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Diffstat (limited to 'tools/perf/util/bpf-loader.c')
-rw-r--r--tools/perf/util/bpf-loader.c143
1 files changed, 124 insertions, 19 deletions
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index ba6f7526b282..4c50411371db 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -26,18 +26,40 @@ static int libbpf_##name(const char *fmt, ...) \
return ret; \
}
-DEFINE_PRINT_FN(warning, 0)
-DEFINE_PRINT_FN(info, 0)
+DEFINE_PRINT_FN(warning, 1)
+DEFINE_PRINT_FN(info, 1)
DEFINE_PRINT_FN(debug, 1)
struct bpf_prog_priv {
struct perf_probe_event pev;
};
+static bool libbpf_initialized;
+
+struct bpf_object *
+bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name)
+{
+ struct bpf_object *obj;
+
+ if (!libbpf_initialized) {
+ libbpf_set_print(libbpf_warning,
+ libbpf_info,
+ libbpf_debug);
+ libbpf_initialized = true;
+ }
+
+ obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, name);
+ if (IS_ERR(obj)) {
+ pr_debug("bpf: failed to load buffer\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ return obj;
+}
+
struct bpf_object *bpf__prepare_load(const char *filename, bool source)
{
struct bpf_object *obj;
- static bool libbpf_initialized;
if (!libbpf_initialized) {
libbpf_set_print(libbpf_warning,
@@ -53,15 +75,15 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source)
err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
if (err)
- return ERR_PTR(err);
+ return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename);
free(obj_buf);
} else
obj = bpf_object__open(filename);
- if (!obj) {
+ if (IS_ERR(obj)) {
pr_debug("bpf: failed to load %s\n", filename);
- return ERR_PTR(-EINVAL);
+ return obj;
}
return obj;
@@ -96,9 +118,9 @@ config_bpf_program(struct bpf_program *prog)
int err;
config_str = bpf_program__title(prog, false);
- if (!config_str) {
+ if (IS_ERR(config_str)) {
pr_debug("bpf: unable to get title for program\n");
- return -EINVAL;
+ return PTR_ERR(config_str);
}
priv = calloc(sizeof(*priv), 1);
@@ -113,14 +135,14 @@ config_bpf_program(struct bpf_program *prog)
if (err < 0) {
pr_debug("bpf: '%s' is not a valid config string\n",
config_str);
- err = -EINVAL;
+ err = -BPF_LOADER_ERRNO__CONFIG;
goto errout;
}
if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
config_str, PERF_BPF_PROBE_GROUP);
- err = -EINVAL;
+ err = -BPF_LOADER_ERRNO__GROUP;
goto errout;
} else if (!pev->group)
pev->group = strdup(PERF_BPF_PROBE_GROUP);
@@ -132,9 +154,9 @@ config_bpf_program(struct bpf_program *prog)
}
if (!pev->event) {
- pr_debug("bpf: '%s': event name is missing\n",
+ pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n",
config_str);
- err = -EINVAL;
+ err = -BPF_LOADER_ERRNO__EVENTNAME;
goto errout;
}
pr_debug("bpf: config '%s' is ok\n", config_str);
@@ -285,7 +307,7 @@ int bpf__foreach_tev(struct bpf_object *obj,
(void **)&priv);
if (err || !priv) {
pr_debug("bpf: failed to get private field\n");
- return -EINVAL;
+ return -BPF_LOADER_ERRNO__INTERNAL;
}
pev = &priv->pev;
@@ -308,13 +330,57 @@ int bpf__foreach_tev(struct bpf_object *obj,
return 0;
}
+#define ERRNO_OFFSET(e) ((e) - __BPF_LOADER_ERRNO__START)
+#define ERRCODE_OFFSET(c) ERRNO_OFFSET(BPF_LOADER_ERRNO__##c)
+#define NR_ERRNO (__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START)
+
