354 lines · python
1"""2A stress-test of sorts for LLDB's handling of threads in the inferior.3 4This test sets a breakpoint in the main thread where test parameters (numbers of5threads) can be adjusted, runs the inferior to that point, and modifies the6locals that control the event thread counts. This test also sets a breakpoint in7breakpoint_func (the function executed by each 'breakpoint' thread) and a8watchpoint on a global modified in watchpoint_func. The inferior is continued9until exit or a crash takes place, and the number of events seen by LLDB is10verified to match the expected number of events.11"""12 13 14import lldb15from lldbsuite.test.decorators import *16from lldbsuite.test.lldbtest import *17from lldbsuite.test import lldbutil18 19 20class ConcurrentEventsBase(TestBase):21 # Concurrency is the primary test factor here, not debug info variants.22 NO_DEBUG_INFO_TESTCASE = True23 24 def setUp(self):25 # Call super's setUp().26 super(ConcurrentEventsBase, self).setUp()27 # Find the line number for our breakpoint.28 self.filename = "main.cpp"29 self.thread_breakpoint_line = line_number(30 self.filename, "// Set breakpoint here"31 )32 self.setup_breakpoint_line = line_number(33 self.filename, "// Break here and adjust num"34 )35 self.finish_breakpoint_line = line_number(36 self.filename, "// Break here and verify one thread is active"37 )38 39 def describe_threads(self):40 ret = []41 for x in self.inferior_process:42 id = x.GetIndexID()43 reason = x.GetStopReason()44 status = "stopped" if x.IsStopped() else "running"45 reason_str = lldbutil.stop_reason_to_str(reason)46 if reason == lldb.eStopReasonBreakpoint:47 bpid = x.GetStopReasonDataAtIndex(0)48 bp = self.inferior_target.FindBreakpointByID(bpid)49 reason_str = "%s hit %d times" % (50 lldbutil.get_description(bp),51 bp.GetHitCount(),52 )53 elif reason == lldb.eStopReasonWatchpoint:54 watchid = x.GetStopReasonDataAtIndex(0)55 watch = self.inferior_target.FindWatchpointByID(watchid)56 reason_str = "%s hit %d times" % (57 lldbutil.get_description(watch),58 watch.GetHitCount(),59 )60 elif reason == lldb.eStopReasonSignal:61 signals = self.inferior_process.GetUnixSignals()62 signal_name = signals.GetSignalAsCString(x.GetStopReasonDataAtIndex(0))63 reason_str = "signal %s" % signal_name64 65 location = "\t".join(66 [67 lldbutil.get_description(x.GetFrameAtIndex(i))68 for i in range(x.GetNumFrames())69 ]70 )71 ret.append(72 "thread %d %s due to %s at\n\t%s" % (id, status, reason_str, location)73 )74 return ret75 76 def add_breakpoint(self, line, descriptions):77 """Adds a breakpoint at self.filename:line and appends its description to descriptions, and78 returns the LLDB SBBreakpoint object.79 """80 81 bpno = lldbutil.run_break_set_by_file_and_line(82 self, self.filename, line, num_expected_locations=-183 )84 bp = self.inferior_target.FindBreakpointByID(bpno)85 descriptions.append(": file = 'main.cpp', line = %d" % line)86 return bp87 88 def inferior_done(self):89 """Returns true if the inferior is done executing all the event threads (and is stopped at self.finish_breakpoint,90 or has terminated execution.91 """92 return (93 self.finish_breakpoint.GetHitCount() > 094 or self.crash_count > 095 or self.inferior_process.GetState() == lldb.eStateExited96 )97 98 def count_signaled_threads(self):99 count = 0100 for thread in self.inferior_process:101 if (102 thread.GetStopReason() == lldb.eStopReasonSignal103 and thread.GetStopReasonDataAtIndex(0)104 == self.inferior_process.GetUnixSignals().GetSignalNumberFromName(105 "SIGUSR1"106 )107 ):108 count += 1109 return count110 111 def do_thread_actions(112 self,113 num_breakpoint_threads=0,114 num_signal_threads=0,115 num_watchpoint_threads=0,116 num_crash_threads=0,117 num_delay_breakpoint_threads=0,118 num_delay_signal_threads=0,119 num_delay_watchpoint_threads=0,120 num_delay_crash_threads=0,121 ):122 """Sets a breakpoint