On Tue, Oct 26, 2021 at 5:43 AM Masami Hiramatsu mhiramat@kernel.org wrote:
Hi Kalesh,
On Mon, 25 Oct 2021 13:08:39 -0700 Kalesh Singh kaleshsingh@google.com wrote:
Add tests for the parsing of hist trigger expressions; and to validate expression evaluation.
Signed-off-by: Kalesh Singh kaleshsingh@google.com Reviewed-by: Namhyung Kim namhyung@kernel.org
Changes in v3:
- Remove .sym-offset error check tests
Changes in v2:
- Add Namhyung's Reviewed-by
- Update comment to clarify err_pos in "Too many subexpressions" test
.../testing/selftests/ftrace/test.d/functions | 4 +- .../trigger/trigger-hist-expressions.tc | 72 +++++++++++++++++++ 2 files changed, 74 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-expressions.tc
diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions index 000fd05e84b1..1855a63559ad 100644 --- a/tools/testing/selftests/ftrace/test.d/functions +++ b/tools/testing/selftests/ftrace/test.d/functions @@ -16,13 +16,13 @@ reset_tracer() { # reset the current tracer
reset_trigger_file() { # remove action triggers first
- grep -H ':on[^:]*(' $@ |
- grep -H ':on[^:]*(' $@ | tac | while read line; do cmd=`echo $line | cut -f2- -d: | cut -f1 -d"["` file=`echo $line | cut -f1 -d:` echo "!$cmd" >> $file done
- grep -Hv ^# $@ |
- grep -Hv ^# $@ | tac | while read line; do cmd=`echo $line | cut -f2- -d: | cut -f1 -d"["` file=`echo $line | cut -f1 -d:`
If this update has any meaning, please make a separate patch for this part.
Hi Masami,
Thanks for the feedback. The above change is to ensure we remove triggers in the reverse order that we created them - important when one trigger depends on another. I can split it out into a separate patch and will add a README pattern check to the requires tag for these tests.
Thanks, Kalesh
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-expressions.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-expressions.tc new file mode 100644 index 000000000000..e715641c54d3 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-expressions.tc @@ -0,0 +1,72 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: event trigger - test histogram expression parsing +# requires: set_event events/sched/sched_process_fork/trigger events/sched/sched_process_fork/hist error_log
Hmm, are there any way to check the running kernel supports this feature? Because the latest version of the kselftest is expected to run on the old stable kernel for testing, the testcase should check whether the kernel supports this testing feature or not. (That's why the requires tag supports README pattern check)
So, at first if you didn't update the <tracefs>/README, please update it first to show the new syntax is supported, and add "SOME-PATTERN":README to the requires tag.
Thank you,
+fail() { #msg
- echo $1
- exit_fail
+}
+get_hist_var() { #var_name hist_path
- hist_output=`grep -m1 "$1: " $2`
- hitcount=`echo $hist_output | awk '{ for (i=1; i<=NF; ++i) { if ($i ~ "hitcount:") print $(i+1)} }'`
- var_sum=`echo $hist_output | awk '{ for (i=1; i<=NF; ++i) { if ($i ~ "'$1':") print $(i+1)} }'`
- var_val=$(( var_sum / hitcount ))
- echo $var_val
+}
+test_hist_expr() { # test_name expression expected_val
- reset_trigger
- echo "Test hist trigger expressions - $1"
- echo "hist:keys=common_pid:x=$2" > events/sched/sched_process_fork/trigger
- echo 'hist:keys=common_pid:vals=$x' >> events/sched/sched_process_fork/trigger
- for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
- actual=`get_hist_var x events/sched/sched_process_fork/hist`
- if [ $actual != $3 ]; then
fail "Failed hist trigger expression evaluation: Expression: $2 Expected: $3, Actual: $actual"- fi
- reset_trigger
+}
+check_error() { # test_name command-with-error-pos-by-^
- reset_trigger
- echo "Test hist trigger expressions - $1"
- ftrace_errlog_check 'hist:sched:sched_process_fork' "$2" 'events/sched/sched_process_fork/trigger'
- reset_trigger
+}
+test_hist_expr "Variable assignment" "123" "123"
+test_hist_expr "Subtraction not associative" "16-8-4-2" "2"
+test_hist_expr "Division not associative" "64/8/4/2" "1"
+test_hist_expr "Same precedence operators (+,-) evaluated left to right" "16-8+4+2" "14"
+test_hist_expr "Same precedence operators (*,/) evaluated left to right" "4*3/2*2" "12"
+test_hist_expr "Multiplication evaluated before addition/subtraction" "4+3*2-2" "8"
+test_hist_expr "Division evaluated before addition/subtraction" "4+6/2-2" "5"
+# Division by zero returns -1 +test_hist_expr "Handles division by zero" "3/0" "-1"
+# err pos for "too many subexpressions" is dependent on where +# the last subexpression was detected. This can vary depending +# on how the expression tree was generated. +check_error "Too many subexpressions" 'hist:keys=common_pid:x=32+^10*3/20-4' +check_error "Too many subexpressions" 'hist:keys=common_pid:x=^1+2+3+4+5'
+check_error "Unary minus not supported in subexpression" 'hist:keys=common_pid:x=-(^1)+2'
+exit 0
2.33.0.1079.g6e70778dc9-goog
-- Masami Hiramatsu mhiramat@kernel.org