This patch series introduces BPF iterators for wakeup_source, enabling BPF programs to efficiently traverse a device's wakeup sources.
Currently, inspecting wakeup sources typically involves reading interfaces like /sys/class/wakeup/* or debugfs. The repeated syscalls to query the sysfs nodes is inefficient, as there can be hundreds of wakeup_sources, and each wakeup source have multiple stats, with one sysfs node per stat. debugfs is unstable and insecure. The iterators utilize pre-existing wakeup_sources_walk_* functions to traverse over the SRCU that backs the list of wakeup_sources. Changes in v4: - Proper init of variables in ws_iter_check_sleep_times() test per bpf-ci - Remove PM patch since it's already part of rebase - v3 link: https://lore.kernel.org/all/[email protected]/ Changes in v3: - Update wakeup_sources_walk_start() to handle an empty list per bpf-ci - Simplify read of a struct's field in BPF program selftest per Andrii - Drop open coded iterators for wakeup_sources - Fix condition from !get_ws_iter_stream to get_ws_iter_stream in selftest - Read event_count instead of wakeup_count in selftest - v2 link: https://lore.kernel.org/all/[email protected]/ Changes in v2: - Guard BPF Makefile with CONFIG_PM_SLEEP to fix build errors - Update copyright from 2025 to 2026 - v1 link: https://lore.kernel.org/all/[email protected]/ Samuel Wu (2): bpf: Add wakeup_source iterator selftests/bpf: Add tests for wakeup_sources kernel/bpf/Makefile | 3 + kernel/bpf/wakeup_source_iter.c | 103 +++++++ tools/testing/selftests/bpf/config | 1 + .../bpf/prog_tests/wakeup_source_iter.c | 281 ++++++++++++++++++ .../selftests/bpf/progs/wakeup_source_iter.c | 60 ++++ 5 files changed, 448 insertions(+) create mode 100644 kernel/bpf/wakeup_source_iter.c create mode 100644 tools/testing/selftests/bpf/prog_tests/wakeup_source_iter.c create mode 100644 tools/testing/selftests/bpf/progs/wakeup_source_iter.c -- 2.53.0.273.g2a3d683680-goog