in the main thread where test parameters (numbers of threads) can be adjusted, runs the inferior123 to that point, and modifies the locals that control the event thread counts. Also sets a breakpoint in124 breakpoint_func (the function executed by each 'breakpoint' thread) and a watchpoint on a global modified in125 watchpoint_func. The inferior is continued until exit or a crash takes place, and the number of events seen by LLDB126 is verified to match the expected number of events.127 """128 exe = self.getBuildArtifact("a.out")129 self.runCmd("file " + exe, CURRENT_EXECUTABLE_SET)130 131 # Get the target132 self.inferior_target = self.dbg.GetSelectedTarget()133 134 expected_bps = []135 136 # Initialize all the breakpoints (main thread/aux thread)137 self.setup_breakpoint = self.add_breakpoint(138 self.setup_breakpoint_line, expected_bps139 )140 self.finish_breakpoint = self.add_breakpoint(141 self.finish_breakpoint_line, expected_bps142 )143 144 # Set the thread breakpoint145 if num_breakpoint_threads + num_delay_breakpoint_threads > 0:146 self.thread_breakpoint = self.add_breakpoint(147 self.thread_breakpoint_line, expected_bps148 )149 150 # Verify breakpoints151 self.expect(152 "breakpoint list -f",153 "Breakpoint locations shown correctly",154 substrs=expected_bps,155 )156 157 # Run the program.158 self.runCmd("run", RUN_SUCCEEDED)159 160 # Check we are at line self.setup_breakpoint161 self.expect(162 "thread backtrace",163 STOPPED_DUE_TO_BREAKPOINT,164 substrs=["stop reason = breakpoint 1."],165 )166 167 # Initialize the (single) watchpoint on the global variable (g_watchme)168 if num_watchpoint_threads + num_delay_watchpoint_threads > 0:169 # The concurrent tests have multiple threads modifying a variable170 # with the same value. The default "modify" style watchpoint will171 # only report this as 1 hit for all threads, because they all wrote172 # the same value. The testsuite needs "write" style watchpoints to173 # get the correct number of hits reported.174 self.runCmd("watchpoint set variable -w write g_watchme")175 for w in self.inferior_target.watchpoint_iter():176 self.thread_watchpoint = w177 self.assertTrue(178 "g_watchme" in str(self.thread_watchpoint),179 "Watchpoint location not shown correctly",180 )181 182 # Get the process183 self.inferior_process = self.inferior_target.GetProcess()184 185 # We should be stopped at the setup site where we can set the number of186 # threads doing each action (break/crash/signal/watch)187 self.assertEqual(188 self.inferior_process.GetNumThreads(),189 1,190 "Expected to stop before any additional threads are spawned.",191 )192 193 self.runCmd("expr num_breakpoint_threads=%d" % num_breakpoint_threads)194 self.runCmd("expr num_crash_threads=%d" % num_crash_threads)195 self.runCmd("expr num_signal_threads=%d" % num_signal_threads)196 self.runCmd("expr num_watchpoint_threads=%d" % num_watchpoint_threads)197 198 self.runCmd(199 "expr num_delay_breakpoint_threads=%d" % num_delay_breakpoint_threads200 )201 self.runCmd("expr num_delay_crash_threads=%d" % num_delay_crash_threads)202 self.runCmd("expr num_delay_signal_threads=%d" % num_delay_signal_threads)203 self.runCmd(204 "expr num_delay_watchpoint_threads=%d" % num_delay_watchpoint_threads205 )206 207 # Continue the inferior so threads are spawned208 self.runCmd("continue")209 210 # Make sure we see all the threads. The inferior program's threads all synchronize with a pseudo-barrier; that is,211 # the inferior program ensures all threads are started and running212 # before any thread triggers its 'event'.213 num_threads = self.inferior_process.GetNumThreads()214 expected_num_threads = (215 num_breakpoint_threads216 + num_delay_breakpoint_threads217 + num_signal_threads218 + num_delay_signal_threads219 + num_watchpoint_threads220 + num_delay_watchpoint_threads221 + num_crash_threads222 + num_delay_crash_threads223 + 1224 )225 