diff options
| -rw-r--r-- | tools/perf/util/probe-event.c | 48 |
1 files changed, 47 insertions, 1 deletions
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 542e6472c4d7..4a57c8a60bd9 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -610,6 +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) { @@ -671,7 +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) { |