From 16f0efc3b46352018c297bbdb2c405e7d8a63095 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 23 May 2019 14:47:47 -0700 Subject: tools/bpf: add selftest in test_progs for bpf_send_signal() helper The test covered both nmi and tracepoint perf events. $ ./test_progs ... test_send_signal_tracepoint:PASS:tracepoint 0 nsec ... test_send_signal_common:PASS:tracepoint 0 nsec ... test_send_signal_common:PASS:perf_event 0 nsec ... test_send_signal:OK Acked-by: Andrii Nakryiko Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann --- tools/testing/selftests/bpf/bpf_helpers.h | 1 + .../testing/selftests/bpf/prog_tests/send_signal.c | 198 +++++++++++++++++++++ .../selftests/bpf/progs/test_send_signal_kern.c | 51 ++++++ 3 files changed, 250 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/send_signal.c create mode 100644 tools/testing/selftests/bpf/progs/test_send_signal_kern.c (limited to 'tools') diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index 4b27840b8109..e6d243b7cd74 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -224,6 +224,7 @@ static void *(*bpf_sk_storage_get)(void *map, struct bpf_sock *sk, (void *) BPF_FUNC_sk_storage_get; static int (*bpf_sk_storage_delete)(void *map, struct bpf_sock *sk) = (void *)BPF_FUNC_sk_storage_delete; +static int (*bpf_send_signal)(unsigned sig) = (void *)BPF_FUNC_send_signal; /* llvm builtin functions that eBPF C program may use to * emit BPF_LD_ABS and BPF_LD_IND instructions diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c new file mode 100644 index 000000000000..67cea1686305 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c @@ -0,0 +1,198 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +static volatile int sigusr1_received = 0; + +static void sigusr1_handler(int signum) +{ + sigusr1_received++; +} + +static int test_send_signal_common(struct perf_event_attr *attr, + int prog_type, + const char *test_name) +{ + int err = -1, pmu_fd, prog_fd, info_map_fd, status_map_fd; + const char *file = "./test_send_signal_kern.o"; + struct bpf_object *obj = NULL; + int pipe_c2p[2], pipe_p2c[2]; + __u32 key = 0, duration = 0; + char buf[256]; + pid_t pid; + __u64 val; + + if (CHECK(pipe(pipe_c2p), test_name, + "pipe pipe_c2p error: %s\n", strerror(errno))) + goto no_fork_done; + + if (CHECK(pipe(pipe_p2c), test_name, + "pipe pipe_p2c error: %s\n", strerror(errno))) { + close(pipe_c2p[0]); + close(pipe_c2p[1]); + goto no_fork_done; + } + + pid = fork(); + if (CHECK(pid < 0, test_name, "fork error: %s\n", strerror(errno))) { + close(pipe_c2p[0]); + close(pipe_c2p[1]); + close(pipe_p2c[0]); + close(pipe_p2c[1]); + goto no_fork_done; + } + + if (pid == 0) { + /* install signal handler and notify parent */ + signal(SIGUSR1, sigusr1_handler); + + close(pipe_c2p[0]); /* close read */ + close(pipe_p2c[1]); /* close write */ + + /* notify parent signal handler is installed */ + write(pipe_c2p[1], buf, 1); + + /* make sure parent enabled bpf program to send_signal */ + read(pipe_p2c[0], buf, 1); + + /* wait a little for signal handler */ + sleep(1); + + if (sigusr1_received) + write(pipe_c2p[1], "2", 1); + else + write(pipe_c2p[1], "0", 1); + + /* wait for parent notification and exit */ + read(pipe_p2c[0], buf, 1); + + close(pipe_c2p[1]); + close(pipe_p2c[0]); + exit(0); + } + + close(pipe_c2p[1]); /* close write */ + close(pipe_p2c[0]); /* close read */ + + err = bpf_prog_load(file, prog_type, &obj, &prog_fd); + if (CHECK(err < 0, test_name, "bpf_prog_load error: %s\n", + strerror(errno))) + goto prog_load_failure; + + pmu_fd = syscall(__NR_perf_event_open, attr, pid, -1, + -1 /* group id */, 0 /* flags */); + if (CHECK(pmu_fd < 0, test_name, "perf_event_open error: %s\n", + strerror(errno))) { + err = -1; + goto close_prog; + } + + err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0); + if (CHECK(err < 0, test_name, "ioctl perf_event_ioc_enable error: %s\n", + strerror(errno))) + goto disable_pmu; + + err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); + if (CHECK(err < 0, test_name, "ioctl perf_event_ioc_set_bpf error: %s\n", + strerror(errno))) + goto disable_pmu; + + err = -1; + info_map_fd = bpf_object__find_map_fd_by_name(obj, "info_map"); + if (CHECK(info_map_fd < 0, test_name, "find map %s error\n", "info_map")) + goto disable_pmu; + + status_map_fd = bpf_object__find_map_fd_by_name(obj, "status_map"); + if (CHECK(status_map_fd < 0, test_name, "find map %s error\n", "status_map")) + goto disable_pmu; + + /* wait until child signal handler installed */ + read(pipe_c2p[0], buf, 1); + + /* trigger the bpf send_signal */ + key = 0; + val = (((__u64)(SIGUSR1)) << 32) | pid; + bpf_map_update_elem(info_map_fd, &key, &val, 0); + + /* notify child that bpf program can send_signal now */ + write(pipe_p2c[1], buf, 1); + + /* wait for result */ + err = read(pipe_c2p[0], buf, 1); + if (CHECK(err < 0, test_name, "reading pipe error: %s\n", strerror(errno))) + goto disable_pmu; + if (CHECK(err == 0, test_name, "reading pipe error: size 0\n")) { + err = -1; + goto disable_pmu; + } + + err = CHECK(buf[0] != '2', test_name, "incorrect result\n"); + + /* notify child safe to exit */ + write(pipe_p2c[1], buf, 1); + +disable_pmu: + close(pmu_fd); +close_prog: + bpf_object__close(obj); +prog_load_failure: + close(pipe_c2p[0]); + close(pipe_p2c[1]); + wait(NULL); +no_fork_done: + return err; +} + +static int test_send_signal_tracepoint(void) +{ + const char *id_path = "/sys/kernel/debug/tracing/events/syscalls/sys_enter_nanosleep/id"; + struct perf_event_attr attr = { + .type = PERF_TYPE_TRACEPOINT, + .sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN, + .sample_period = 1, + .wakeup_events = 1, + }; + __u32 duration = 0; + int bytes, efd; + char buf[256]; + + efd = open(id_path, O_RDONLY, 0); + if (CHECK(efd < 0, "tracepoint", + "open syscalls/sys_enter_nanosleep/id failure: %s\n", + strerror(errno))) + return -1; + + bytes = read(efd, buf, sizeof(buf)); + close(efd); + if (CHECK(bytes <= 0 || bytes >= sizeof(buf), "tracepoint", + "read syscalls/sys_enter_nanosleep/id failure: %s\n", + strerror(errno))) + return -1; + + attr.config = strtol(buf, NULL, 0); + + return test_send_signal_common(&attr, BPF_PROG_TYPE_TRACEPOINT, "tracepoint"); +} + +static int test_send_signal_nmi(void) +{ + struct perf_event_attr attr = { + .sample_freq = 50, + .freq = 1, + .type = PERF_TYPE_HARDWARE, + .config = PERF_COUNT_HW_CPU_CYCLES, + }; + + return test_send_signal_common(&attr, BPF_PROG_TYPE_PERF_EVENT, "perf_event"); +} + +void test_send_signal(void) +{ + int ret = 0; + + ret |= test_send_signal_tracepoint(); + ret |= test_send_signal_nmi(); + if (!ret) + printf("test_send_signal:OK\n"); + else + printf("test_send_signal:FAIL\n"); +} diff --git a/tools/testing/selftests/bpf/progs/test_send_signal_kern.c b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c new file mode 100644 index 000000000000..45a1a1a2c345 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook +#include +#include +#include "bpf_helpers.h" + +struct bpf_map_def SEC("maps") info_map = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(__u64), + .max_entries = 1, +}; + +BPF_ANNOTATE_KV_PAIR(info_map, __u32, __u64); + +struct bpf_map_def SEC("maps") status_map = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(__u64), + .max_entries = 1, +}; + +BPF_ANNOTATE_KV_PAIR(status_map, __u32, __u64); + +SEC("send_signal_demo") +int bpf_send_signal_test(void *ctx) +{ + __u64 *info_val, *status_val; + __u32 key = 0, pid, sig; + int ret; + + status_val = bpf_map_lookup_elem(&status_map, &key); + if (!status_val || *status_val != 0) + return 0; + + info_val = bpf_map_lookup_elem(&info_map, &key); + if (!info_val || *info_val == 0) + return 0; + + sig = *info_val >> 32; + pid = *info_val & 0xffffFFFF; + + if ((bpf_get_current_pid_tgid() >> 32) == pid) { + ret = bpf_send_signal(sig); + if (ret == 0) + *status_val = 1; + } + + return 0; +} +char __license[] SEC("license") = "GPL"; -- cgit v1.2.3