diff options
Diffstat (limited to 'samples/bpf/trace_event_user.c')
| -rw-r--r-- | samples/bpf/trace_event_user.c | 139 |
1 files changed, 93 insertions, 46 deletions
diff --git a/samples/bpf/trace_event_user.c b/samples/bpf/trace_event_user.c index 356171bc392b..b6cd358d0418 100644 --- a/samples/bpf/trace_event_user.c +++ b/samples/bpf/trace_event_user.c @@ -6,22 +6,25 @@ #include <stdlib.h> #include <stdbool.h> #include <string.h> -#include <fcntl.h> -#include <poll.h> -#include <sys/ioctl.h> #include <linux/perf_event.h> #include <linux/bpf.h> #include <signal.h> -#include <assert.h> #include <errno.h> #include <sys/resource.h> +#include <bpf/bpf.h> #include <bpf/libbpf.h> -#include "bpf_load.h" #include "perf-sys.h" #include "trace_helpers.h" +#define __must_check +#include <linux/err.h> + #define SAMPLE_FREQ 50 +static int pid; +/* counts, stackmap */ +static int map_fd[2]; +struct bpf_program *prog; static bool sys_read_seen, sys_write_seen; static void print_ksym(__u64 addr) @@ -91,10 +94,10 @@ static void print_stack(struct key_t *key, __u64 count) } } -static void int_exit(int sig) +static void err_exit(int err) { - kill(0, SIGKILL); - exit(0); + kill(pid, SIGKILL); + exit(err); } static void print_stacks(void) @@ -102,7 +105,7 @@ static void print_stacks(void) struct key_t key = {}, next_key; __u64 value; __u32 stackid = 0, next_id; - int fd = map_fd[0], stack_map = map_fd[1]; + int error = 1, fd = map_fd[0], stack_map = map_fd[1]; sys_read_seen = sys_write_seen = false; while (bpf_map_get_next_key(fd, &key, &next_key) == 0) { @@ -114,7 +117,7 @@ static void print_stacks(void) printf("\n"); if (!sys_read_seen || !sys_write_seen) { printf("BUG kernel stack doesn't contain sys_read() and sys_write()\n"); - int_exit(0); + err_exit(error); } /* clear stack map */ @@ -136,43 +139,52 @@ static inline int generate_load(void) static void test_perf_event_all_cpu(struct perf_event_attr *attr) { - int nr_cpus = sysconf(_SC_NPROCESSORS_CONF); - int *pmu_fd = malloc(nr_cpus * sizeof(int)); - int i, error = 0; + int nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); + struct bpf_link **links = calloc(nr_cpus, sizeof(struct bpf_link *)); + int i, pmu_fd, error = 1; + + if (!links) { + printf("malloc of links failed\n"); + goto err; + } /* system wide perf event, no need to inherit */ attr->inherit = 0; /* open perf_event on all cpus */ for (i = 0; i < nr_cpus; i++) { - pmu_fd[i] = sys_perf_event_open(attr, -1, i, -1, 0); - if (pmu_fd[i] < 0) { + pmu_fd = sys_perf_event_open(attr, -1, i, -1, 0); + if (pmu_fd < 0) { printf("sys_perf_event_open failed\n"); - error = 1; goto all_cpu_err; } - assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0); - assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE) == 0); + links[i] = bpf_program__attach_perf_event(prog, pmu_fd); + if (IS_ERR(links[i])) { + printf("bpf_program__attach_perf_event failed\n"); + links[i] = NULL; + close(pmu_fd); + goto all_cpu_err; + } } - if (generate_load() < 0) { - error = 1; + if (generate_load() < 0) goto all_cpu_err; - } + print_stacks(); + error = 0; all_cpu_err: - for (i--; i >= 0; i--) { - ioctl(pmu_fd[i], PERF_EVENT_IOC_DISABLE); - close(pmu_fd[i]); - } - free(pmu_fd); + for (i--; i >= 0; i--) + bpf_link__destroy(links[i]); +err: + free(links); if (error) - int_exit(0); + err_exit(error); } static void test_perf_event_task(struct perf_event_attr *attr) { - int pmu_fd, error = 0; + struct bpf_link *link = NULL; + int pmu_fd, error = 1; /* per task perf event, enable inherit so the "dd ..." command can be traced properly. * Enabling inherit will cause bpf_perf_prog_read_time helper failure. @@ -183,21 +195,25 @@ static void test_perf_event_task(struct perf_event_attr *attr) pmu_fd = sys_perf_event_open(attr, 0, -1, -1, 0); if (pmu_fd < 0) { printf("sys_perf_event_open failed\n"); - int_exit(0); + goto err; } - assert(ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0); - assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE) == 0); - - if (generate_load() < 0) { - error = 1; + link = bpf_program__attach_perf_event(prog, pmu_fd); + if (IS_ERR(link)) { + printf("bpf_program__attach_perf_event failed\n"); + link = NULL; + close(pmu_fd); goto err; } + + if (generate_load() < 0) + goto err; + print_stacks(); + error = 0; err: - ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE); - close(pmu_fd); + bpf_link__destroy(link); if (error) - int_exit(0); + err_exit(error); } static void test_bpf_perf_event(void) @@ -282,29 +298,60 @@ static void test_bpf_perf_event(void) int main(int argc, char **argv) { struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; + struct bpf_object *obj = NULL; char filename[256]; + int error = 1; snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); setrlimit(RLIMIT_MEMLOCK, &r); - signal(SIGINT, int_exit); - signal(SIGTERM, int_exit); + signal(SIGINT, err_exit); + signal(SIGTERM, err_exit); if (load_kallsyms()) { printf("failed to process /proc/kallsyms\n"); - return 1; + goto cleanup; + } + + obj = bpf_object__open_file(filename, NULL); + if (IS_ERR(obj)) { + printf("opening BPF object file failed\n"); + obj = NULL; + goto cleanup; + } + + prog = bpf_object__find_program_by_name(obj, "bpf_prog1"); + if (!prog) { + printf("finding a prog in obj file failed\n"); + goto cleanup; + } + + /* load BPF program */ + if (bpf_object__load(obj)) { + printf("loading BPF object file failed\n"); + goto cleanup; } - if (load_bpf_file(filename)) { - printf("%s", bpf_log_buf); - return 2; + map_fd[0] = bpf_object__find_map_fd_by_name(obj, "counts"); + map_fd[1] = bpf_object__find_map_fd_by_name(obj, "stackmap"); + if (map_fd[0] < 0 || map_fd[1] < 0) { + printf("finding a counts/stackmap map in obj file failed\n"); + goto cleanup; } - if (fork() == 0) { + pid = fork(); + if (pid == 0) { read_trace_pipe(); return 0; + } else if (pid == -1) { + printf("couldn't spawn process\n"); + goto cleanup; } + test_bpf_perf_event(); - int_exit(0); - return 0; + error = 0; + +cleanup: + bpf_object__close(obj); + err_exit(error); } |