Add testcases to test bpf_send_signal_pid/tgid(). In these new test cases,
the main process triggers the BPF program and the forked process
receives the signals.
Signed-off-by: Puranjay Mohan <puranjay@xxxxxxxxxx>
---
.../selftests/bpf/prog_tests/send_signal.c | 110 +++++++++++++-----
.../bpf/progs/test_send_signal_kern.c | 17 ++-
2 files changed, 95 insertions(+), 32 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c
index 6cc69900b310..a8392dfc69e2 100644
--- a/tools/testing/selftests/bpf/prog_tests/send_signal.c
+++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c
@@ -12,13 +12,15 @@ static void sigusr1_handler(int signum)
}
static void test_send_signal_common(struct perf_event_attr *attr,
- bool signal_thread)
+ bool signal_thread, bool remote)
{
struct test_send_signal_kern *skel;
int pipe_c2p[2], pipe_p2c[2];
int err = -1, pmu_fd = -1;
+ volatile int j = 0;
char buf[256];
pid_t pid;
+ int old_prio;
if (!ASSERT_OK(pipe(pipe_c2p), "pipe_c2p"))
return;
@@ -39,9 +41,6 @@ static void test_send_signal_common(struct perf_event_attr *attr,
}
if (pid == 0) {
- int old_prio;
- volatile int j = 0;
-
/* install signal handler and notify parent */
ASSERT_NEQ(signal(SIGUSR1, sigusr1_handler), SIG_ERR, "signal");
@@ -52,10 +51,12 @@ static void test_send_signal_common(struct perf_event_attr *attr,
* that if an interrupt happens, the underlying task
* is this process.
*/
- errno = 0;
- old_prio = getpriority(PRIO_PROCESS, 0);
- ASSERT_OK(errno, "getpriority");
- ASSERT_OK(setpriority(PRIO_PROCESS, 0, -20), "setpriority");
+ if (!remote) {
+ errno = 0;
+ old_prio = getpriority(PRIO_PROCESS, 0);
+ ASSERT_OK(errno, "getpriority");
+ ASSERT_OK(setpriority(PRIO_PROCESS, 0, -20), "setpriority");
+ }
/* notify parent signal handler is installed */
ASSERT_EQ(write(pipe_c2p[1], buf, 1), 1, "pipe_write");
@@ -66,9 +67,12 @@ static void test_send_signal_common(struct perf_event_attr *attr,
/* wait a little for signal handler */
for (int i = 0; i < 1000000000 && !sigusr1_received; i++) {
j /= i + j + 1;
- if (!attr)
- /* trigger the nanosleep tracepoint program. */
- usleep(1);
+ if (remote)
+ sleep(1);
+ else
+ if (!attr)
+ /* trigger the nanosleep tracepoint program. */
+ usleep(1);
}
buf[0] = sigusr1_received ? '2' : '0';
@@ -79,7 +83,8 @@ static void test_send_signal_common(struct perf_event_attr *attr,
ASSERT_EQ(read(pipe_p2c[0], buf, 1), 1, "pipe_read");
/* restore the old priority */
- ASSERT_OK(setpriority(PRIO_PROCESS, 0, old_prio), "setpriority");
+ if (!remote)
+ ASSERT_OK(setpriority(PRIO_PROCESS, 0, old_prio), "setpriority");
close(pipe_c2p[1]);
close(pipe_p2c[0]);
@@ -93,6 +98,17 @@ static void test_send_signal_common(struct perf_event_attr *attr,
if (!ASSERT_OK_PTR(skel, "skel_open_and_load"))
goto skel_open_load_failure;
+ /* boost with a high priority so we got a higher chance
+ * that if an interrupt happens, the underlying task
+ * is this process.
+ */
+ if (remote) {
+ errno = 0;
+ old_prio = getpriority(PRIO_PROCESS, 0);
+ ASSERT_OK(errno, "getpriority");
+ ASSERT_OK(setpriority(PRIO_PROCESS, 0, -20), "setpriority");
+ }
+
if (!attr) {
err = test_send_signal_kern__attach(skel);
if (!ASSERT_OK(err, "skel_attach")) {
@@ -100,8 +116,12 @@ static void test_send_signal_common(struct perf_event_attr *attr,
goto destroy_skel;
}
} else {
- pmu_fd = syscall(__NR_perf_event_open, attr, pid, -1 /* cpu */,
- -1 /* group id */, 0 /* flags */);
+ if (!remote)
+ pmu_fd = syscall(__NR_perf_event_open, attr, pid, -1 /* cpu */,
+ -1 /* group id */, 0 /* flags */);
+ else
+ pmu_fd = syscall(__NR_perf_event_open, attr, getpid(), -1 /* cpu */,
+ -1 /* group id */, 0 /* flags */);
if (!ASSERT_GE(pmu_fd, 0, "perf_event_open")) {
err = -1;
goto destroy_skel;
@@ -119,11 +139,30 @@ static void test_send_signal_common(struct perf_event_attr *attr,
/* trigger the bpf send_signal */
skel->bss->signal_thread = signal_thread;
skel->bss->sig = SIGUSR1;
- skel->bss->pid = pid;
+ if (!remote) {
+ skel->bss->target_pid = 0;
+ skel->bss->pid = pid;
+ } else {
+ skel->bss->target_pid = pid;
+ skel->bss->pid = getpid();
+ }
/* notify child that bpf program can send_signal now */
ASSERT_EQ(write(pipe_p2c[1], buf, 1), 1, "pipe_write");
+ /* For the remote test, the BPF program is triggered from this
+ * process but the other process/thread is signaled.
