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-rw-r--r--tools/perf/util/probe-event.c406
1 files changed, 215 insertions, 191 deletions
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 8319fbb08636..74401a20106d 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -265,6 +265,65 @@ static bool kprobe_warn_out_range(const char *symbol, unsigned long address)
return true;
}
+/*
+ * NOTE:
+ * '.gnu.linkonce.this_module' section of kernel module elf directly
+ * maps to 'struct module' from linux/module.h. This section contains
+ * actual module name which will be used by kernel after loading it.
+ * But, we cannot use 'struct module' here since linux/module.h is not
+ * exposed to user-space. Offset of 'name' has remained same from long
+ * time, so hardcoding it here.
+ */
+#ifdef __LP64__
+#define MOD_NAME_OFFSET 24
+#else
+#define MOD_NAME_OFFSET 12
+#endif
+
+/*
+ * @module can be module name of module file path. In case of path,
+ * inspect elf and find out what is actual module name.
+ * Caller has to free mod_name after using it.
+ */
+static char *find_module_name(const char *module)
+{
+ int fd;
+ Elf *elf;
+ GElf_Ehdr ehdr;
+ GElf_Shdr shdr;
+ Elf_Data *data;
+ Elf_Scn *sec;
+ char *mod_name = NULL;
+
+ fd = open(module, O_RDONLY);
+ if (fd < 0)
+ return NULL;
+
+ elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
+ if (elf == NULL)
+ goto elf_err;
+
+ if (gelf_getehdr(elf, &ehdr) == NULL)
+ goto ret_err;
+
+ sec = elf_section_by_name(elf, &ehdr, &shdr,
+ ".gnu.linkonce.this_module", NULL);
+ if (!sec)
+ goto ret_err;
+
+ data = elf_getdata(sec, NULL);
+ if (!data || !data->d_buf)
+ goto ret_err;
+
+ mod_name = strdup((char *)data->d_buf + MOD_NAME_OFFSET);
+
+ret_err:
+ elf_end(elf);
+elf_err:
+ close(fd);
+ return mod_name;
+}
+
#ifdef HAVE_DWARF_SUPPORT
static int kernel_get_module_dso(const char *module, struct dso **pdso)
@@ -486,8 +545,10 @@ static int get_text_start_address(const char *exec, unsigned long *address)
return -errno;
elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
- if (elf == NULL)
- return -EINVAL;
+ if (elf == NULL) {
+ ret = -EINVAL;
+ goto out_close;
+ }
if (gelf_getehdr(elf, &ehdr) == NULL)
goto out;
@@ -499,6 +560,9 @@ static int get_text_start_address(const char *exec, unsigned long *address)
ret = 0;
out:
elf_end(elf);
+out_close:
+ close(fd);
+
return ret;
}
@@ -583,32 +647,23 @@ static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
int ntevs, const char *module)
{
int i, ret = 0;
- char *tmp;
+ char *mod_name = NULL;
if (!module)
return 0;
- tmp = strrchr(module, '/');
- if (tmp) {
- /* This is a module path -- get the module name */
- module = strdup(tmp + 1);
- if (!module)
- return -ENOMEM;
- tmp = strchr(module, '.');
- if (tmp)
- *tmp = '\0';
- tmp = (char *)module; /* For free() */
- }
+ mod_name = find_module_name(module);
for (i = 0; i < ntevs; i++) {
- tevs[i].point.module = strdup(module);
+ tevs[i].point.module =
+ strdup(mod_name ? mod_name : module);
if (!tevs[i].point.module) {
ret = -ENOMEM;
break;
}
}
- free(tmp);
+ free(mod_name);
return ret;
}
@@ -1618,69 +1673,65 @@ out:
}
/* Compose only probe arg */
-int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len)
+char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
{
struct perf_probe_arg_field *field = pa->field;
- int ret;
- char *tmp = buf;
+ struct strbuf buf;
+ char *ret = NULL;
+ int err;
+
+ if (strbuf_init(&buf, 64) < 0)
+ return NULL;
if (pa->name && pa->var)
- ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var);
+ err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var);
else
- ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var);
- if (ret <= 0)
- goto error;
- tmp += ret;
- len -= ret;
+ err = strbuf_addstr(&buf, pa->name ?: pa->var);
