From 16dd99389198f584be2393d1dc5e049b4ac1f8d5 Mon Sep 17 00:00:00 2001 From: =?utf8?q?J=C3=A9r=C3=A9mie=20Galarneau?= Date: Thu, 25 May 2023 19:15:20 -0400 Subject: [PATCH] Tests fix: test_callstack: output of addr2line incorrectly parsed MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Issue observed -------------- The test_callstack test fails with GCC 13.1 with the following output: Traceback (most recent call last): File "/usr/lib/lttng-tools/ptest/tests/regression/././kernel//../../utils/parse-callstack.py", line 160, in main() File "/usr/lib/lttng-tools/ptest/tests/regression/././kernel//../../utils/parse-callstack.py", line 155, in main raise Exception('Expected function name not found in recorded callstack') Exception: Expected function name not found in recorded callstack ok 10 - Destroy session callstack PASS: kernel/test_callstack 10 - Destroy session callstack not ok 11 - Validate userspace callstack FAIL: kernel/test_callstack 11 - Validate userspace callstack Cause ----- parse-callstack.py uses 'split()' to split the lines of addr2line's output. By default, 'split()' splits a string on any whitespace. Typically this was fine as addr2line's output doesn't contain spaces and the function then splits on new lines. Typical output of addr2line: $ addr2line -e ./tests/regression/kernel//../../utils/testapp/gen-syscall-events-callstack/gen-syscall-events-callstack --functions --addresses 0x40124B 0x000000000040124b my_gettid /tmp/test-callstack-master/src/lttng-tools/tests/utils/testapp/gen-syscall-events-callstack/gen-syscall-events-callstack.c:40 However, with the test app compiled using gcc 13.1, a "discriminator" annotation is present: 0x0000000000401279 fct_b /tmp/test-callstack-master/src/lttng-tools/tests/utils/testapp/gen-syscall-events-callstack/gen-syscall-events-callstack.c:58 (discriminator 1) Hence, by selecting the second to last element (-2, with negative indexing), the addr2line function returns '(discriminator' as the function name. Solution -------- The parsing code is changed to simply iterate on groups of 3 lines, following addr2line's output format. Fixes #1377 Change-Id: I8c1eab97e84ca7cad171904bed6660540061cf08 Signed-off-by: Jérémie Galarneau --- tests/utils/parse-callstack.py | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/tests/utils/parse-callstack.py b/tests/utils/parse-callstack.py index c3f0e2e9b..029100b61 100755 --- a/tests/utils/parse-callstack.py +++ b/tests/utils/parse-callstack.py @@ -26,14 +26,23 @@ def addr2line(executable, addr): status = subprocess.run(cmd, stdout=subprocess.PIPE, check=True) - addr2line_output = status.stdout.decode("utf-8") - - # Omit the last 2 lines as the caller of main can not be determine - fcts = [addr2line_output.split()[-2]] - - fcts = [ f for f in fcts if '??' not in f] - - return fcts + addr2line_output = status.stdout.decode("utf-8").splitlines() + # addr2line's output is made of 3-tuples: + # - address + # - function name + # - source location + if len(addr2line_output) % 3 != 0: + raise Exception('Unexpected addr2line output:\n\t{}'.format('\n\t'.join(addr2line_output))) + + function_names = [] + for address_line_number in range(0, len(addr2line_output), 3): + function_name = addr2line_output[address_line_number + 1] + + # Filter-out unresolved functions + if "??" not in function_name: + function_names.append(addr2line_output[address_line_number + 1]) + + return function_names def extract_user_func_names(executable, raw_callstack): """ -- 2.34.1