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=$1
  36         # shift the first argument, passing along the other args if any to the
  37         # test app.
  38         shift
  39         local start_file_sync
  40         start_file_sync=$(mktemp -u)
  41
  42         lttng_untrack_all
  43
  44         ./"$TEST_APP" "$start_file_sync" "$@" &
  45         PID=$!
  46         lttng_track_pid $PID
  47
  48         start_lttng_tracing_ok
  49
  50         # Create start file to launch the execution of the syscall call by the
  51         # test app.
  52         touch "$start_file_sync"
  53
  54         wait $PID
  55
  56         stop_lttng_tracing_ok
  57
  58         # Clean up the synchronization file.
  59         rm -f "$start_file_sync"
  60 }
  61
  62 function test_user_callstack()
  63 {
  64         TRACE_PATH=$(mktemp -d)
  65         # This is the expected userspace callstack. (see gen-syscall-events-callstack.c)
  66         USER_CS_EXPECTED="main fct_a fct_b fct_c my_gettid"
  67         EVENT_NAME="gettid"
  68
  69         diag "Userspace callstack test"
  70         create_lttng_session_ok $SESSION_NAME "$TRACE_PATH"
  71         lttng_enable_kernel_channel_ok "$SESSION_NAME" "$CHANNEL_NAME"
  72
  73         lttng_enable_kernel_syscall_ok "$SESSION_NAME" "$EVENT_NAME" "$CHANNEL_NAME"
  74         add_context_kernel_ok "$SESSION_NAME" "$CHANNEL_NAME" "callstack-user"
  75
  76         run_workload $TEST_APP_USERSPACE
  77
  78         destroy_lttng_session_ok "$SESSION_NAME"
  79
  80         "$BABELTRACE_BIN" "$TRACE_PATH" | grep $EVENT_NAME | ./"$PARSE_CALLSTACK" --user "$TEST_APP_USERSPACE" $USER_CS_EXPECTED
  81         ok $? "Validate userspace callstack"
  82
  83         rm -rf "$TRACE_PATH"
  84 }
  85
  86 function test_kernel_callstack()
  87 {
  88         TRACE_PATH=$(mktemp -d)
  89         # Those are symbol expected to be present in the kernel callstack. This
  90         # is not an exhaustive list since it's kernel dependent.
  91
  92         # FIXME: we used to test for the following symbols as well:
  93         # save_stack_trace, lttng_callstack_get_size, but they were removed
  94         # because:
  95         #       1. kernel commit 77072f09 make it so that save_stack_trace is
  96         #        omitted from the callstack itself, and
  97         #
  98         #       2. the code (of this commit) can trigger Tail Call Optimization
  99         #       which mess up with the stacktrace by omiting the wrong address
 100         #       from the stacktrace.
 101         # When this is fixed, we should add both save_stack_trace and
 102         # lttng_callstack_get_size symbols back in the list of expected
 103         # addresses.
 104         KERNEL_CS_EXPECTED="lttng_event_reserve"
 105         EVENT_NAME="read"
 106
 107         diag "Kernel callstack test"
 108         create_lttng_session_ok $SESSION_NAME "$TRACE_PATH"
 109         lttng_enable_kernel_channel_ok "$SESSION_NAME" "$CHANNEL_NAME"
 110
 111         lttng_enable_kernel_syscall_ok "$SESSION_NAME" "$EVENT_NAME" "$CHANNEL_NAME"
 112         add_context_kernel_ok "$SESSION_NAME" "$CHANNEL_NAME" "callstack-kernel"
 113
 114         run_workload "$TEST_APP_KERNELSPACE" "/proc/cpuinfo" "/proc/cmdline"
 115
 116         destroy_lttng_session_ok "$SESSION_NAME"
 117
 118         "$BABELTRACE_BIN" "$TRACE_PATH" | grep $EVENT_NAME | ./"$PARSE_CALLSTACK" --kernel $KERNEL_CS_EXPECTED
 119         ok $? "Validate kernel callstack"
 120
 121         rm -rf "$TRACE_PATH"
 122 }
 123
 124 # Only run userspace callstack test on x86
 125 uname -m | grep -E "x86" >/dev/null 2>&1
 126 if test $? == 0; then
 127         NUM_TESTS=$((NUM_TESTS+11))
 128         RUN_USERSPACE_TEST=1
 129 else
 130         RUN_USERSPACE_TEST=0
 131 fi
 132
 133 # MUST set TESTDIR before calling those functions
 134 plan_tests $NUM_TESTS
 135
 136 print_test_banner "$TEST_DESC"
 137
 138 if [ "$(id -u)" == "0" ]; then
 139         isroot=1
 140 else
 141         isroot=0
 142 fi
 143
 144 skip $isroot "Root access is needed. Skipping all tests." "$NUM_TESTS" ||
 145 {
 146         which "$BABELTRACE_BIN" > /dev/null
 147         test $? -ne 0
 148         skip $? "Babeltrace binary not found. Skipping callstack tests" "$NUM_TESTS" ||
 149         {
 150                 start_lttng_sessiond
 151
 152                 if test $RUN_USERSPACE_TEST == 1; then
 153                         test_user_callstack
 154                 fi
 155
 156                 test_kernel_callstack
 157
 158                 stop_lttng_sessiond
 159         }
 160 }