Omar Sandoval a5845e63d4 tests: fix race condition in stack trace tests ... Stephen Brennan reported a flaky test while working on #121: ====================================================================== ERROR: test_by_task_struct (tests.helpers.linux.test_stack_trace.TestStackTrace) ---------------------------------------------------------------------- Traceback (most recent call last): File "/home/runner/work/drgn/drgn/tests/helpers/linux/test_stack_trace.py", line 22, in test_by_task_struct self.assertIn("pause", str(self.prog.stack_trace(find_task(self.prog, pid)))) ValueError: cannot unwind stack of running task The problem is that the stack trace tests wait for the thread state to change to "S". However, the state is updated while the thread is still technically running. For example, the pause() system call is implemented as: SYSCALL_DEFINE0(pause) { while (!signal_pending(current)) { __set_current_state(TASK_INTERRUPTIBLE); schedule(); } return -ERESTARTNOHAND; } If Program.stack_trace() accesses the thread after the state is changed but before the thread has actually been scheduled out (namely, before task_struct::on_cpu is set to 0), it will fail. Instead, let's check /proc/$pid/syscall, which contains "running" until the thread is completely scheduled out. Signed-off-by: Omar Sandoval <osandov@osandov.com>		2021-11-04 14:13:55 -07:00
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helpers	tests: fix race condition in stack trace tests	2021-11-04 14:13:55 -07:00
__init__.py	Fix some flake8 errors	2021-08-11 14:52:44 -07:00
assembler.py	libdrgn: binary_buffer: handle non-canonical LEB128 numbers	2021-06-30 21:39:31 -07:00
dwarf.py	Track byte order in scalar types instead of objects	2021-02-19 21:41:29 -08:00
dwarfwriter.py	libdrgn: dwarf_index: handle DW_FORM_block	2021-06-30 01:34:52 -07:00
elf.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
elfwriter.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
libdrgn.py	Fix some flake8 errors	2021-08-11 14:52:44 -07:00
test_docs.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
test_dwarf.py	Fix some flake8 errors	2021-08-11 14:52:44 -07:00
test_language_c.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
test_lexer.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
test_object.py	Fix some flake8 errors	2021-08-11 14:52:44 -07:00
test_path.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
test_platform.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
test_program.py	tests: skip PID memory read test if /proc/$pid/mem doesn't work	2021-10-28 14:41:44 -07:00
test_python.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
test_serialize.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00
test_type.py	Fix some flake8 errors	2021-08-11 14:52:44 -07:00
test_util.py	Use GPL-3.0-or-later license identifier instead of GPL-3.0+	2021-04-03 01:10:35 -07:00