kernel/linux.git/tools/sched_ext, branch v6.18.21

tools/sched_ext: fix scx_show_state.py for scx_root change

2026-01-08T09:16:48+00:00

[ Upstream commit f92ff79ba2640fc482bf2bfb5b42e33957f90caf ] Commit 48e126777386 ("sched_ext: Introduce scx_sched") introduced scx_root and removed scx_ops, causing scx_show_state.py to fail when searching for the 'scx_ops' object. [1] Fix by using 'scx_root' instead, with NULL pointer handling. [1] # drgn -s vmlinux ./tools/sched_ext/scx_show_state.py Traceback (most recent call last): File "/root/.venv/bin/drgn", line 8, in sys.exit(_main()) ~~~~~^^ File "/root/.venv/lib64/python3.14/site-packages/drgn/cli.py", line 625, in _main runpy.run_path( ~~~~~~~~~~~~~~^ script_path, init_globals={"prog": prog}, run_name="__main__" ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ) ^ File "", line 287, in run_path File "", line 98, in _run_module_code File "", line 88, in _run_code File "./tools/sched_ext/scx_show_state.py", line 30, in ops = prog['scx_ops'] ~~~~^^^^^^^^^^^ _drgn.ObjectNotFoundError: could not find 'scx_ops' Fixes: 48e126777386 ("sched_ext: Introduce scx_sched") Signed-off-by: Kohei Enju Reviewed-by: Emil Tsalapatis Signed-off-by: Tejun Heo Signed-off-by: Sasha Levin

tools/sched_ext: scx_qmap: Make debug output quieter by default

2025-09-23T19:03:26+00:00

scx_qmap currently outputs verbose debug messages including cgroup operations and CPU online/offline events by default, which can be noisy during normal operation. While the existing -P option controls DSQ dumps and event statistics, there's no way to suppress the other debug messages. Split the debug output controls to make scx_qmap quieter by default. The -P option continues to control DSQ dumps and event statistics (print_dsqs_and_events), while a new -M option controls debug messages like cgroup operations and CPU events (print_msgs). This allows users to run scx_qmap with minimal output and selectively enable debug information as needed. Acked-by: Andrea Righi Signed-off-by: Tejun Heo

sched_ext: Make qmap dump operation non-destructive

2025-09-23T19:03:26+00:00

The qmap dump operation was destructively consuming queue entries while displaying them. As dump can be triggered anytime, this can easily lead to stalls. Add a temporary dump_store queue and modify the dump logic to pop entries, display them, and then restore them back to the original queue. This allows dump operations to be performed without affecting the scheduler's queue state. Note that if racing against new enqueues during dump, ordering can get mixed up, but this is acceptable for debugging purposes. Acked-by: Andrea Righi Signed-off-by: Tejun Heo

tools/sched_ext: Add compat helper for scx_bpf_cpu_curr()

2025-09-04T06:40:45+00:00

Introduce a compatibility helper that allows BPF schedulers to use scx_bpf_cpu_curr() on older kernels. Fixes: 20b158094a1ad ("sched_ext: Introduce scx_bpf_cpu_curr()") Cc: Christian Loehle Signed-off-by: Andrea Righi Signed-off-by: Tejun Heo

sched_ext: Introduce scx_bpf_cpu_curr()

2025-09-03T21:50:42+00:00

Provide scx_bpf_cpu_curr() as a way for scx schedulers to check the curr task of a remote rq without assuming its lock is held. Many scx schedulers make use of scx_bpf_cpu_rq() to check a remote curr (e.g. to see if it should be preempted). This is problematic because scx_bpf_cpu_rq() provides access to all fields of struct rq, most of which aren't safe to use without holding the associated rq lock. Signed-off-by: Christian Loehle Acked-by: Andrea Righi Signed-off-by: Tejun Heo

sched_ext: Introduce scx_bpf_locked_rq()

2025-09-03T21:50:36+00:00

Most fields in scx_bpf_cpu_rq() assume that its rq_lock is held. Furthermore they become meaningless without rq lock, too. Make a safer version of scx_bpf_cpu_rq() that only returns a rq if we hold rq lock of that rq. Also mark the new scx_bpf_locked_rq() as returning NULL as scx_bpf_cpu_rq() should've been too. Signed-off-by: Christian Loehle Acked-by: Andrea Righi Signed-off-by: Tejun Heo

tools/sched_ext: Receive updates from SCX repo

2025-08-11T18:21:57+00:00

Receive tools/sched_ext updates form https://github.com/sched-ext/scx to sync userspace bits: - basic BPF arena allocator abstractions, - additional process flags definitions, - fixed is_migration_disabled() helper, - separate out user_exit_info BPF and user space code. This also fixes the following warning when building the selftests: tools/sched_ext/include/scx/common.bpf.h:550:9: warning: 'likely' macro redefined [-Wmacro-redefined] 550 | #define likely(x) __builtin_expect(!!(x), 1) | ^ Co-developed-by: Cheng-Yang Chou Signed-off-by: Andrea Righi Signed-off-by: Tejun Heo

sched_ext: Add support for cgroup bandwidth control interface

2025-06-21T03:03:51+00:00

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

sched_ext: change the variable name for slice refill event

2025-04-19T03:25:39+00:00

SCX_EV_ENQ_SLICE_DFL gives the impression that the event only occurs when the tasks were enqueued, which seems not accurate. What it actually means is the refilling with defalt slice, and this can occur either when enqueue or pick_task. Let's change the variable to SCX_EV_REFILL_SLICE_DFL. Signed-off-by: Honglei Wang Acked-by: Changwoo Min Acked-by: Andrea Righi Signed-off-by: Tejun Heo

sched_ext: Improve cross-compilation support in Makefile

2025-04-14T16:58:41+00:00

Modify the tools/sched_ext/Makefile to better handle cross-compilation environments by: 1. Fix host tools build directory structure by separating obj/ from output (HOST_BUILD_DIR now points to $(OBJ_DIR)/host/obj) 2. Properly propagate CROSS_COMPILE to libbpf sub-make invocation 3. Add missing $(HOST_BPFOBJ) build rule with proper host toolchain flags (ARCH=, CROSS_COMPILE=, explicit HOSTCC/HOSTLD) 4. Consistently quote $(HOSTCC) in bpftool build rule 5. Change LDFLAGS assignment to += to allow external extensions The changes ensure proper cross-compilation behavior while maintaining backward compatibility with native builds. Host tools are now correctly built with the host toolchain while target binaries use the cross-toolchain. Signed-off-by: yangsonghua Signed-off-by: Tejun Heo