kernel/linux.git/Documentation/scheduler, branch v6.19.11

Merge tag 'sched_ext-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

2025-07-31T23:29:46+00:00

Pull sched_ext updates from Tejun Heo: - Add support for cgroup "cpu.max" interface - Code organization cleanup so that ext_idle.c doesn't depend on the source-file-inclusion build method of sched/ - Drop UP paths in accordance with sched core changes - Documentation and other misc changes * tag 'sched_ext-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: sched_ext: Fix scx_bpf_reenqueue_local() reference sched_ext: Drop kfuncs marked for removal in 6.15 sched_ext, rcu: Eject BPF scheduler on RCU CPU stall panic kernel/sched/ext.c: fix typo "occured" -> "occurred" in comments sched_ext: Add support for cgroup bandwidth control interface sched_ext, sched/core: Factor out struct scx_task_group sched_ext: Return NULL in llc_span sched_ext: Always use SMP versions in kernel/sched/ext_idle.h sched_ext: Always use SMP versions in kernel/sched/ext_idle.c sched_ext: Always use SMP versions in kernel/sched/ext.h sched_ext: Always use SMP versions in kernel/sched/ext.c sched_ext: Documentation: Clarify time slice handling in task lifecycle sched_ext: Make scx_locked_rq() inline sched_ext: Make scx_rq_bypassing() inline sched_ext: idle: Make local functions static in ext_idle.c sched_ext: idle: Remove unnecessary ifdef in scx_bpf_cpu_node()

docs/sched: Make the sched-stats documentation consistent

2025-06-09T22:23:58+00:00

pull_task(), the original function to move the task from src_rq to the dst_rq during load balancing was renamed to move_tasks() in commit ddcdf6e7d991 ("sched: Rename load-balancing fields") As a part of commit 163122b7fcfa ("sched/fair: Remove double_lock_balance() from load_balance()"), move_task() was broken down into detach_tasks() and attach_tasks() pair to avoid holding locks of both src_rq and dst_rq at the same time during load balancing. Despite the evolution of pull_task() over the years, the sched-stats documentation remained unchanged. Update the documentation to refer to detach_task() instead of pull_task() which is responsible for removing the task from the src_rq during load balancing. commit 1c055a0f5d3b ("sched: Move sched domain name out of CONFIG_SCHED_DEBUG") moves sched domain name out of CONFIG_SCHED_DEBUG. Update the documentation related to that. Reviewed-by: K Prateek Nayak Suggested-by: Shrikanth Hegde Signed-off-by: Swapnil Sapkal Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20250430062559.1188661-1-swapnil.sapkal@amd.com

sched_deadline, docs: add affinity setting with cgroup2 cpuset controller

2025-06-09T21:01:34+00:00

Setting the cpu affinity mask of a SCHED_DEADLINE process using the cgroup v1 cpuset controller is already detailed. Add similar information for cgroup v2's cpuset controller. Signed-off-by: Shashank Balaji Reviewed-by: Juri Lelli Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20250527-sched-deadline-cpu-affinity-v2-2-b8b40a4feefa@sony.com

sched_deadline, docs: replace rt-app examples with chrt or use config.json

2025-06-09T21:01:34+00:00

rt-app no longer accepts command-line arguments. So, replace rt-app example with chrt and use the JSON format in the other example instead of command- line arguments. Signed-off-by: Shashank Balaji Reviewed-by: Juri Lelli Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20250527-sched-deadline-cpu-affinity-v2-1-b8b40a4feefa@sony.com

sched_ext: Documentation: Clarify time slice handling in task lifecycle

2025-06-09T16:28:33+00:00

It is not always obvious how a task's time slice can be refilled, either explicitly from ops.dispatch() or automatically by the sched_ext core, to skip subsequent ops.enqueue() and ops.dispatch() calls. This typically happens when the task is the only one running on a CPU. To make this behavior easier to understand, update the task lifecycle diagram to explicitly document how time slice handling works in such cases. Signed-off-by: Andrea Righi Signed-off-by: Tejun Heo

Merge tag 'sched_ext-for-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

2025-05-28T04:12:50+00:00

Pull sched_ext updates from Tejun Heo: - More in-kernel idle CPU selection improvements. Expand topology awareness coverage add scx_bpf_select_cpu_and() to allow more flexibility. The idle CPU selection kfuncs can now be called from unlocked contexts too. - A bunch of reorganization changes to lay the foundation for multiple hierarchical scheduler support. This isn't ready yet and the included changes don't make meaningful behavior differences. One notable change is replacing some static_key tests with dynamic tests as the test results may differ depending on the scheduler instance. This isn't expected to cause meaningful performance difference. - Other minor and doc updates. - There were multiple patches in for-6.15-fixes which conflicted with changes in for-6.16. for-6.15-fixes were pulled three times into for-6.16 to resolve the conflicts. * tag 'sched_ext-for-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (49 commits) sched_ext: Call ops.update_idle() after updating builtin idle bits sched_ext, docs: convert mentions of "CFS" to "fair-class scheduler" selftests/sched_ext: Update test enq_select_cpu_fails sched_ext: idle: Consolidate default idle CPU selection kfuncs selftests/sched_ext: Add test for scx_bpf_select_cpu_and() via test_run sched_ext: idle: Allow scx_bpf_select_cpu_and() from unlocked context sched_ext: idle: Validate locking correctness in scx_bpf_select_cpu_and() sched_ext: Make scx_kf_allowed_if_unlocked() available outside ext.c sched_ext, docs: add label sched_ext: Explain the temporary situation around scx_root dereferences sched_ext: Add @sch to SCX_CALL_OP*() sched_ext: Cleanup [__]scx_exit/error*() sched_ext: Add @sch to SCX_CALL_OP*() sched_ext: Clean up scx_root usages Documentation: scheduler: Changed lowercase acronyms to uppercase sched_ext: Avoid NULL scx_root deref in __scx_exit() sched_ext: Add RCU protection to scx_root in DSQ iterator sched_ext: Clean up SCX_EXIT_NONE handling in scx_disable_workfn() sched_ext: Move disable machinery into scx_sched sched_ext: Move event_stats_cpu into scx_sched ...

sched_ext, docs: convert mentions of "CFS" to "fair-class scheduler"

2025-05-22T19:09:10+00:00

Mentions of CFS are stale since the fair-class scheduler is implemented using EEVDF. So, convert such mentions to "fair-class scheduler" to stay algorithm-name agnostic. Signed-off-by: Shashank Balaji Signed-off-by: Tejun Heo

Documentation/scheduler: Fix typo in sched-stats domain field description

2025-05-21T10:20:02+00:00

Fixes a typo in the description of the 23rd field of the scheduling domain statistics, which was missing the word "cpu". Fixes: 7c8cd569ff66 ("docs: Update Schedstat version to 17") Signed-off-by: Madadi Vineeth Reddy Signed-off-by: Jonathan Corbet Message-ID: <20250520100752.39921-1-vineethr@linux.ibm.com>

sched_ext, docs: add label

2025-05-20T20:22:23+00:00

Signed-off-by: Shashank Balaji Signed-off-by: Tejun Heo

Documentation: scheduler: Changed lowercase acronyms to uppercase

2025-05-13T19:19:25+00:00

Everywhere else in this doc, the dispatch queue acronym (DSQ) is uppercase. There were a couple places where the acronym was written in lowercase. I changed them to uppercase to make it homogeneous. Signed-off-by: Jake Rice Signed-off-by: Tejun Heo