+static const char *bpf_loader_strerror_table[NR_ERRNO] = {
+ [ERRCODE_OFFSET(CONFIG)] = "Invalid config string",
+ [ERRCODE_OFFSET(GROUP)] = "Invalid group name",
+ [ERRCODE_OFFSET(EVENTNAME)] = "No event name found in config string",
+ [ERRCODE_OFFSET(INTERNAL)] = "BPF loader internal error",
+ [ERRCODE_OFFSET(COMPILE)] = "Error when compiling BPF scriptlet",
+};
+
+static int
+bpf_loader_strerror(int err, char *buf, size_t size)
+{
+ char sbuf[STRERR_BUFSIZE];
+ const char *msg;
+
+ if (!buf || !size)
+ return -1;
+
+ err = err > 0 ? err : -err;
+
+ if (err >= __LIBBPF_ERRNO__START)
+ return libbpf_strerror(err, buf, size);
+
+ if (err >= __BPF_LOADER_ERRNO__START && err < __BPF_LOADER_ERRNO__END) {
+ msg = bpf_loader_strerror_table[ERRNO_OFFSET(err)];
+ snprintf(buf, size, "%s", msg);
+ buf[size - 1] = '\0';
+ return 0;
+ }
+
+ if (err >= __BPF_LOADER_ERRNO__END)
+ snprintf(buf, size, "Unknown bpf loader error %d", err);
+ else
+ snprintf(buf, size, "%s",
+ strerror_r(err, sbuf, sizeof(sbuf)));
+
+ buf[size - 1] = '\0';
+ return -1;
+}
+
#define bpf__strerror_head(err, buf, size) \
char sbuf[STRERR_BUFSIZE], *emsg;\
if (!size)\
return 0;\
if (err < 0)\
err = -err;\
- emsg = strerror_r(err, sbuf, sizeof(sbuf));\
+ bpf_loader_strerror(err, sbuf, sizeof(sbuf));\
+ emsg = sbuf;\
switch (err) {\
default:\
scnprintf(buf, size, "%s", emsg);\
@@ -330,23 +396,62 @@ int bpf__foreach_tev(struct bpf_object *obj,
}\
buf[size - 1] = '\0';
+int bpf__strerror_prepare_load(const char *filename, bool source,
+ int err, char *buf, size_t size)
+{
+ size_t n;
+ int ret;
+
+ n = snprintf(buf, size, "Failed to load %s%s: ",
+ filename, source ? " from source" : "");
+ if (n >= size) {
+ buf[size - 1] = '\0';
+ return 0;
+ }
+ buf += n;
+ size -= n;
+
+ ret = bpf_loader_strerror(err, buf, size);
+ buf[size - 1] = '\0';
+ return ret;
+}
+
int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
int err, char *buf, size_t size)
{
bpf__strerror_head(err, buf, size);
bpf__strerror_entry(EEXIST, "Probe point exist. Try use 'perf probe -d \"*\"'");
- bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0\n");
- bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file\n");
+ bpf__strerror_entry(EACCES, "You need to be root");
+ bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
+ bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
bpf__strerror_end(buf, size);
return 0;
}
-int bpf__strerror_load(struct bpf_object *obj __maybe_unused,
+int bpf__strerror_load(struct bpf_object *obj,
int err, char *buf, size_t size)
{
bpf__strerror_head(err, buf, size);
- bpf__strerror_entry(EINVAL, "%s: Are you root and runing a CONFIG_BPF_SYSCALL kernel?",
- emsg)
+ case LIBBPF_ERRNO__KVER: {
+ unsigned int obj_kver = bpf_object__get_kversion(obj);
+ unsigned int real_kver;
+
+ if (fetch_kernel_version(&real_kver, NULL, 0)) {
+ scnprintf(buf, size, "Unable to fetch kernel version");
+ break;
+ }
+
+ if (obj_kver != real_kver) {
+ scnprintf(buf, size,
+ "'version' ("KVER_FMT") doesn't match running kernel ("KVER_FMT")",
+ KVER_PARAM(obj_kver),
+ KVER_PARAM(real_kver));
+ break;
+ }
+
+ scnprintf(buf, size, "Failed to load program for unknown reason");
+ break;
+ }
bpf__strerror_end(buf, size);
return 0;
}
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