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Diffstat (limited to 'tools/perf/util/probe-event.c')
-rw-r--r--tools/perf/util/probe-event.c105
1 files changed, 69 insertions, 36 deletions
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index d281ae2b54e8..4a57c8a60bd9 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -163,7 +163,7 @@ static struct map *kernel_get_module_map(const char *module)
/* A file path -- this is an offline module */
if (module && strchr(module, '/'))
- return machine__findnew_module_map(host_machine, 0, module);
+ return dso__new_map(module);
if (!module)
module = "kernel";
@@ -173,6 +173,7 @@ static struct map *kernel_get_module_map(const char *module)
if (strncmp(pos->dso->short_name + 1, module,
pos->dso->short_name_len - 2) == 0 &&
module[pos->dso->short_name_len - 2] == '\0') {
+ map__get(pos);
return pos;
}
}
@@ -188,15 +189,6 @@ struct map *get_target_map(const char *target, bool user)
return kernel_get_module_map(target);
}
-static void put_target_map(struct map *map, bool user)
-{
- if (map && user) {
- /* Only the user map needs to be released */
- map__put(map);
- }
-}
-
-
static int convert_exec_to_group(const char *exec, char **result)
{
char *ptr1, *ptr2, *exec_copy;
@@ -268,21 +260,6 @@ static bool kprobe_warn_out_range(const char *symbol, unsigned long address)
}
/*
- * 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.
@@ -296,6 +273,7 @@ static char *find_module_name(const char *module)
Elf_Data *data;
Elf_Scn *sec;
char *mod_name = NULL;
+ int name_offset;
fd = open(module, O_RDONLY);
if (fd < 0)
@@ -317,7 +295,21 @@ static char *find_module_name(const char *module)
if (!data || !data->d_buf)
goto ret_err;
- mod_name = strdup((char *)data->d_buf + MOD_NAME_OFFSET);
+ /*
+ * 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.
+ */
+ if (ehdr.e_ident[EI_CLASS] == ELFCLASS32)
+ name_offset = 12;
+ else /* expect ELFCLASS64 by default */
+ name_offset = 24;
+
+ mod_name = strdup((char *)data->d_buf + name_offset);
ret_err:
elf_end(elf);
@@ -412,7 +404,7 @@ static int find_alternative_probe_point(struct debuginfo *dinfo,
}
out:
- put_target_map(map, uprobes);
+ map__put(map);
return ret;
}
@@ -618,6 +610,51 @@ error:
return ret ? : -ENOENT;
}
+/*
+ * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions
+ * and generate new symbols with suffixes such as .constprop.N or .isra.N
+ * etc. Since those symbols are not recorded in DWARF, we have to find
+ * correct generated symbols from offline ELF binary.
+ * For online kernel or uprobes we don't need this because those are
+ * rebased on _text, or already a section relative address.
+ */
+static int
+post_process_offline_probe_trace_events(struct probe_trace_event *tevs,
+ int ntevs, const char *pathname)
+{
+ struct symbol *sym;
+ struct map *map;
+ unsigned long stext = 0;
+ u64 addr;
+ int i;
+
+ /* Prepare a map for offline binary */
+ map = dso__new_map(pathname);
+ if (!map || get_text_start_address(pathname, &stext) < 0) {
+ pr_warning("Failed to get ELF symbols for %s\n", pathname);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < ntevs; i++) {
+ addr = tevs[i].point.address + tevs[i].point.offset - stext;
+ sym = map__find_symbol(map, addr);
+ if (!sym)
+ continue;
+ if (!strcmp(sym->name, tevs[i].point.symbol))
+ continue;
+ /* If we have no realname, use symbol for it */
+ if (!tevs[i].point.realname)
+ tevs[i].point.realname = tevs[i].point.symbol;
+ else
+ free(tevs[i].point.symbol);
+ tevs[i].point.symbol = strdup(sym->name);
+ tevs[i].point.offset = addr - sym->start;
+ }
+ map__put(map);
+
+ return 0;
+}
+
static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
int ntevs, const char *exec)
{
@@ -679,7 +716,8 @@ post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
/* Skip post process if the target is an offline kernel */
if (symbol_conf.ignore_vmlinux_buildid)
- return 0;
+ return post_process_offline_probe_trace_events(tevs, ntevs,
+ symbol_conf.vmlinux_name);
reloc_sym = kernel_get_ref_reloc_sym();
if (!reloc_sym) {
@@ -2869,7 +2907,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
}
out:
- put_target_map(map, pev->uprobes);
+ map__put(map);
free(syms);
return ret;
@@ -3362,10 +3400,7 @@ int show_available_funcs(const char *target, struct strfilter *_filter,
return ret;
/* Get a symbol map */
- if (user)
- map = dso__new_map(target);
- else
- map = kernel_get_module_map(target);
+ map = get_target_map(target, user);
if (!map) {
pr_err("Failed to get a map for %s\n", (target) ? : "kernel");
return -EINVAL;
@@ -3397,9 +3432,7 @@ int show_available_funcs(const char *target, struct strfilter *_filter,
}
end:
- if (user) {
- map__put(map);
- }
+ map__put(map);
exit_probe_symbol_maps();
return ret;