tests/regression/kernel/test_callstack

   1 #!/bin/bash
   2 #
   3 # Copyright (C) 2017 Francis Deslauriers <francis.deslauriers@efficios.com>
   4 #
   5 # SPDX-License-Identifier: GPL-2.0-only
   6 #
   7
   8 TEST_DESC="Kernel tracer - Callstack context"
   9
  10 CURDIR=$(dirname "$0")/
  11 TESTDIR=$CURDIR/../..
  12 NUM_TESTS=11
  13 TEST_APP_USERSPACE="$TESTDIR/utils/testapp/gen-syscall-events-callstack/gen-syscall-events-callstack"
  14 TEST_APP_KERNELSPACE="$TESTDIR/utils/testapp/gen-syscall-events/gen-syscall-events"
  15 PARSE_CALLSTACK="$TESTDIR/utils/parse-callstack.py"
  16
  17 SESSION_NAME="callstack"
  18 CHANNEL_NAME="chan0"
  19
  20 source "$TESTDIR/utils/utils.sh"
  21
  22 function lttng_untrack_all()
  23 {
  24         lttng_untrack 0 "-s $SESSION_NAME --all --pid -k"
  25 }
  26
  27 function lttng_track_pid()
  28 {
  29         local PID=$1
  30         lttng_track 0 "-s $SESSION_NAME -k --pid=$PID"
  31 }
  32
  33 function run_workload()
  34 {
  35         local TEST_APP=$1
  36         local start_file_sync
  37         start_file_sync=$(mktemp -u)
  38
  39         lttng_untrack_all
  40
  41         ./"$TEST_APP" "$start_file_sync" &
  42         PID=$!
  43         lttng_track_pid $PID
  44
  45         start_lttng_tracing_ok
  46
  47         # Create start file to launch the execution of the syscall call by the
  48         # test app.
  49         touch "$start_file_sync"
  50
  51         wait $PID
  52
  53         stop_lttng_tracing_ok
  54
  55         # Clean up the synchronization file.
  56         rm -f "$start_file_sync"
  57 }
  58
  59 function test_user_callstack()
  60 {
  61         TRACE_PATH=$(mktemp -d)
  62         # This is the expected userspace callstack. (see gen-syscall-events-callstack.c)
  63         USER_CS_EXPECTED="main fct_a fct_b fct_c my_gettid"
  64         EVENT_NAME="gettid"
  65
  66         diag "Userspace callstack test"
  67         create_lttng_session_ok $SESSION_NAME "$TRACE_PATH"
  68         lttng_enable_kernel_channel_ok "$SESSION_NAME" "$CHANNEL_NAME"
  69
  70         lttng_enable_kernel_syscall_ok "$SESSION_NAME" "$EVENT_NAME" "$CHANNEL_NAME"
  71         add_context_kernel_ok "$SESSION_NAME" "$CHANNEL_NAME" "callstack-user"
  72
  73         run_workload $TEST_APP_USERSPACE
  74
  75         destroy_lttng_session_ok "$SESSION_NAME"
  76
  77         "$BABELTRACE_BIN" "$TRACE_PATH" | grep $EVENT_NAME | ./"$PARSE_CALLSTACK" --user "$TEST_APP_USERSPACE" $USER_CS_EXPECTED
  78         ok $? "Validate userspace callstack"
  79
  80         rm -rf "$TRACE_PATH"
  81 }
  82
  83 function test_kernel_callstack()
  84 {
  85         TRACE_PATH=$(mktemp -d)
  86         # Those are symbol expected to be present in the kernel callstack. This
  87         # is not an exhaustive list since it's kernel dependent.
  88
  89         # FIXME: we used to test for the following symbols as well:
  90         # save_stack_trace, lttng_callstack_get_size, but they were removed
  91         # because:
  92         #       1. kernel commit 77072f09 make it so that save_stack_trace is
  93         #        omitted from the callstack itself, and
  94         #
  95         #       2. the code (of this commit) can trigger Tail Call Optimization
  96         #       which mess up with the stacktrace by omiting the wrong address
  97         #       from the stacktrace.
  98         # When this is fixed, we should add both save_stack_trace and
  99         # lttng_callstack_get_size symbols back in the list of expected
 100         # addresses.
 101         KERNEL_CS_EXPECTED="lttng_event_reserve"
 102         EVENT_NAME="read"
 103
 104         diag "Kernel callstack test"
 105         create_lttng_session_ok $SESSION_NAME "$TRACE_PATH"
 106         lttng_enable_kernel_channel_ok "$SESSION_NAME" "$CHANNEL_NAME"
 107
 108         lttng_enable_kernel_syscall_ok "$SESSION_NAME" "$EVENT_NAME" "$CHANNEL_NAME"
 109         add_context_kernel_ok "$SESSION_NAME" "$CHANNEL_NAME" "callstack-kernel"
 110
 111         run_workload $TEST_APP_KERNELSPACE
 112
 113         destroy_lttng_session_ok "$SESSION_NAME"
 114
 115         "$BABELTRACE_BIN" "$TRACE_PATH" | grep $EVENT_NAME | ./"$PARSE_CALLSTACK" --kernel $KERNEL_CS_EXPECTED
 116         ok $? "Validate kernel callstack"
 117
 118         rm -rf "$TRACE_PATH"
 119 }
 120
 121 # Only run userspace callstack test on x86
 122 uname -m | grep -E "x86" >/dev/null 2>&1
 123 if test $? == 0; then
 124         NUM_TESTS=$((NUM_TESTS+11))
 125         RUN_USERSPACE_TEST=1
 126 else
 127         RUN_USERSPACE_TEST=0
 128 fi
 129
 130 # MUST set TESTDIR before calling those functions
 131 plan_tests $NUM_TESTS
 132
 133 print_test_banner "$TEST_DESC"
 134
 135 if [ "$(id -u)" == "0" ]; then
 136         isroot=1
 137 else
 138         isroot=0
 139 fi
 140
 141 skip $isroot "Root access is needed. Skipping all tests." "$NUM_TESTS" ||
 142 {
 143         which "$BABELTRACE_BIN" > /dev/null
 144         test $? -ne 0
 145         skip $? "Babeltrace binary not found. Skipping callstack tests" "$NUM_TESTS" ||
 146         {
 147                 start_lttng_sessiond
 148
 149                 if test $RUN_USERSPACE_TEST == 1; then
 150                         test_user_callstack
 151                 fi
 152
 153                 test_kernel_callstack
 154
 155                 stop_lttng_sessiond
 156         }
 157 }