+ if (err)
+ goto out;
while (field) {
if (field->name[0] == '[')
- ret = e_snprintf(tmp, len, "%s", field->name);
+ err = strbuf_addstr(&buf, field->name);
else
- ret = e_snprintf(tmp, len, "%s%s",
- field->ref ? "->" : ".", field->name);
- if (ret <= 0)
- goto error;
- tmp += ret;
- len -= ret;
+ err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".",
+ field->name);
field = field->next;
+ if (err)
+ goto out;
}
- if (pa->type) {
- ret = e_snprintf(tmp, len, ":%s", pa->type);
- if (ret <= 0)
- goto error;
- tmp += ret;
- len -= ret;
- }
+ if (pa->type)
+ if (strbuf_addf(&buf, ":%s", pa->type) < 0)
+ goto out;
- return tmp - buf;
-error:
- pr_debug("Failed to synthesize perf probe argument: %d\n", ret);
+ ret = strbuf_detach(&buf, NULL);
+out:
+ strbuf_release(&buf);
return ret;
}
/* Compose only probe point (not argument) */
static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
{
- char *buf, *tmp;
- char offs[32] = "", line[32] = "", file[32] = "";
- int ret, len;
+ struct strbuf buf;
+ char *tmp, *ret = NULL;
+ int len, err = 0;
- buf = zalloc(MAX_CMDLEN);
- if (buf == NULL) {
- ret = -ENOMEM;
- goto error;
- }
- if (pp->offset) {
- ret = e_snprintf(offs, 32, "+%lu", pp->offset);
- if (ret <= 0)
- goto error;
- }
- if (pp->line) {
- ret = e_snprintf(line, 32, ":%d", pp->line);
- if (ret <= 0)
- goto error;
+ if (strbuf_init(&buf, 64) < 0)
+ return NULL;
+
+ if (pp->function) {
+ if (strbuf_addstr(&buf, pp->function) < 0)
+ goto out;
+ if (pp->offset)
+ err = strbuf_addf(&buf, "+%lu", pp->offset);
+ else if (pp->line)
+ err = strbuf_addf(&buf, ":%d", pp->line);
+ else if (pp->retprobe)
+ err = strbuf_addstr(&buf, "%return");
+ if (err)
+ goto out;
}
if (pp->file) {
tmp = pp->file;
@@ -1689,25 +1740,15 @@ static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
tmp = strchr(pp->file + len - 30, '/');
tmp = tmp ? tmp + 1 : pp->file + len - 30;
}
- ret = e_snprintf(file, 32, "@%s", tmp);
- if (ret <= 0)
- goto error;
+ err = strbuf_addf(&buf, "@%s", tmp);
+ if (!err && !pp->function && pp->line)
+ err = strbuf_addf(&buf, ":%d", pp->line);
}
-
- if (pp->function)
- ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
- offs, pp->retprobe ? "%return" : "", line,
- file);
- else
- ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
- if (ret <= 0)
- goto error;
-
- return buf;
-error:
- pr_debug("Failed to synthesize perf probe point: %d\n", ret);
- free(buf);
- return NULL;
+ if (!err)
+ ret = strbuf_detach(&buf, NULL);
+out:
+ strbuf_release(&buf);
+ return ret;
}
#if 0
@@ -1736,45 +1777,32 @@ char *synthesize_perf_probe_command(struct perf_probe_event *pev)
#endif
static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
- char **buf, size_t *buflen,
- int depth)
+ struct strbuf *buf, int depth)
{
- int ret;
+ int err;
if (ref->next) {
depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
- buflen, depth + 1);
+ depth + 1);
if (depth < 0)
- goto out;
- }
-
- ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset);
- if (ret < 0)
- depth = ret;
- else {
- *buf += ret;
- *buflen -= ret;
+ return depth;
}
-out:
- return depth;
-
+ err = strbuf_addf(buf, "%+ld(", ref->offset);
+ return (err < 0) ? err : depth;
}
static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
- char *buf, size_t buflen)
+ struct strbuf *buf)
{
struct probe_trace_arg_ref *ref = arg->ref;
- int ret, depth = 0;
- char *tmp = buf;
+ int depth = 0, err;
/* Argument name or separator */
if (arg->name)
- ret = e_snprintf(buf, buflen, " %s=", arg->name);
+ err = strbuf_addf(buf, " %s=", arg->name);
else
- ret = e_snprintf(buf, buflen, " ");
- if (ret < 0)
- return ret;
- buf += ret;
- buflen -= ret;
+ err = strbuf_addch(buf, ' ');
+ if (err)
+ return err;
/* Special case: @XXX */
