Sets up the framework to test wakeup_sources iterators using BPF, and adds a few basic tests.
Adds several helper functions that for grabbing and releasing a wakelock, abstracting out key functions to setup a framework for testing wakeup_sources.
Additionally, adds 3 tests: 1. check_active_count: Checks that stats related to active_count are properly set after several lock/unlock cycles 2. check_sleep_times: Checks that time accounting related to sleep are properly calculated 3. check_no_infinite_reads: Checks that the iterator traversal returns NULL at the end
Signed-off-by: Samuel Wu wusamuel@google.com --- tools/testing/selftests/bpf/config | 1 + .../bpf/prog_tests/wakeup_source_iter.c | 281 ++++++++++++++++++ .../selftests/bpf/progs/wakeup_source_iter.c | 70 +++++ 3 files changed, 352 insertions(+) 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
diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 558839e3c185..c12c5e04b81f 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -111,6 +111,7 @@ CONFIG_IP6_NF_IPTABLES=y CONFIG_IP6_NF_FILTER=y CONFIG_NF_NAT=y CONFIG_PACKET=y +CONFIG_PM_WAKELOCKS=y CONFIG_RC_CORE=y CONFIG_SAMPLES=y CONFIG_SAMPLE_LIVEPATCH=m diff --git a/tools/testing/selftests/bpf/prog_tests/wakeup_source_iter.c b/tools/testing/selftests/bpf/prog_tests/wakeup_source_iter.c new file mode 100644 index 000000000000..31729f11585e --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/wakeup_source_iter.c @@ -0,0 +1,281 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Google LLC */ + +#include <test_progs.h> +#include <bpf/libbpf.h> +#include "wakeup_source_iter.skel.h" + +#include <fcntl.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + + +/* Sleep for 10ms to ensure active time is > 0 after converting ns to ms*/ +#define TEST_SLEEP_US 10000 +#define TEST_SLEEP_MS (TEST_SLEEP_US / 1000) +#define WAKEUP_SOURCE_NAME_LEN 32 + +static const char test_ws_name[] = "bpf_selftest_ws"; +static bool test_ws_created; + +/* + * Creates a new wakeup source by writing to /sys/power/wake_lock. + * This lock persists until explicitly unlocked. + */ +static int lock_ws(const char *name) +{ + int fd; + ssize_t bytes; + + fd = open("/sys/power/wake_lock", O_WRONLY); + if (!ASSERT_OK_FD(fd, "open /sys/power/wake_lock")) + return -1; + + bytes = write(fd, name, strlen(name)); + close(fd); + if (!ASSERT_EQ(bytes, strlen(name), "write to wake_lock")) + return -1; + + return 0; +} + +/* + * Destroys the ws by writing the same name to /sys/power/wake_unlock. + */ +static void unlock_ws(const char *name) +{ + int fd; + + fd = open("/sys/power/wake_unlock", O_WRONLY); + if (!ASSERT_OK_FD(fd, "open /sys/power/wake_unlock")) + goto cleanup; + + write(fd, name, strlen(name)); + +cleanup: + if (fd) + close(fd); +} + +/* + * Setups for testing ws iterators. Will run once prior to suite of tests. + */ +static int setup_test_ws(void) +{ + if (lock_ws(test_ws_name)) + return -1; + test_ws_created = true; + + return 0; +} + +/* + * Tears down and cleanups testing ws iterators. WIll run once after the suite + * of tests. + */ +static void teardown_test_ws(void) +{ + if (!test_ws_created) + return; + unlock_ws(test_ws_name); + test_ws_created = false; +} + +struct WakeupSourceInfo { + char name[WAKEUP_SOURCE_NAME_LEN]; + unsigned long active_count; + long active_time_ms; + unsigned long event_count; + unsigned long expire_count; + long last_change_ms; + long max_time_ms; + long prevent_sleep_time_ms; + long total_time_ms; + unsigned long wakeup_count; +}; + +/* + * Reads and parses one wakeup_source record from the iterator