From: Alexei Starovoitov Date: Sun, 25 Jan 2026 16:20:50 +0000 (-0800) Subject: Merge branch 'selftests-bpf-introduce-execution-context-detection-helpers' X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=59ef78d403806b9d1f8373ea1a2fe63f88ba17da;p=thirdparty%2Fkernel%2Flinux.git Merge branch 'selftests-bpf-introduce-execution-context-detection-helpers' Changwoo Min says: ==================== selftests/bpf: Introduce execution context detection helpers This series introduces four new BPF-native inline helpers -- bpf_in_nmi(), bpf_in_hardirq(), bpf_in_serving_softirq(), and bpf_in_task() -- to allow BPF programs to query the current execution context. Following the feedback on v1, these are implemented in bpf_experimental.h as inline helpers wrapping get_preempt_count(). This approach allows the logic to be JIT-inlined for better performance compared to a kfunc call, while providing the granular context detection (e.g., hardirq vs. softirq) required by subsystems like sched_ext. The series includes a new selftest suite, exe_ctx, which uses bpf_testmod to verify context detection across Task, HardIRQ, and SoftIRQ boundaries via irq_work and tasklets. NMI context testing is omitted as NMIs cannot be triggered deterministically within software-only BPF CI environments. ChangeLog v2 -> v3: - Added exe_ctx to DENYLIST.s390x since new helpers are supported only on x86 and arm64 (patch 2). - Added comments to helpers describing supported architectures (patch 1). ChangeLog v1 -> v2: - Dropped the core kernel kfunc implementations, and implemented context detection as inline BPF helpers in bpf_experimental.h. - Renamed the selftest suite from ctx_kfunc to exe_ctx to reflect the change from kfuncs to helpers. - Updated BPF programs to use the new inline helpers. - Swapped clean-up order between tasklet and irqwork in bpf_testmod to avoid re-scheduling the already-killed tasklet (reported by bot+bpf-ci). ==================== Link: https://patch.msgid.link/20260125115413.117502-1-changwoo@igalia.com Signed-off-by: Alexei Starovoitov --- 59ef78d403806b9d1f8373ea1a2fe63f88ba17da