gdb/testsuite/gdb.trace/circ.exp

   1 # Copyright 1998-2018 Free Software Foundation, Inc.
   2
   3 # This program is free software; you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation; either version 3 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 load_lib "trace-support.exp"
  17
  18 standard_testfile
  19
  20 if {[prepare_for_testing "failed to prepare" $testfile $srcfile {debug nowarnings}]} {
  21     return -1
  22 }
  23
  24 # Tests:
  25 # 1) Calculate the size taken by one trace frame.
  26 # 2) Set up a trace experiment that will collect approximately 10 frames,
  27 #    requiring more than 512 but less than 1024 bytes of cache buffer.
  28 #    (most targets should have at least 1024 bytes of cache buffer!)
  29 #    Run and confirm that it collects all 10 frames.
  30 # 3) Artificially limit the trace buffer to 4x + a bytes.  Here x is the size
  31 #    of single trace frame and a is a small constant.  Rerun the
  32 #    experiment.  Confirm that the frame for the first tracepoint is collected,
  33 #    but frames for the last several tracepoints are not.
  34 # 4) Set trace buffer to circular mode, with the buffer size as in
  35 #    step 3 above.  Rerun the experiment.  Confirm that the frame for the last
  36 #    tracepoint is collected but not for the first one.
  37 #
  38
  39 # Set a tracepoint on given func.  The tracepoint is set at entry
  40 # address and not 'after prologue' address because we use
  41 # 'tfind pc func' to find the corresponding trace frame afterwards,
  42 # and that looks for entry address.
  43 proc set_a_tracepoint { func } {
  44     gdb_test "trace \*$func" "Tracepoint \[0-9\]+ at .*" \
  45         "set tracepoint at $func"
  46     gdb_trace_setactions "set actions for $func" "" "collect testload" "^$"
  47 }
  48
  49 # Sets the tracepoints from func0 to func9 using set_a_tracepoint.
  50 proc setup_tracepoints { } {
  51     gdb_delete_tracepoints
  52     set_a_tracepoint func0
  53     set_a_tracepoint func1
  54     set_a_tracepoint func2
  55     set_a_tracepoint func3
  56     set_a_tracepoint func4
  57     set_a_tracepoint func5
  58     set_a_tracepoint func6
  59     set_a_tracepoint func7
  60     set_a_tracepoint func8
  61     set_a_tracepoint func9
  62 }
  63
  64 # Start the trace, run to end and then stop the trace.
  65 proc run_trace_experiment { } {
  66     global decimal
  67
  68     setup_tracepoints
  69     gdb_test "break end" "Breakpoint $decimal.*" "breakpoint at end"
  70     gdb_test "tstart" "\[\r\n\]*" "start trace experiment"
  71     gdb_test "continue" "Continuing.*Breakpoint \[0-9\]+, end.*" \
  72         "run to end"
  73     gdb_test "tstop" "\[\r\n\]*" "stop trace experiment"
  74 }
  75
  76 if { ![runto_main] } {
  77     fail "can't run to main to check for trace support"
  78     return -1
  79 }
  80
  81 if { ![gdb_target_supports_trace] } {
  82     unsupported "target does not support trace"
  83     return 1
  84 }
  85
  86 set test "set circular-trace-buffer on"
  87 gdb_test_multiple "set circular-trace-buffer on" $test {
  88     -re ".*Target does not support this command.*$gdb_prompt $" {
  89         unsupported "target does not support circular trace buffer"
  90         return 1
  91     }
  92     -re "$gdb_prompt $" {
  93         pass $test
  94     }
  95 }
  96
  97 set circular_supported -1
  98 set test "check whether circular buffer is supported"
  99
 100 gdb_test_multiple "tstatus" $test {
 101     -re ".*Trace buffer is circular.*$gdb_prompt $" {
 102         set circular_supported 1
 103         pass $test
 104     }
 105     -re "$gdb_prompt $" {
 106         pass $test
 107     }
 108 }
 109
 110 if { $circular_supported < 0 } {
 111     unsupported "target does not support circular trace buffer"
 112     return 1
 113 }
 114
 115 gdb_test "show circular-trace-buffer" \
 116     "Target's use of circular trace buffer is on." \
 117     "show circular-trace-buffer (on)"
 118
 119 # Check if changing the trace buffer size is supported.  This step is
 120 # repeated twice.  This helps in case the trace buffer size is 100.