self.assertEqual(226 num_threads,227 expected_num_threads,228 "Expected to see %d threads, but seeing %d. Details:\n%s"229 % (expected_num_threads, num_threads, "\n\t".join(self.describe_threads())),230 )231 232 self.signal_count = self.count_signaled_threads()233 self.crash_count = len(234 lldbutil.get_crashed_threads(self, self.inferior_process)235 )236 237 # Run to completion (or crash)238 while not self.inferior_done():239 if self.TraceOn():240 self.runCmd("thread backtrace all")241 self.runCmd("continue")242 self.signal_count += self.count_signaled_threads()243 self.crash_count += len(244 lldbutil.get_crashed_threads(self, self.inferior_process)245 )246 247 if num_crash_threads > 0 or num_delay_crash_threads > 0:248 # Expecting a crash249 self.assertTrue(250 self.crash_count > 0,251 "Expecting at least one thread to crash. Details: %s"252 % "\t\n".join(self.describe_threads()),253 )254 255 # Ensure the zombie process is reaped256 self.runCmd("process kill")257 258 elif num_crash_threads == 0 and num_delay_crash_threads == 0:259 # There should be a single active thread (the main one) which hit260 # the breakpoint after joining261 self.assertEqual(262 1,263 self.finish_breakpoint.GetHitCount(),264 "Expected main thread (finish) breakpoint to be hit once",265 )266 267 # There should be a single active thread (the main one) which hit268 # the breakpoint after joining. Depending on the pthread269 # implementation we may have a worker thread finishing the pthread_join()270 # after it has returned. Filter the threads to only count those271 # with user functions on them from our test case file,272 # lldb/test/API/functionalities/thread/concurrent_events/main.cpp273 user_code_funcnames = [274 "breakpoint_func",275 "crash_func",276 "do_action_args",277 "dotest",278 "main",279 "register_signal_handler",280 "signal_func",281 "sigusr1_handler",282 "start_threads",283 "watchpoint_func",284 ]285 num_threads_with_usercode = 0286 for t in self.inferior_process.threads:287 thread_has_user_code = False288 for f in t.frames:289 for funcname in user_code_funcnames:290 if funcname in f.GetDisplayFunctionName():291 thread_has_user_code = True292 break293 294 if thread_has_user_code:295 break296 297 if thread_has_user_code:298 num_threads_with_usercode += 1299 300 self.assertEqual(301 1,302 num_threads_with_usercode,303 "Expecting 1 thread but seeing %d. Details:%s"304 % (num_threads_with_usercode, "\n\t".join(self.describe_threads())),305 )306 self.runCmd("continue")307 308 # The inferior process should have exited without crashing309 self.assertEqual(310 0, self.crash_count, "Unexpected thread(s) in crashed state"311 )312 self.assertEqual(313 self.inferior_process.GetState(), lldb.eStateExited, PROCESS_EXITED314 )315 316 # Verify the number of actions took place matches expected numbers317 expected_breakpoint_threads = (318 num_delay_breakpoint_threads + num_breakpoint_threads319 )320 breakpoint_hit_count = (321 self.thread_breakpoint.GetHitCount()322 if expected_breakpoint_threads > 0323 else 0324 )325 self.assertEqual(326 expected_breakpoint_threads,327 breakpoint_hit_count,328 "Expected %d breakpoint hits, but got %d"329 % (expected_breakpoint_threads, breakpoint_hit_count),330 )331 332 expected_signal_threads = num_delay_signal_threads + num_signal_threads333 self.assertEqual(334 expected_signal_threads,335 self.signal_count,336 "Expected %d stops due to signal delivery, but got %d"337 % (expected_signal_threads, self.signal_count),338 )339 340 expected_watchpoint_threads = (341 num_delay_watchpoint_threads + num_watchpoint_threads342 )343 watchpoint_hit_count = (344 self.thread_watchpoint.GetHitCount()345 if expected_watchpoint_threads > 0346 else 0347 )348 self.assertEqual(349 expected_watchpoint_threads,350 watchpoint_hit_count,351 "Expected %d watchpoint hits, got %d"352 % (expected_watchpoint_threads, watchpoint_hit_count),353 )354