+ */
+ if (remote) {
+ if (!attr) {
+ for (int i = 0; i < 10; i++)
+ usleep(1);
+ } else {
+ for (int i = 0; i < 100000000; i++)
+ j /= i + 1;
+ }
+ }
+
/* wait for result */
err = read(pipe_c2p[0], buf, 1);
if (!ASSERT_GE(err, 0, "reading pipe"))
@@ -142,18 +181,21 @@ static void test_send_signal_common(struct perf_event_attr *attr,
close(pmu_fd);
destroy_skel:
test_send_signal_kern__destroy(skel);
+ /* restore the old priority */
+ if (remote)
+ ASSERT_OK(setpriority(PRIO_PROCESS, 0, old_prio), "setpriority");
skel_open_load_failure:
close(pipe_c2p[0]);
close(pipe_p2c[1]);
wait(NULL);
}
-static void test_send_signal_tracepoint(bool signal_thread)
+static void test_send_signal_tracepoint(bool signal_thread, bool remote)
{
- test_send_signal_common(NULL, signal_thread);
+ test_send_signal_common(NULL, signal_thread, remote);
}
-static void test_send_signal_perf(bool signal_thread)
+static void test_send_signal_perf(bool signal_thread, bool remote)
{
struct perf_event_attr attr = {
.freq = 1,
@@ -162,10 +204,10 @@ static void test_send_signal_perf(bool signal_thread)
.config = PERF_COUNT_SW_CPU_CLOCK,
};
- test_send_signal_common(&attr, signal_thread);
+ test_send_signal_common(&attr, signal_thread, remote);
}
-static void test_send_signal_nmi(bool signal_thread)
+static void test_send_signal_nmi(bool signal_thread, bool remote)
{
struct perf_event_attr attr = {
.sample_period = 1,
@@ -191,21 +233,35 @@ static void test_send_signal_nmi(bool signal_thread)
close(pmu_fd);
}
- test_send_signal_common(&attr, signal_thread);
+ test_send_signal_common(&attr, signal_thread, remote);
}
void test_send_signal(void)
{
if (test__start_subtest("send_signal_tracepoint"))
- test_send_signal_tracepoint(false);
+ test_send_signal_tracepoint(false, false);
if (test__start_subtest("send_signal_perf"))
- test_send_signal_perf(false);
+ test_send_signal_perf(false, false);
if (test__start_subtest("send_signal_nmi"))
- test_send_signal_nmi(false);
+ test_send_signal_nmi(false, false);
if (test__start_subtest("send_signal_tracepoint_thread"))
- test_send_signal_tracepoint(true);
+ test_send_signal_tracepoint(true, false);
if (test__start_subtest("send_signal_perf_thread"))
- test_send_signal_perf(true);
+ test_send_signal_perf(true, false);
if (test__start_subtest("send_signal_nmi_thread"))
- test_send_signal_nmi(true);
+ test_send_signal_nmi(true, false);
+
+ /* Signal remote thread and thread group */
+ if (test__start_subtest("send_signal_tracepoint_remote"))
+ test_send_signal_tracepoint(false, true);
+ if (test__start_subtest("send_signal_perf_remote"))
+ test_send_signal_perf(false, true);
+ if (test__start_subtest("send_signal_nmi_remote"))
+ test_send_signal_nmi(false, true);
+ if (test__start_subtest("send_signal_tracepoint_thread_remote"))
+ test_send_signal_tracepoint(true, true);
+ if (test__start_subtest("send_signal_perf_thread_remote"))
+ test_send_signal_perf(true, true);
+ if (test__start_subtest("send_signal_nmi_thread_remote"))
+ test_send_signal_nmi(true, true);
}
diff --git a/tools/testing/selftests/bpf/progs/test_send_signal_kern.c b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c
index 92354cd72044..fd6c055377ae 100644
--- a/tools/testing/selftests/bpf/progs/test_send_signal_kern.c
+++ b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c
@@ -4,7 +4,7 @@
#include <linux/version.h>
#include <bpf/bpf_helpers.h>
-__u32 sig = 0, pid = 0, status = 0, signal_thread = 0;
+__u32 sig = 0, pid = 0, status = 0, signal_thread = 0, target_pid = 0;
static __always_inline int bpf_send_signal_test(void *ctx)
{
@@ -14,10 +14,17 @@ static __always_inline int bpf_send_signal_test(void *ctx)
return 0;
if ((bpf_get_current_pid_tgid() >> 32) == pid) {
- if (signal_thread)
- ret = bpf_send_signal_thread(sig);
- else
- ret = bpf_send_signal(sig);
+ if (signal_thread) {
+ if (target_pid != 0)
+ ret = bpf_send_signal_pid(sig, target_pid);
+ else
+ ret = bpf_send_signal_thread(sig);
+ } else {
+ if (target_pid != 0)
+ ret = bpf_send_signal_tgid(sig, target_pid);
+ else
+ ret = bpf_send_signal(sig);
+ }
if (ret == 0)
status = 1;
}
--
2.40.1
