bpf: add a test case to test single tp multiple bpf attachment

The bpf sample program syscall_tp is modified to
show attachment of more than bpf programs
for a particular kernel tracepoint.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yonghong Song 2017-10-23 23:53:09 -07:00 committed by David S. Miller
parent e87c6bc385
commit a678be5cc7

View File

@ -23,6 +23,13 @@
* This requires kernel CONFIG_FTRACE_SYSCALLS to be set.
*/
static void usage(const char *cmd)
{
printf("USAGE: %s [-i num_progs] [-h]\n", cmd);
printf(" -i num_progs # number of progs of the test\n");
printf(" -h # help\n");
}
static void verify_map(int map_id)
{
__u32 key = 0;
@ -32,23 +39,30 @@ static void verify_map(int map_id)
fprintf(stderr, "map_lookup failed: %s\n", strerror(errno));
return;
}
if (val == 0)
if (val == 0) {
fprintf(stderr, "failed: map #%d returns value 0\n", map_id);
return;
}
val = 0;
if (bpf_map_update_elem(map_id, &key, &val, BPF_ANY) != 0) {
fprintf(stderr, "map_update failed: %s\n", strerror(errno));
return;
}
}
int main(int argc, char **argv)
static int test(char *filename, int num_progs)
{
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
char filename[256];
int fd;
setrlimit(RLIMIT_MEMLOCK, &r);
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
int i, fd, map0_fds[num_progs], map1_fds[num_progs];
for (i = 0; i < num_progs; i++) {
if (load_bpf_file(filename)) {
fprintf(stderr, "%s", bpf_log_buf);
return 1;
}
printf("prog #%d: map ids %d %d\n", i, map_fd[0], map_fd[1]);
map0_fds[i] = map_fd[0];
map1_fds[i] = map_fd[1];
}
/* current load_bpf_file has perf_event_open default pid = -1
* and cpu = 0, which permits attached bpf execution on
@ -64,8 +78,34 @@ int main(int argc, char **argv)
close(fd);
/* verify the map */
verify_map(map_fd[0]);
verify_map(map_fd[1]);
for (i = 0; i < num_progs; i++) {
verify_map(map0_fds[i]);
verify_map(map1_fds[i]);
}
return 0;
}
int main(int argc, char **argv)
{
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
int opt, num_progs = 1;
char filename[256];
while ((opt = getopt(argc, argv, "i:h")) != -1) {
switch (opt) {
case 'i':
num_progs = atoi(optarg);
break;
case 'h':
default:
usage(argv[0]);
return 0;
}
}
setrlimit(RLIMIT_MEMLOCK, &r);
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
return test(filename, num_progs);
}