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The first patch fixes the tools' restart loop > clobbering an exit that was requested while a restart was pending. > > The rest tighten how cid-addressed operations from sub-schedulers are > handled when the caller lacks the necessary caps. Reenq to another > sched's local DSQs is now denied and counted, and a new event counts > the already-denied kicks. These checks are lockless - transient false > positives from cap rotation are harmless and false negatives can't > happen by visibility. cpuperf control moves behind a new SCX_CAP_PERF > which only the root holds by default, and scx_bpf_cidperf_set() reports > the result synchronously as its check is authoritative under the > target's rq lock. I haven’t found any issues in this series, everything looks good to me. Reviewed-by: Andrea Righi Thanks, -Andrea > > v2: - Kernel-doc comment moved to scx_bpf_cpuperf_set() instead of being > left attached to the factored-out helper (0004, reported by > sashiko). > - The versioned scx_bpf_cidperf_set___v2() interface and the tools > compat wrapper are dropped. The cid-form interface is still under > initial development, so the signature is changed in place to > return s32 (0005). > > v1: https://lore.kernel.org/r/20260724182125.985061-1-tj@kernel.org > > 0001-tools-sched_ext-Don-t-restart-over-a-pending-exit-re.patch > 0002-sched_ext-Gate-local-DSQ-reenq-on-baseline-cid-acces.patch > 0003-sched_ext-Count-kicks-denied-for-lacking-baseline-ci.patch > 0004-sched_ext-Factor-out-scx_cpuperf_set.patch > 0005-sched_ext-Gate-scx_bpf_cidperf_set-behind-a-new-SCX_.patch > > Based on sched_ext/for-7.3 (c509d8107026). > > The patches are also available in the following git branch: > > git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git scx-sub-cap-gates-v2 > > diffstat follows. Thanks. > > kernel/sched/ext/ext.c | 139 +++++++++++++++++++++---------- > kernel/sched/ext/internal.h | 31 ++++++- > tools/sched_ext/include/scx/common.bpf.h | 2 +- > tools/sched_ext/scx_central.c | 2 +- > tools/sched_ext/scx_cpu0.c | 2 +- > tools/sched_ext/scx_flatcg.c | 2 +- > tools/sched_ext/scx_pair.c | 2 +- > tools/sched_ext/scx_qmap.bpf.c | 17 ++-- > tools/sched_ext/scx_qmap.c | 2 +- > tools/sched_ext/scx_sdt.c | 2 +- > tools/sched_ext/scx_simple.c | 2 +- > tools/sched_ext/scx_userland.c | 11 +-- > 12 files changed, 149 insertions(+), 65 deletions(-) > > -- > tejun