xref: /llvm-project/lldb/test/API/functionalities/thread/num_threads/TestNumThreads.py (revision 9c2468821ec51defd09c246fea4a47886fff8c01) 
1"""
2Test number of threads.
3"""
4
5
6import lldb
7from lldbsuite.test.decorators import *
8from lldbsuite.test.lldbtest import *
9import lldbsuite.test.lldbutil as lldbutil
10
11
12class NumberOfThreadsTestCase(TestBase):
13    NO_DEBUG_INFO_TESTCASE = True
14
15    def setUp(self):
16        # Call super's setUp().
17        TestBase.setUp(self)
18        # Find the line numbers for our break points.
19        self.thread3_notify_all_line = line_number(
20            "main.cpp", "// Set thread3 break point on notify_all at this line."
21        )
22        self.thread3_before_lock_line = line_number(
23            "main.cpp", "// thread3-before-lock"
24        )
25
26    def test_number_of_threads(self):
27        """Test number of threads."""
28        self.build()
29        exe = self.getBuildArtifact("a.out")
30        self.runCmd("file " + exe, CURRENT_EXECUTABLE_SET)
31
32        # This should create a breakpoint with 1 location.
33        lldbutil.run_break_set_by_file_and_line(
34            self, "main.cpp", self.thread3_notify_all_line, num_expected_locations=1
35        )
36
37        # The breakpoint list should show 1 location.
38        self.expect(
39            "breakpoint list -f",
40            "Breakpoint location shown correctly",
41            substrs=[
42                "1: file = 'main.cpp', line = %d, exact_match = 0, locations = 1"
43                % self.thread3_notify_all_line
44            ],
45        )
46
47        # Run the program.
48        self.runCmd("run", RUN_SUCCEEDED)
49
50        # Stopped once.
51        self.expect(
52            "thread list",
53            STOPPED_DUE_TO_BREAKPOINT,
54            substrs=["stop reason = breakpoint 1."],
55        )
56
57        # Get the target process
58        target = self.dbg.GetSelectedTarget()
59        process = target.GetProcess()
60
61        # Get the number of threads
62        num_threads = process.GetNumThreads()
63
64        # Using std::thread may involve extra threads, so we assert that there are
65        # at least 4 rather than exactly 4.
66        self.assertGreaterEqual(
67            num_threads,
68            13,
69            "Number of expected threads and actual threads do not match.",
70        )
71
72    @skipIfDarwin  # rdar://33462362
73    @skipIfWindows  # This is flakey on Windows: llvm.org/pr37658, llvm.org/pr38373
74    def test_unique_stacks(self):
75        """Test backtrace unique with multiple threads executing the same stack."""
76        self.build()
77        exe = self.getBuildArtifact("a.out")
78        self.runCmd("file " + exe, CURRENT_EXECUTABLE_SET)
79
80        # Set a break point on the thread3 notify all (should get hit on threads 4-13).
81        lldbutil.run_break_set_by_file_and_line(
82            self, "main.cpp", self.thread3_before_lock_line, num_expected_locations=1
83        )
84
85        # Run the program.
86        self.runCmd("run", RUN_SUCCEEDED)
87
88        # Stopped once.
89        self.expect(
90            "thread list",
91            STOPPED_DUE_TO_BREAKPOINT,
92            substrs=["stop reason = breakpoint 1."],
93        )
94
95        process = self.process()
96
97        # Get the number of threads
98        num_threads = process.GetNumThreads()
99
100        # Using std::thread may involve extra threads, so we assert that there are
101        # at least 10 thread3's rather than exactly 10.
102        self.assertGreaterEqual(
103            num_threads,
104            10,
105            "Number of expected threads and actual threads do not match.",
106        )
107
108        # Attempt to walk each of the thread's executing the thread3 function to
109        # the same breakpoint.
110        def is_thread3(thread):
111            for frame in thread:
112                if frame.GetFunctionName() is None:
113                    continue
114                if "thread3" in frame.GetFunctionName():
115                    return True
116            return False
117
118        expect_threads = ""
119        for i in range(num_threads):
120            thread = process.GetThreadAtIndex(i)
121            self.assertTrue(thread.IsValid())
122            if not is_thread3(thread):
123                continue
124
125            # If we aren't stopped out the thread breakpoint try to resume.
126            if thread.GetStopReason() != lldb.eStopReasonBreakpoint:
127                self.runCmd("thread continue %d" % (i + 1))
128            self.assertStopReason(thread.GetStopReason(), lldb.eStopReasonBreakpoint)
129
130            expect_threads += " #%d" % (i + 1)
131
132        # Construct our expected back trace string
133        expect_string = "10 thread(s)%s" % (expect_threads)
134
135        # Now that we are stopped, we should have 10 threads waiting in the
136        # thread3 function. All of these threads should show as one stack.
137        self.expect(
138            "thread backtrace unique",
139            "Backtrace with unique stack shown correctly",
140            substrs=[expect_string, "main.cpp:%d" % self.thread3_before_lock_line],
141        )
142