[PATCH] perf tools: Fix debuginfo search for Ubuntu

From: Adrian Hunter
Date: Tue May 26 2020 - 11:29:45 EST


Reportedly, from 19.10 Ubuntu has begun mixing up the location of some
debug symbol files, putting files expected to be in
/usr/lib/debug/usr/lib into /usr/lib/debug/lib instead. Fix by adding
another dso_binary_type.

Example on Ubuntu 20.04

Before:

$ perf record -e intel_pt//u uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.030 MB perf.data ]
$ perf script --call-trace | head -5
uname 14003 [005] 15321.764958566: cbr: 42 freq: 4219 MHz (156%)
uname 14003 [005] 15321.764958566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) 7f1e71cc4100
uname 14003 [005] 15321.764961566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) 7f1e71cc4df0
uname 14003 [005] 15321.764961900: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) 7f1e71cc4e18
uname 14003 [005] 15321.764963233: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) 7f1e71cc5128

After:

$ perf script --call-trace | head -5
uname 14003 [005] 15321.764958566: cbr: 42 freq: 4219 MHz (156%)
uname 14003 [005] 15321.764958566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) _start
uname 14003 [005] 15321.764961566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) _dl_start
uname 14003 [005] 15321.764961900: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) _dl_start
uname 14003 [005] 15321.764963233: (/usr/lib/x86_64-linux-gnu/ld-2.31.so ) _dl_start

Reported-by: Travis Downs <travis.downs@xxxxxxxxx>
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
tools/perf/util/dso.c | 14 ++++++++++++++
tools/perf/util/dso.h | 1 +
tools/perf/util/probe-finder.c | 1 +
tools/perf/util/symbol.c | 2 ++
4 files changed, 18 insertions(+)

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index e68e1375e3c0..15b635d6c83c 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -47,6 +47,7 @@ char dso__symtab_origin(const struct dso *dso)
[DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO] = 'D',
[DSO_BINARY_TYPE__FEDORA_DEBUGINFO] = 'f',
[DSO_BINARY_TYPE__UBUNTU_DEBUGINFO] = 'u',
+ [DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO] = 'x',
[DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO] = 'o',
[DSO_BINARY_TYPE__BUILDID_DEBUGINFO] = 'b',
[DSO_BINARY_TYPE__SYSTEM_PATH_DSO] = 'd',
@@ -129,6 +130,19 @@ int dso__read_binary_type_filename(const struct dso *dso,
snprintf(filename + len, size - len, "%s", dso->long_name);
break;

+ case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
+ /*
+ * Ubuntu can mixup /usr/lib with /lib, putting debuginfo in
+ * /usr/lib/debug/lib when it is expected to be in
+ * /usr/lib/debug/usr/lib
+ */
+ if (strlen(dso->long_name) < 9 ||
+ strncmp(dso->long_name, "/usr/lib/", 9))
+ ret = -1;
+ len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
+ snprintf(filename + len, size - len, "%s", dso->long_name + 4);
+ break;
+
case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
{
const char *last_slash;
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index 42b3a278ac59..8b7958f02609 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -30,6 +30,7 @@ enum dso_binary_type {
DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
+ DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
DSO_BINARY_TYPE__GUEST_KMODULE,
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index e4cff49384f4..55924255c535 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -101,6 +101,7 @@ enum dso_binary_type distro_dwarf_types[] = {
DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
+ DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
DSO_BINARY_TYPE__NOT_FOUND,
};

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 7725c83996f4..44d81f90b604 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -79,6 +79,7 @@ static enum dso_binary_type binary_type_symtab[] = {
DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
+ DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
DSO_BINARY_TYPE__NOT_FOUND,
};

@@ -1529,6 +1530,7 @@ static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
+ case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
return !kmod && dso->kernel == DSO_TYPE_USER;
--
2.17.1