if (arg->value[0] == '@' && arg->ref)
@@ -1782,59 +1810,44 @@ static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
/* Dereferencing arguments */
if (ref) {
- depth = __synthesize_probe_trace_arg_ref(ref, &buf,
- &buflen, 1);
+ depth = __synthesize_probe_trace_arg_ref(ref, buf, 1);
if (depth < 0)
return depth;
}
/* Print argument value */
if (arg->value[0] == '@' && arg->ref)
- ret = e_snprintf(buf, buflen, "%s%+ld", arg->value,
- arg->ref->offset);
+ err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset);
else
- ret = e_snprintf(buf, buflen, "%s", arg->value);
- if (ret < 0)
- return ret;
- buf += ret;
- buflen -= ret;
+ err = strbuf_addstr(buf, arg->value);
/* Closing */
- while (depth--) {
- ret = e_snprintf(buf, buflen, ")");
- if (ret < 0)
- return ret;
- buf += ret;
- buflen -= ret;
- }
+ while (!err && depth--)
+ err = strbuf_addch(buf, ')');
+
/* Print argument type */
- if (arg->type) {
- ret = e_snprintf(buf, buflen, ":%s", arg->type);
- if (ret <= 0)
- return ret;
- buf += ret;
- }
+ if (!err && arg->type)
+ err = strbuf_addf(buf, ":%s", arg->type);
- return buf - tmp;
+ return err;
}
char *synthesize_probe_trace_command(struct probe_trace_event *tev)
{
struct probe_trace_point *tp = &tev->point;
- char *buf;
- int i, len, ret;
+ struct strbuf buf;
+ char *ret = NULL;
+ int i, err;
- buf = zalloc(MAX_CMDLEN);
- if (buf == NULL)
+ /* Uprobes must have tp->module */
+ if (tev->uprobes && !tp->module)
return NULL;
- len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
- tev->group, tev->event);
- if (len <= 0)
- goto error;
+ if (strbuf_init(&buf, 32) < 0)
+ return NULL;
- /* Uprobes must have tp->module */
- if (tev->uprobes && !tp->module)
+ if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
+ tev->group, tev->event) < 0)
goto error;
/*
* If tp->address == 0, then this point must be a
@@ -1849,34 +1862,25 @@ char *synthesize_probe_trace_command(struct probe_trace_event *tev)
/* Use the tp->address for uprobes */
if (tev->uprobes)
- ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s:0x%lx",
- tp->module, tp->address);
+ err = strbuf_addf(&buf, "%s:0x%lx", tp->module, tp->address);
else if (!strncmp(tp->symbol, "0x", 2))
/* Absolute address. See try_to_find_absolute_address() */
- ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s%s0x%lx",
- tp->module ?: "", tp->module ? ":" : "",
- tp->address);
+ err = strbuf_addf(&buf, "%s%s0x%lx", tp->module ?: "",
+ tp->module ? ":" : "", tp->address);
else
- ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s%s%s+%lu",
- tp->module ?: "", tp->module ? ":" : "",
- tp->symbol, tp->offset);
-
- if (ret <= 0)
+ err = strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "",
+ tp->module ? ":" : "", tp->symbol, tp->offset);
+ if (err)
goto error;
- len += ret;
- for (i = 0; i < tev->nargs; i++) {
- ret = synthesize_probe_trace_arg(&tev->args[i], buf + len,
- MAX_CMDLEN - len);
- if (ret <= 0)
+ for (i = 0; i < tev->nargs; i++)
+ if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0)
goto error;
- len += ret;
- }
- return buf;
+ ret = strbuf_detach(&buf, NULL);
error:
- free(buf);
- return NULL;
+ strbuf_release(&buf);
+ return ret;
}
static int find_perf_probe_point_from_map(struct probe_trace_point *tp,
@@ -1958,7 +1962,7 @@ static int convert_to_perf_probe_point(struct probe_trace_point *tp,
static int convert_to_perf_probe_event(struct probe_trace_event *tev,
struct perf_probe_event *pev, bool is_kprobe)
{
- char buf[64] = "";
+ struct strbuf buf = STRBUF_INIT;
int i, ret;
/* Convert event/group name */
@@ -1981,14 +1985,15 @@ static int convert_to_perf_probe_event(struct probe_trace_event *tev,
if (tev->args[i].name)
pev->args[i].name = strdup(tev->args[i].name);
else {
- ret = synthesize_probe_trace_arg(&tev->args[i],