file. + * A record is a single space-delimited line. + * Returns true on success, false on EOF. Asserts internally on errors. + */ +static bool read_ws_info(FILE *iter_file, struct WakeupSourceInfo *ws_info, + char **line) +{ + size_t linesize; + int items; + + if (getline(line, &linesize, iter_file) == -1) + return false; + + (*line)[strcspn(*line, "\n")] = 0; + + items = sscanf(*line, "%s %lu %ld %lu %lu %ld %ld %ld %ld %lu", + ws_info->name, &ws_info->active_count, + &ws_info->active_time_ms, &ws_info->event_count, + &ws_info->expire_count, &ws_info->last_change_ms, + &ws_info->max_time_ms, &ws_info->prevent_sleep_time_ms, + &ws_info->total_time_ms, &ws_info->wakeup_count); + + if (!ASSERT_EQ(items, 10, "read wakeup source info")) + return false; + + if (!ASSERT_LT(strlen(ws_info->name), WAKEUP_SOURCE_NAME_LEN, + "name length")) + return false; + + return true; +} + +static int get_ws_iter_stream(struct wakeup_source_iter *skel, int *iter_fd, + FILE **iter_file) +{ + *iter_fd = bpf_iter_create( + bpf_link__fd(skel->links.wakeup_source_collector)); + if (!ASSERT_OK_FD(*iter_fd, "iter_create")) + return -1; + + *iter_file = fdopen(*iter_fd, "r"); + if (!ASSERT_OK_PTR(*iter_file, "fdopen")) + return -1; + + return 0; +} + +static void subtest_ws_iter_check_active_count(struct wakeup_source_iter *skel) +{ + static const char subtest_ws_name[] = "bpf_selftest_ws_active_count"; + const int lock_unlock_cycles = 5; + struct WakeupSourceInfo ws_info; + char *line = NULL; + bool found_ws = false; + FILE *iter_file = NULL; + int iter_fd = -1; + int i; + + for (i = 0; i < lock_unlock_cycles; i++) { + if (!ASSERT_OK(lock_ws(subtest_ws_name), "lock_ws")) + goto cleanup; + unlock_ws(subtest_ws_name); + } + + if (!get_ws_iter_stream(skel, &iter_fd, &iter_file)) + goto cleanup; + + while (read_ws_info(iter_file, &ws_info, &line)) { + if (strcmp(ws_info.name, subtest_ws_name) == 0) { + found_ws = true; + ASSERT_EQ(ws_info.active_count, lock_unlock_cycles, + "active_count check"); + ASSERT_EQ(ws_info.wakeup_count, lock_unlock_cycles, + "wakeup_count check"); + break; + } + } + + ASSERT_TRUE(found_ws, "found active_count test ws"); + + free(line); +cleanup: + if (iter_file) + fclose(iter_file); + else if (iter_fd >= 0) + close(iter_fd); +} + +static void subtest_ws_iter_check_sleep_times(struct wakeup_source_iter *skel) +{ + bool found_test_ws = false; + struct WakeupSourceInfo ws_info; + char *line = NULL; + FILE *iter_file; + int iter_fd; + + if (!get_ws_iter_stream(skel, &iter_fd, &iter_file)) + goto cleanup; + + while (read_ws_info(iter_file, &ws_info, &line)) { + if (strcmp(ws_info.name, test_ws_name) == 0) { + found_test_ws = true; + ASSERT_GT(ws_info.last_change_ms, 0, + "Expected non-zero last change"); + ASSERT_GE(ws_info.active_time_ms, TEST_SLEEP_MS, + "Expected active time >= TEST_SLEEP_MS"); + ASSERT_GE(ws_info.max_time_ms, TEST_SLEEP_MS, + "Expected max time >= TEST_SLEEP_MS"); + ASSERT_GE(ws_info.total_time_ms, TEST_SLEEP_MS, + "Expected total time >= TEST_SLEEP_MS"); + break; + } + } + + ASSERT_TRUE(found_test_ws, "found_test_ws"); + + free(line); +cleanup: + if (iter_file) + fclose(iter_file); + else if (iter_fd >= 0) + close(iter_fd); +} + +static void subtest_ws_iter_check_no_infinite_reads( + struct wakeup_source_iter *skel) +{ + int iter_fd; + char buf[256]; + + iter_fd = bpf_iter_create(bpf_link__fd(skel->links.wakeup_source_collector)); + if (!ASSERT_OK_FD(iter_fd, "iter_create")) + return; + + while (read(iter_fd, buf, sizeof(buf)) > 0) + ; + + /* Final read should return 0 */ + ASSERT_EQ(read(iter_fd, buf, sizeof(buf)), 