues the in-development sub-scheduler support, which
  lets a root BPF scheduler delegate to nested sub-schedulers. The
  dispatch-path building blocks landed in 7.1. A follow-up patchset in
  development will complete enqueue-path support for hierarchical
  scheduling. This cycle adds most of that infrastructure:

   - Topological CPU IDs (cids): a dense, topology-ordered CPU numbering
     where the CPUs of a core, LLC, or NUMA node form contiguous ranges,
     so a topology unit becomes a (start, length) slice. Raw CPU numbers
     are sparse and don't track topological closeness, which makes them
     clumsy for sharding work across sub-schedulers and awkward in BPF.

   - cmask: bitmaps windowed over a slice of cid space, so a
     sub-scheduler can track, for example, the idle cids of its shard
     without a full NR_CPUS cpumask.

   - A struct_ops variant that cid-form sub-schedulers register with,
     along with the cid-form kfuncs they call.

   - BPF arena integration, which sub-scheduler support is built on. The
     bpf-next additions let the kernel read and write the BPF
     scheduler's arena directly, turning it into a real kernel/BPF
     shared-memory channel. Shared state like the per-CPU cmask now
     lives there.

   - scx_qmap is reworked to exercise the new arena and cid interfaces.

  Additionally:

   - Exit-dump improvements: dump the faulting CPU first, expose the
     exit CPU to BPF and userspace, and normalize the dump header.

   - Misc kfuncs and cleanups: a task-ID lookup kfunc, __printf checking
     on the error and dump formatters, header reorganization, and
     assorted fixes"