 121 set test_size 100
 122 set test "change buffer size to $test_size"
 123 gdb_test_multiple "set trace-buffer-size $test_size" $test {
 124     -re ".*Target does not support this command.*$gdb_prompt $" {
 125         unsupported "target does not support changing trace buffer size"
 126         return 1
 127     }
 128     -re "$gdb_prompt $" {
 129         pass $test
 130     }
 131 }
 132
 133 set test "check whether setting trace buffer size is supported"
 134 gdb_test_multiple "tstatus" $test {
 135     -re ".*Trace buffer has ($decimal) bytes of ($decimal) bytes free.*$gdb_prompt $" {
 136         set total_size $expect_out(2,string)
 137         if { $test_size != $total_size } {
 138             unsupported "target does not support changing trace buffer size"
 139             return 1
 140         }
 141         pass $test
 142     }
 143 }
 144
 145 set test_size 400
 146 gdb_test_no_output "set trace-buffer-size $test_size" \
 147     "change buffer size to $test_size"
 148
 149 gdb_test_multiple "tstatus" $test {
 150     -re ".*Trace buffer has ($decimal) bytes of ($decimal) bytes free.*$gdb_prompt $" {
 151         set total_size $expect_out(2,string)
 152         if { $test_size != $total_size } {
 153             unsupported "target does not support changing trace buffer size"
 154             return 1
 155         }
 156         pass $test
 157     }
 158 }
 159
 160 gdb_test_no_output "set circular-trace-buffer off" \
 161     "set circular-trace-buffer off"
 162
 163 gdb_test "show circular-trace-buffer" \
 164     "Target's use of circular trace buffer is off." \
 165     "show circular-trace-buffer (off)"
 166
 167 set total_size -1
 168 set free_size -1
 169 set frame_size -1
 170
 171 # Determine the size used by a single frame.  Set a single tracepoint,
 172 # run and then check the total and free size using the tstatus command.
 173 # Then subtracting free from total gives us the size of a frame.
 174 with_test_prefix "frame size" {
 175     set_a_tracepoint func0
 176
 177     gdb_test "break end" "Breakpoint $decimal.*" "breakpoint at end"
 178
 179     gdb_test "tstart" "\[\r\n\]*" "start trace"
 180
 181     gdb_test "continue" "Continuing.*Breakpoint \[0-9\]+, end.*" \
 182         "run to end"
 183
 184     gdb_test "tstop" "\[\r\n\]*" "stop trace"
 185
 186     set test "get buffer size"
 187
 188     gdb_test_multiple "tstatus" $test {
 189         -re ".*Trace buffer has ($decimal) bytes of ($decimal) bytes free.*$gdb_prompt $" {
 190             set free_size $expect_out(1,string)
 191             set total_size $expect_out(2,string)
 192             pass $test
 193         }
 194     }
 195
 196     # Check that we get the total_size and free_size.
 197     if { $total_size < 0 } {
 198         return 1
 199     }
 200
 201     if { $free_size < 0 } {
 202         return 1
 203     }
 204 }
 205
 206 # Calculate the size of a single frame.
 207 set frame_size "($total_size - $free_size)"
 208
 209 with_test_prefix "normal buffer" {
 210     clean_restart $testfile
 211
 212     if { ![runto_main] } {
 213         fail "can't run to main"
 214         return 1
 215     }
 216
 217     run_trace_experiment
 218
 219     # Check that the first frame is actually at func0.
 220     gdb_test "tfind start" ".*#0  func0 .*" \
 221         "first frame is at func0"
 222
 223     gdb_test "tfind pc func9" \
 224         ".*Found trace frame $decimal, tracepoint $decimal\r\n#0  func9 .*" \
 225         "find frame for func9"
 226 }
 227
 228 # Shrink the trace buffer so that it will not hold
 229 # all ten trace frames.  Verify that the frame for func0 is still
 230 # collected, but the frame for func9 is not.
 231
 232 set buffer_size "((4 * $frame_size) + 10)"
 233 with_test_prefix "small buffer" {
 234     clean_restart $testfile
 235
 236     if { ![runto_main] } {
 237         fail "can't run to main"
 238         return 1
 239     }
 240
 241     gdb_test_no_output "set trace-buffer-size $buffer_size" \
 242         "shrink the target trace buffer"
 243
 244     run_trace_experiment
 245
 246     gdb_test "tfind start" ".*#0  func0 .*" \
 247         "first frame is at func0"
 248
 249     gdb_test "tfind pc func9" ".* failed to find .*" \
 250         "find frame for func9"
 251 }
 252
 253 # Finally, make the buffer circular.  Now when it runs out of
 254 # space, it should wrap around and overwrite the earliest frames.
 255 # This means that:
 256 # 1) the first frame will be overwritten and therefore unavailable.
 257 # 2) the earliest frame in the buffer will not be for func0.
 258 # 3) the frame for func9 will be available (unlike "small buffer" case).
 259 with_test_prefix "circular buffer" {
 260     clean_restart $testfile
 261
 262     if { ![runto_main] } {
 263         fail "can't run to main"
 264         return 1
 265     }
 266
 267     gdb_test_no_output "set trace-buffer-size $buffer_size" \
 268         "shrink the target trace buffer"
 269
 270     gdb_test_no_output "set circular-trace-buffer on" \
 271         "make the target trace buffer circular"
 272
 273     run_trace_experiment
 274
 275     gdb_test "tstatus" \
 276         ".*Buffer contains $decimal trace frames \\(of $decimal created total\\).*Trace buffer is circular.*" \
 277         "trace buffer is circular"
 278
 279     # The first frame should not be at func0.
 280     gdb_test "tfind start" ".*#0  func\[1-9\] .*" \
 281         "first frame is NOT at func0"
 282
 283     gdb_test \
 284         "tfind pc func9" \
 285         ".*Found trace frame $decimal, tracepoint $decimal\r\n#0  func9 .*" \
 286         "find frame for func9"
 287 }