diff options
| author | Pierre-Loup A. Griffais <pgriffais@nvidia.com> | 2012-06-22 11:38:13 -0700 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2012-06-27 13:14:18 -0300 |
| commit | 209bd9e3e14712d74c8bebb028afda905d689f1c (patch) | |
| tree | b106bcd49dc71e958f0c78f67cdaae6eba940c62 /tools/perf | |
| parent | da3789628f88684d3f0fb4e6a6bc086c395ac3cb (diff) | |
perf symbols: Follow .gnu_debuglink section to find separate symbols
The .gnu_debuglink section is specified to contain the filename of the
debug info file, as well as a CRC that can be used to validate it.
This doesn't currently use the checksum and relies on the usual build-id
matching for validation.
This provides more context:
http://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html
Signed-off-by: Pierre-Loup A. Griffais <pgriffais@nvidia.com>
Reported-by: Mike Sartain <mikesart@valvesoftware.com>
Tested-by: Mike Sartain <mikesart@valvesoftware.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Sartain <mikesart@valvesoftware.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4FE4BB95.3080309@nvidia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf')
| -rw-r--r-- | tools/perf/util/symbol.c | 65 | ||||
| -rw-r--r-- | tools/perf/util/symbol.h | 1 |
2 files changed, 65 insertions, 1 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 3e2e5ea0f03f..994f4ffdcd05 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1590,11 +1590,62 @@ out: return err; } +static int filename__read_debuglink(const char *filename, + char *debuglink, size_t size) +{ + int fd, err = -1; + Elf *elf; + GElf_Ehdr ehdr; + GElf_Shdr shdr; + Elf_Data *data; + Elf_Scn *sec; + Elf_Kind ek; + + fd = open(filename, O_RDONLY); + if (fd < 0) + goto out; + + elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); + if (elf == NULL) { + pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename); + goto out_close; + } + + ek = elf_kind(elf); + if (ek != ELF_K_ELF) + goto out_close; + + if (gelf_getehdr(elf, &ehdr) == NULL) { + pr_err("%s: cannot get elf header.\n", __func__); + goto out_close; + } + + sec = elf_section_by_name(elf, &ehdr, &shdr, + ".gnu_debuglink", NULL); + if (sec == NULL) + goto out_close; + + data = elf_getdata(sec, NULL); + if (data == NULL) + goto out_close; + + /* the start of this section is a zero-terminated string */ + strncpy(debuglink, data->d_buf, size); + + elf_end(elf); + +out_close: + close(fd); +out: + return err; +} + char dso__symtab_origin(const struct dso *dso) { static const char origin[] = { [SYMTAB__KALLSYMS] = 'k', [SYMTAB__JAVA_JIT] = 'j', + [SYMTAB__DEBUGLINK] = 'l', [SYMTAB__BUILD_ID_CACHE] = 'B', [SYMTAB__FEDORA_DEBUGINFO] = 'f', [SYMTAB__UBUNTU_DEBUGINFO] = 'u', @@ -1662,10 +1713,22 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) */ want_symtab = 1; restart: - for (dso->symtab_type = SYMTAB__BUILD_ID_CACHE; + for (dso->symtab_type = SYMTAB__DEBUGLINK; dso->symtab_type != SYMTAB__NOT_FOUND; dso->symtab_type++) { switch (dso->symtab_type) { + case SYMTAB__DEBUGLINK: { + char *debuglink; + strncpy(name, dso->long_name, size); + debuglink = name + dso->long_name_len; + while (debuglink != name && *debuglink != '/') + debuglink--; + if (*debuglink == '/') + debuglink++; + filename__read_debuglink(dso->long_name, debuglink, + size - (debuglink - name)); + } + break; case SYMTAB__BUILD_ID_CACHE: /* skip the locally configured cache if a symfs is given */ if (symbol_conf.symfs[0] || diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index af0752b1aca1..a884b99017f0 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -257,6 +257,7 @@ enum symtab_type { SYMTAB__KALLSYMS = 0, SYMTAB__GUEST_KALLSYMS, SYMTAB__JAVA_JIT, + SYMTAB__DEBUGLINK, SYMTAB__BUILD_ID_CACHE, SYMTAB__FEDORA_DEBUGINFO, SYMTAB__UBUNTU_DEBUGINFO, |