* tag 'sched_ext-for-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (59 commits)
  sched_ext: Add scx_arena_to_kaddr() / scx_kaddr_to_arena()
  sched_ext: Make scx_bpf_kick_cid() return s32
  sched_ext: Add scx_cmask_test() and scx_cmask_for_each_cid()
  tools/sched_ext: Order single-cid cmask helpers as (cid, mask)
  sched_ext: Order single-cid cmask helpers as (cid, mask)
  selftests/sched_ext: Fix dsq_move_to_local check
  sched_ext: Guard BPF arena helper calls to fix 32-bit build
  sched_ext: idle: Fix errno loss in scx_idle_init()
  sched_ext: Convert ops.set_cmask() to arena-resident cmask
  sched_ext: Sub-allocator over kernel-claimed BPF arena pages
  sched_ext: Require an arena for cid-form schedulers
  sched_ext: Add cmask mask ops
  sched_ext: Track bits[] storage size in struct scx_cmask
  sched_ext: Rename scx_cmask.nr_bits to nr_cids
  tools/sched_ext: scx_qmap: Fix qa arena placement
  sched_ext: Mark !CONFIG_EXT_SUB_SCHED dummy stubs static inline
  sched_ext: Replace tryget_task_struct() with get_task_struct()
  sched_ext: Add scx_task_iter_relock() and use it in scx_root_enable_workfn()
  sched_ext: Fix ops_cid layout assert
  sched_ext: Use offsetofend on both sides of the ops_cid layout assert
  ...
2026-06-17 12:10:11 +01:00
..
autogroup.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
autogroup.h sched: Clean up and standardize #if/#else/#endif markers in sched/autogroup.[ch] 2025-06-13 08:47:14 +02:00
build_policy.c sched_ext: Sub-allocator over kernel-claimed BPF arena pages 2026-05-25 09:44:07 -10:00
build_utility.c sched/smp: Make SMP unconditional 2025-06-13 08:47:18 +02:00
clock.c sched/clock: Avoid false sharing for sched_clock_irqtime 2026-02-03 12:04:19 +01:00
completion.c sched: Make clangd usable 2025-06-11 11:20:53 +02:00
core_sched.c sched: Unify SMT active check via sched_smt_active() 2026-05-19 12:17:37 +02:00
core.c Scheduler updates for v7.2: 2026-06-15 14:50:18 +05:30
cpuacct.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cpudeadline.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cpudeadline.h sched/deadline: only set free_cpus for online runqueues 2025-10-16 11:13:49 +02:00
cpufreq_schedutil.c cpufreq: Pass the policy to cpufreq_driver->adjust_perf() 2026-04-02 11:30:24 -05:00
cpufreq.c sched: Make clangd usable 2025-06-11 11:20:53 +02:00
cpupri.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cpupri.h sched/smp: Make SMP unconditional 2025-06-13 08:47:18 +02:00
cputime.c Scheduler updates for v7.2: 2026-06-15 14:50:18 +05:30
deadline.c Scheduler updates for v7.2: 2026-06-15 14:50:18 +05:30
debug.c sched/fair: Remove task_group->se pointer array 2026-06-02 12:26:11 +02:00
ext_arena.c sched_ext: Guard BPF arena helper calls to fix 32-bit build 2026-05-31 08:01:47 -10:00
ext_arena.h sched_ext: Sub-allocator over kernel-claimed BPF arena pages 2026-05-25 09:44:07 -10:00
ext_cid.c sched_ext: Order single-cid cmask helpers as (cid, mask) 2026-06-03 15:46:56 -10:00
ext_cid.h sched_ext: Add scx_cmask_test() and scx_cmask_for_each_cid() 2026-06-03 15:46:56 -10:00
ext_idle.c sched_ext: Changes for v7.2 2026-06-17 12:10:11 +01:00
ext_idle.h sched_ext: Deny SCX kfuncs to non-SCX struct_ops programs 2026-04-20 07:57:29 -10:00
ext_internal.h sched_ext: Add scx_arena_to_kaddr() / scx_kaddr_to_arena() 2026-06-03 23:57:03 -10:00
ext_types.h sched_ext: Track bits[] storage size in struct scx_cmask 2026-05-20 21:14:39 -10:00
ext.c sched_ext: Changes for v7.2 2026-06-17 12:10:11 +01:00
ext.h sched_ext: Add @kargs to scx_fork() 2026-03-06 07:58:02 -10:00
fair.c sched/fair: Fix newidle vs core-sched 2026-06-11 13:41:23 +02:00
features.h sched/rt: Have RT_PUSH_IPI be default off for non PREEMPT_RT 2026-05-19 12:17:39 +02:00
idle.c Scheduler updates for v7.2: 2026-06-15 14:50:18 +05:30
isolation.c cgroup/cpuset: Call housekeeping_update() without holding cpus_read_lock 2026-02-23 10:46:49 -10:00
loadavg.c Merge branch 'tip/sched/urgent' 2025-07-14 17:16:28 +02:00
Makefile sched: Enable context analysis for core.c and fair.c 2026-01-05 16:43:36 +01:00
membarrier.c Locking updates for v7.2: 2026-06-15 14:21:14 +05:30
pelt.c treewide: Update email address 2026-01-11 06:09:11 -10:00
pelt.h sched/fair: Switch to task based throttle model 2025-09-03 10:03:14 +02:00
psi.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rq-offsets.c sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
rt.c sched: Rework prev_balance() to avoid stale prev references 2026-06-02 12:26:06 +02:00
sched-pelt.h sched: Make clangd usable 2025-06-11 11:20:53 +02:00
sched.h sched/fair: Allocate cfs_tg_state with percpu allocator 2026-06-02 12:26:11 +02:00
smp.h sched: Make clangd usable 2025-06-11 11:20:53 +02:00
stats.c sched/smp: Use the SMP version of schedstats 2025-06-13 08:47:21 +02:00
stats.h sched/fair: Co-locate cfs_rq and sched_entity in cfs_tg_state 2026-06-02 12:26:10 +02:00
stop_task.c sched: Rework prev_balance() to avoid stale prev references 2026-06-02 12:26:06 +02:00
swait.c sched: Make clangd usable 2025-06-11 11:20:53 +02:00
syscalls.c Linux 7.0-rc4 2026-03-17 07:14:42 +01:00
topology.c sched/topology: Provide arch_llc_mask for cache aware scheduling 2026-05-29 12:43:15 +02:00
wait_bit.c sched: Make clangd usable 2025-06-11 11:20:53 +02:00
wait.c ARM: 2025-07-30 17:14:01 -07:00