0, "read"); + + close(iter_fd); +} + +void test_wakeup_source_iter(void) +{ + struct wakeup_source_iter *skel = NULL; + + if (geteuid() != 0) { + fprintf(stderr, + "Skipping wakeup_source_iter test, requires root\n"); + test__skip(); + return; + } + + skel = wakeup_source_iter__open_and_load(); + if (!ASSERT_OK_PTR(skel, "wakeup_source_iter__open_and_load")) + return; + + if (!ASSERT_OK(setup_test_ws(), "setup_test_ws")) + goto destroy; + + if (!ASSERT_OK(wakeup_source_iter__attach(skel), "skel_attach")) + goto destroy; + + /* + * Sleep on O(ms) to ensure that time stats' resolution isn't lost when + * converting from ns to ms + */ + usleep(TEST_SLEEP_US); + + if (test__start_subtest("active_count")) + subtest_ws_iter_check_active_count(skel); + if (test__start_subtest("sleep_times")) + subtest_ws_iter_check_sleep_times(skel); + if (test__start_subtest("no_infinite_reads")) + subtest_ws_iter_check_no_infinite_reads(skel); + +destroy: + teardown_test_ws(); + wakeup_source_iter__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/wakeup_source_iter.c b/tools/testing/selftests/bpf/progs/wakeup_source_iter.c new file mode 100644 index 000000000000..9a377fd28f4e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/wakeup_source_iter.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Google LLC */ +#include <vmlinux.h> +#include <bpf/bpf_core_read.h> +#include <bpf/bpf_helpers.h> + +#define NSEC_PER_MS 1000000UL +#define WAKEUP_SOURCE_NAME_LEN 32 + +char _license[] SEC("license") = "GPL"; + +SEC("iter/wakeup_source") +int wakeup_source_collector(struct bpf_iter__wakeup_source *ctx) +{ + const struct wakeup_source *ws = ctx->wakeup_source; + struct seq_file *seq = ctx->meta->seq; + char name[WAKEUP_SOURCE_NAME_LEN] = {'\0'}; + const char *pname; + bool active, autosleep_enable; + u64 active_count, event_count, expire_count, wakeup_count; + s64 active_time, curr_time, last_change_time, max_time, + prevent_sleep_time, start_prevent_time, total_time; + + if (!ws) + return 0; + + active = BPF_CORE_READ_BITFIELD_PROBED(ws, active); + autosleep_enable = BPF_CORE_READ_BITFIELD_PROBED(ws, autosleep_enabled); + if (bpf_core_read(&pname, sizeof(pname), &ws->name) || + bpf_probe_read_kernel_str(name, sizeof(name), pname) < 0 || + bpf_core_read(&active_count, sizeof(active_count), &ws->active_count) || + bpf_core_read(&event_count, sizeof(event_count), &ws->event_count) || + bpf_core_read(&expire_count, sizeof(expire_count), &ws->expire_count) || + bpf_core_read(&last_change_time, sizeof(last_change_time), &ws->last_time) || + bpf_core_read(&max_time, sizeof(max_time), &ws->max_time) || + bpf_core_read( + &prevent_sleep_time, sizeof(prevent_sleep_time), &ws->prevent_sleep_time) || + bpf_core_read( + &start_prevent_time, sizeof(start_prevent_time), &ws->start_prevent_time) || + bpf_core_read(&total_time, sizeof(total_time), &ws->total_time) || + bpf_core_read(&wakeup_count, sizeof(wakeup_count), &ws->wakeup_count)) + return 0; + + + curr_time = bpf_ktime_get_ns(); + active_time = 0; + if (active) { + active_time = curr_time - last_change_time; + total_time += active_time; + if (active_time > max_time) + max_time = active_time; + if (autosleep_enable) + prevent_sleep_time += curr_time - start_prevent_time; + + } + + BPF_SEQ_PRINTF(seq, + "%s %lu %ld %lu %lu %ld %ld %ld %ld %lu\n", + name, + active_count, + active_time / NSEC_PER_MS, + event_count, + expire_count, + last_change_time / NSEC_PER_MS, + max_time / NSEC_PER_MS, + prevent_sleep_time / NSEC_PER_MS, + total_time / NSEC_PER_MS, + wakeup_count); + return 0; +}