- buf, 64);
- pev->args[i].name = strdup(buf);
+ if ((ret = strbuf_init(&buf, 32)) < 0)
+ goto error;
+ ret = synthesize_probe_trace_arg(&tev->args[i], &buf);
+ pev->args[i].name = strbuf_detach(&buf, NULL);
}
if (pev->args[i].name == NULL && ret >= 0)
ret = -ENOMEM;
}
-
+error:
if (ret < 0)
clear_perf_probe_event(pev);
@@ -2162,35 +2167,38 @@ static int perf_probe_event__sprintf(const char *group, const char *event,
struct strbuf *result)
{
int i, ret;
- char buf[128];
- char *place;
+ char *buf;
- /* Synthesize only event probe point */
- place = synthesize_perf_probe_point(&pev->point);
- if (!place)
- return -EINVAL;
+ if (asprintf(&buf, "%s:%s", group, event) < 0)
+ return -errno;
+ ret = strbuf_addf(result, " %-20s (on ", buf);
+ free(buf);
+ if (ret)
+ return ret;
- ret = e_snprintf(buf, 128, "%s:%s", group, event);
- if (ret < 0)
- goto out;
+ /* Synthesize only event probe point */
+ buf = synthesize_perf_probe_point(&pev->point);
+ if (!buf)
+ return -ENOMEM;
+ ret = strbuf_addstr(result, buf);
+ free(buf);
- strbuf_addf(result, " %-20s (on %s", buf, place);
- if (module)
- strbuf_addf(result, " in %s", module);
+ if (!ret && module)
+ ret = strbuf_addf(result, " in %s", module);
- if (pev->nargs > 0) {
- strbuf_add(result, " with", 5);
- for (i = 0; i < pev->nargs; i++) {
- ret = synthesize_perf_probe_arg(&pev->args[i],
- buf, 128);
- if (ret < 0)
- goto out;
- strbuf_addf(result, " %s", buf);
+ if (!ret && pev->nargs > 0) {
+ ret = strbuf_add(result, " with", 5);
+ for (i = 0; !ret && i < pev->nargs; i++) {
+ buf = synthesize_perf_probe_arg(&pev->args[i]);
+ if (!buf)
+ return -ENOMEM;
+ ret = strbuf_addf(result, " %s", buf);
+ free(buf);
}
}
- strbuf_addch(result, ')');
-out:
- free(place);
+ if (!ret)
+ ret = strbuf_addch(result, ')');
+
return ret;
}
@@ -2498,7 +2506,8 @@ static int find_probe_functions(struct map *map, char *name,
void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused,
struct probe_trace_event *tev __maybe_unused,
- struct map *map __maybe_unused) { }
+ struct map *map __maybe_unused,
+ struct symbol *sym __maybe_unused) { }
/*
* Find probe function addresses from map.
@@ -2516,6 +2525,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
struct probe_trace_point *tp;
int num_matched_functions;
int ret, i, j, skipped = 0;
+ char *mod_name;
map = get_target_map(pev->target, pev->uprobes);
if (!map) {
@@ -2600,9 +2610,19 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
tp->realname = strdup_or_goto(sym->name, nomem_out);
tp->retprobe = pp->retprobe;
- if (pev->target)
- tev->point.module = strdup_or_goto(pev->target,
- nomem_out);
+ if (pev->target) {
+ if (pev->uprobes) {
+ tev->point.module = strdup_or_goto(pev->target,
+ nomem_out);
+ } else {
+ mod_name = find_module_name(pev->target);
+ tev->point.module =
+ strdup(mod_name ? mod_name : pev->target);
+ free(mod_name);
+ if (!tev->point.module)
+ goto nomem_out;
+ }
+ }
tev->uprobes = pev->uprobes;
tev->nargs = pev->nargs;
if (tev->nargs) {
@@ -2624,7 +2644,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
strdup_or_goto(pev->args[i].type,
nomem_out);
}
- arch__fix_tev_from_maps(pev, tev, map);
+ arch__fix_tev_from_maps(pev, tev, map, sym);
}
if (ret == skipped) {
ret = -ENOENT;
@@ -2743,9 +2763,13 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
{
int ret;
- if (pev->uprobes && !pev->group) {
- /* Replace group name if not given */
- ret = convert_exec_to_group(pev->target, &pev->group);
+ if (!pev->group) {
+ /* Set group name if not given */
+ if (!pev->uprobes) {
+ pev->group = strdup(PERFPROBE_GROUP);
+ ret = pev->group ? 0 : -ENOMEM;
+ } else
+ ret = convert_exec_to_group(pev->target, &pev->group);
if (ret != 0) {
pr_warning("Failed to make a group name.\n");
return ret;