The test covered both nmi and tracepoint perf events.
$ ./test_send_signal_user
test_send_signal (tracepoint): OK
test_send_signal (perf_event): OK
Signed-off-by: Yonghong Song <y...@fb.com>
---
tools/testing/selftests/bpf/Makefile | 5 +-
tools/testing/selftests/bpf/bpf_helpers.h | 2 +
.../bpf/progs/test_send_signal_kern.c | 50 +++++
.../selftests/bpf/test_send_signal_user.c | 186 ++++++++++++++++++
4 files changed, 241 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_send_signal_kern.c
create mode 100644 tools/testing/selftests/bpf/test_send_signal_user.c
diff --git a/tools/testing/selftests/bpf/Makefile
b/tools/testing/selftests/bpf/Makefile
index 66f2dca1dee1..c3aa33dfae18 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -23,7 +23,8 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps
test_lru_map test_lpm_map test
test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
test_sock test_btf test_sockmap test_lirc_mode2_user get_cgroup_id_user
\
test_socket_cookie test_cgroup_storage test_select_reuseport
test_section_names \
- test_netcnt test_tcpnotify_user test_sock_fields test_sysctl
+ test_netcnt test_tcpnotify_user test_sock_fields test_sysctl \
+ test_send_signal_user
BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
TEST_GEN_FILES = $(BPF_OBJ_FILES)
@@ -124,7 +125,7 @@ endif
CLANG_SYS_INCLUDES := $(shell $(CLANG) -v -E - </dev/null 2>&1 \
| sed -n '/<...> search starts here:/,/End of search list./{ s|
\(/.*\)|-idirafter \1|p }')
-CLANG_FLAGS = -I. -I./include/uapi -I../../../include/uapi \
+CLANG_FLAGS = -I. -I./include/uapi -I../../../include/uapi -I../../../include \
$(CLANG_SYS_INCLUDES) \
-Wno-compare-distinct-pointer-types
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h
b/tools/testing/selftests/bpf/bpf_helpers.h
index 6e80b66d7fb1..4517bca4f9ed 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -216,6 +216,8 @@ 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 pid, 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/progs/test_send_signal_kern.c
b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c
new file mode 100644
index 000000000000..b81dbbf60b3d
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+#include <linux/bpf.h>
+#include <linux/bpf_perf_event.h>
+#include <linux/version.h>
+#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;
+
+ ret = bpf_send_signal(pid, sig);
+ if (ret == 0)
+ *status_val = 1;
+
+ return 0;
+}
+char __license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_send_signal_user.c
b/tools/testing/selftests/bpf/test_send_signal_user.c
new file mode 100644
index 000000000000..38898c575bd2
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_send_signal_user.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#include <syscall.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <linux/perf_event.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include "bpf_rlimit.h"
+
+static volatile int signal_received = 0;
+
+static void sigusr1_handler(int signum)
+{
+ signal_received++;
+}
+
+static void test_common(struct perf_event_attr *attr, int prog_type,
+ const char *test_name, int trace_pid, int cpu)
+{
+ int 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];
+ char buf[256];
+ int err = 0;
+ u32 key = 0;
+ pid_t pid;
+ u64 val;
+
+ if (pipe(pipe_c2p) < 0) {
+ fprintf(stderr, "Creating pipe c2p error\n");
+ return;
+ }
+ if (pipe(pipe_p2c) < 0) {
+ fprintf(stderr, "Creating pipe p2c error\n");
+ return;
+ }
+
+ pid = fork();
+ 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 sense parent enabled bpf program to send_signal */
+ read(pipe_p2c[0], buf, 1);
+
+ /* wait a little for signal handler */
+ sleep(1);
+
+ if (signal_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);
+ 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 (err) {
+ printf("test_send_signal:bpf_prog_load errno %d\n", errno);
+ goto close_prog;
+ }
+
+ pmu_fd = syscall(__NR_perf_event_open, attr, trace_pid, cpu,
+ -1 /* group id */, 0 /* flags */);
+ if (pmu_fd < 0)
+ goto close_prog;
+
+ err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
+ if (err)
+ goto disable_pmu;
+
+ err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd);
+ if (err)
+ goto disable_pmu;
+
+ info_map_fd = bpf_object__find_map_fd_by_name(obj, "info_map");
+ if (info_map_fd < 0)
+ goto disable_pmu;
+
+ status_map_fd = bpf_object__find_map_fd_by_name(obj, "status_map");
+ if (status_map_fd < 0)
+ 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 */
+ read(pipe_c2p[0], buf, 1);
+
+ if (buf[0] == '2')
+ printf("test_send_signal (%s): OK\n", test_name);
+ else
+ printf("test_send_signal (%s): FAIL\n", test_name);
+
+ /* notify child safe to exit */
+ write(pipe_p2c[1], buf, 1);
+
+ goto close_prog_noerr;
+
+close_prog:
+disable_pmu:
+ printf("test_send_signal (%s) :FAIL\n", test_name);
+close_prog_noerr:
+ bpf_object__close(obj);
+
+ wait(NULL);
+}
+
+static void test_tracepoint(void)
+{
+ struct perf_event_attr attr = {
+ .type = PERF_TYPE_TRACEPOINT,
+ .sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN,
+ .sample_period = 1,
+ .wakeup_events = 1,
+ };
+ int bytes, efd;
+ char buf[256];
+
+ snprintf(buf, sizeof(buf),
+
"/sys/kernel/debug/tracing/events/syscalls/sys_enter_nanosleep/id");
+ efd = open(buf, O_RDONLY, 0);
+ if (efd < 0) {
+ printf("test_send_signal:bpf_prog_load errno %d\n", errno);
+ return;
+ }
+
+ bytes = read(efd, buf, sizeof(buf));
+ close(efd);
+ if (bytes <= 0 || bytes >= sizeof(buf))
+ return;
+
+ attr.config = strtol(buf, NULL, 0);
+
+ test_common(&attr, BPF_PROG_TYPE_TRACEPOINT, "tracepoint", -1, 0);
+}
+
+static void test_nmi_perf_event(void)
+{
+ struct perf_event_attr attr = {
+ .sample_freq = 50,
+ .freq = 1,
+ .type = PERF_TYPE_HARDWARE,
+ .config = PERF_COUNT_HW_CPU_CYCLES,
+ };
+
+ test_common(&attr, BPF_PROG_TYPE_PERF_EVENT, "perf_event", -1, 0);
+}
+
+int main(void)
+{
+ test_tracepoint();
+ test_nmi_perf_event();
+ return 0;
+}
--
2.17.1
