libbpf-tools: update ksnoop for libbpf 1.0

Switch to libbpf 1.0 mode and adapt libbpf API usage accordingly.

Signed-off-by: Andrii Nakryiko <[email protected]>

libbpf-tools/ksnoop.c

@@ -37,7 +37,6 @@ static enum log_level log_level = WARN;
 static __u32 filter_pid;
 static bool stack_mode;
 
-#define libbpf_errstr(val) strerror(-libbpf_get_error(val))
 
 static void __p(enum log_level level, char *level_str, char *fmt, ...)
 {
@@ -222,14 +221,12 @@ static int get_func_btf(struct btf *btf, struct func *func)
  return -ENOENT;
  }
  type = btf__type_by_id(btf, func->id);
- if (libbpf_get_error(type) ||
- BTF_INFO_KIND(type->info) != BTF_KIND_FUNC) {
+ if (!type || BTF_INFO_KIND(type->info) != BTF_KIND_FUNC) {
  p_err("Error looking up function type via id '%d'", func->id);
  return -EINVAL;
  }
  type = btf__type_by_id(btf, type->type);
- if (libbpf_get_error(type) ||
- BTF_INFO_KIND(type->info) != BTF_KIND_FUNC_PROTO) {
+ if (!type || BTF_INFO_KIND(type->info) != BTF_KIND_FUNC_PROTO) {
  p_err("Error looking up function proto type via id '%d'",
  func->id);
  return -EINVAL;
@@ -343,25 +340,26 @@ static int trace_to_value(struct btf *btf, struct func *func, char *argname,
 static struct btf *get_btf(const char *name)
 {
  struct btf *mod_btf;
+ int err;
 
  p_debug("getting BTF for %s",
  name && strlen(name) > 0 ? name : "vmlinux");
 
  if (!vmlinux_btf) {
  vmlinux_btf = btf__load_vmlinux_btf();
- if (libbpf_get_error(vmlinux_btf)) {
- p_err("No BTF, cannot determine type info: %s",
-  libbpf_errstr(vmlinux_btf));
+ if (!vmlinux_btf) {
+ err = -errno;
+ p_err("No BTF, cannot determine type info: %s", strerror(-err));
  return NULL;
  }
  }
  if (!name || strlen(name) == 0)
  return vmlinux_btf;
 
  mod_btf = btf__load_module_btf(name, vmlinux_btf);
- if (libbpf_get_error(mod_btf)) {
- p_err("No BTF for module '%s': %s",
-   name, libbpf_errstr(mod_btf));
+ if (!mod_btf) {
+ err = -errno;
+ p_err("No BTF for module '%s': %s", name, strerror(-err));
  return NULL;
  }
  return mod_btf;
@@ -395,11 +393,11 @@ static char *type_id_to_str(struct btf *btf, __s32 type_id, char *str)
  default:
  do {
  type = btf__type_by_id(btf, type_id);
-
- if (libbpf_get_error(type)) {
+ if (!type) {
  name = "?";
  break;
  }
+
  switch (BTF_INFO_KIND(type->info)) {
  case BTF_KIND_CONST:
  case BTF_KIND_VOLATILE:
@@ -554,16 +552,17 @@ static int parse_trace(char *str, struct trace *trace)
  return ret;
  }
  trace->btf = get_btf(func->mod);
- if (libbpf_get_error(trace->btf)) {
+ if (!trace->btf) {
+ ret = -errno;
  p_err("could not get BTF for '%s': %s",
  strlen(func->mod) ? func->mod : "vmlinux",
- libbpf_errstr(trace->btf));
+ strerror(-ret));
  return -ENOENT;
  }
  trace->dump = btf_dump__new(trace->btf, NULL, &opts, trace_printf);
- if (libbpf_get_error(trace->dump)) {
- p_err("could not create BTF dump : %n",
-  libbpf_errstr(trace->btf));
+ if (!trace->dump) {
+ ret = -errno;
+ p_err("could not create BTF dump : %n", strerror(-ret));
  return -EINVAL;
  }
 
@@ -823,20 +822,20 @@ static int attach_traces(struct ksnoop_bpf *skel, struct trace *traces,
  bpf_program__attach_kprobe(skel->progs.kprobe_entry,
  false,
  traces[i].func.name);
- ret = libbpf_get_error(traces[i].links[0]);
- if (ret) {
+ if (!traces[i].links[0]) {
+  ret = -errno;
  p_err("Could not attach kprobe to '%s': %s",
  traces[i].func.name, strerror(-ret));
  return ret;
-  }
+ }
  p_debug("Attached kprobe for '%s'", traces[i].func.name);
 
  traces[i].links[1] =
  bpf_program__attach_kprobe(skel->progs.kprobe_return,
  true,
  traces[i].func.name);
- ret = libbpf_get_error(traces[i].links[1]);
- if (ret) {
+ if (!traces[i].links[1]) {
+  ret = -errno;
  p_err("Could not attach kretprobe to '%s': %s",
  traces[i].func.name, strerror(-ret));
  return ret;
@@ -848,7 +847,6 @@ static int attach_traces(struct ksnoop_bpf *skel, struct trace *traces,
 
 static int cmd_trace(int argc, char **argv)
 {
- struct perf_buffer_opts pb_opts = {};
  struct bpf_map *perf_map, *func_map;
  struct perf_buffer *pb = NULL;
  struct ksnoop_bpf *skel;
@@ -861,7 +859,8 @@ static int cmd_trace(int argc, char **argv)
 
  skel = ksnoop_bpf__open_and_load();
  if (!skel) {
- p_err("Could not load ksnoop BPF: %s", libbpf_errstr(skel));
+ ret = -errno;
+ p_err("Could not load ksnoop BPF: %s", strerror(-ret));
  return 1;
  }
 
@@ -886,12 +885,11 @@ static int cmd_trace(int argc, char **argv)
  goto cleanup;
  }
 
- pb_opts.sample_cb = trace_handler;
- pb_opts.lost_cb = lost_handler;
- pb = perf_buffer__new(bpf_map__fd(perf_map), pages, &pb_opts);
- if (libbpf_get_error(pb)) {
- p_err("Could not create perf buffer: %s",
- libbpf_errstr(pb));
+ pb = perf_buffer__new(bpf_map__fd(perf_map), pages,
+ trace_handler, lost_handler, NULL, NULL);
+ if (!pb) {
+ ret = -errno;
+ p_err("Could not create perf buffer: %s", strerror(-ret));
  goto cleanup;
  }
 
@@ -905,8 +903,8 @@ static int cmd_trace(int argc, char **argv)
 
  while (!exiting) {
  ret = perf_buffer__poll(pb, 1);
- if (ret < 0 && errno != EINTR) {
- fprintf(stderr, "error polling perf buffer: %s\n", strerror(errno));
+ if (ret < 0 && ret != -EINTR) {
+ fprintf(stderr, "error polling perf buffer: %s\n", strerror(-ret));
  goto cleanup;
  }
  /* reset ret to return 0 if exiting */
@@ -1000,5 +998,7 @@ int main(int argc, char *argv[])
  if (argc < 0)
  usage();
 
+ libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
+
  return cmd_select(argc, argv);
 }