diff options
Diffstat (limited to 'samples/bpf/bpf_load.c')
| -rw-r--r-- | samples/bpf/bpf_load.c | 39 |
1 files changed, 28 insertions, 11 deletions
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c index e6d7e0fe155b..eae7b635343d 100644 --- a/samples/bpf/bpf_load.c +++ b/samples/bpf/bpf_load.c @@ -54,6 +54,25 @@ static int populate_prog_array(const char *event, int prog_fd) return 0; } +static int write_kprobe_events(const char *val) +{ + int fd, ret, flags; + + if (val == NULL) + return -1; + else if (val[0] == '\0') + flags = O_WRONLY | O_TRUNC; + else + flags = O_WRONLY | O_APPEND; + + fd = open("/sys/kernel/debug/tracing/kprobe_events", flags); + + ret = write(fd, val, strlen(val)); + close(fd); + + return ret; +} + static int load_and_attach(const char *event, struct bpf_insn *prog, int size) { bool is_socket = strncmp(event, "socket", 6) == 0; @@ -165,10 +184,9 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size) #ifdef __x86_64__ if (strncmp(event, "sys_", 4) == 0) { - snprintf(buf, sizeof(buf), - "echo '%c:__x64_%s __x64_%s' >> /sys/kernel/debug/tracing/kprobe_events", - is_kprobe ? 'p' : 'r', event, event); - err = system(buf); + snprintf(buf, sizeof(buf), "%c:__x64_%s __x64_%s", + is_kprobe ? 'p' : 'r', event, event); + err = write_kprobe_events(buf); if (err >= 0) { need_normal_check = false; event_prefix = "__x64_"; @@ -176,10 +194,9 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size) } #endif if (need_normal_check) { - snprintf(buf, sizeof(buf), - "echo '%c:%s %s' >> /sys/kernel/debug/tracing/kprobe_events", - is_kprobe ? 'p' : 'r', event, event); - err = system(buf); + snprintf(buf, sizeof(buf), "%c:%s %s", + is_kprobe ? 'p' : 'r', event, event); + err = write_kprobe_events(buf); if (err < 0) { printf("failed to create kprobe '%s' error '%s'\n", event, strerror(errno)); @@ -284,8 +301,8 @@ static int load_maps(struct bpf_map_data *maps, int nr_maps, numa_node); } if (map_fd[i] < 0) { - printf("failed to create a map: %d %s\n", - errno, strerror(errno)); + printf("failed to create map %d (%s): %d %s\n", + i, maps[i].name, errno, strerror(errno)); return 1; } maps[i].fd = map_fd[i]; @@ -519,7 +536,7 @@ static int do_load_bpf_file(const char *path, fixup_map_cb fixup_map) return 1; /* clear all kprobes */ - i = system("echo \"\" > /sys/kernel/debug/tracing/kprobe_events"); + i = write_kprobe_events(""); /* scan over all elf sections to get license and map info */ for (i = 1; i < ehdr.e_shnum; i++) { |