Thread (8 messages) 8 messages, 2 authors, 2024-12-27

Re: [PATCH] tools/perf/tests/base_probe: Fix check for the count of existing probes in test_adding_kernel

From: Michael Petlan <hidden>
Date: 2024-10-17 11:03:56
Also in: linux-perf-users

On Mon, 14 Oct 2024, Athira Rajeev wrote:
perftool-testsuite_probe fails in test_adding_kernel as below:
	Regexp not found: "probe:inode_permission_11"
	-- [ FAIL ] -- perf_probe :: test_adding_kernel :: force-adding probes ::
	second probe adding (with force) (output regexp parsing)
	event syntax error: 'probe:inode_permission_11'
	  \___ unknown tracepoint

	Error:  File /sys/kernel/tracing//events/probe/inode_permission_11
	not found.
	Hint:   Perhaps this kernel misses some CONFIG_ setting to
	enable this feature?.

The test does the following:
1) Adds a probe point first using :
    $CMD_PERF probe --add $TEST_PROBE
2) Then tries to add same probe again without —force
and expects it to fail. Next tries to add same probe again
with —force. In this case, perf probe succeeds and adds
the probe with a suffix number. Example:

 ./perf probe --add inode_permission
 Added new event:
  probe:inode_permission (on inode_permission)

 ./perf probe --add inode_permission --force
 Added new event:
  probe:inode_permission_1 (on inode_permission)

  ./perf probe --add inode_permission --force
 Added new event:
  probe:inode_permission_2 (on inode_permission)

Each time, suffix is added to existing probe name.
To get the suffix number, test cases uses :
NO_OF_PROBES=`$CMD_PERF probe -l | wc -l`

This will work if there is no other probe existing
in the system. If there are any other probes other than
kernel probes or inode_permission, ( example: any probe),
"perf probe -l" will include count for other probes too.
Hello.

When designing this test, I was relying on the fact that
there are no existing probes, because all should have been
removed at line 43 of the same test:

	40 ### basic probe adding
	41
	42 for opt in "" "-a" "--add"; do
-->	43 	   clear_all_probes
	44 	   $CMD_PERF probe $opt $TEST_PROBE 2> $LOGS_DIR/adding_kernel_add$opt.err
	45 	   PERF_EXIT_CODE=$?
	46
	47	../common/check_all_patterns_found.pl "Added new events?:" "probe:$TEST_PROBE" "on $TEST_PROBE" < $LOGS_DIR/adding_kernel_add$opt.err
	48 	CHECK_EXIT_CODE=$?
	49
	50	print_results $PERF_EXIT_CODE $CHECK_EXIT_CODE "adding probe $TEST_PROBE :: $opt"
	51 	(( TEST_RESULT += $? ))
	52 done
	53

I am wondering how it could happen that there were other
probes in the system?

Cheers,

Michael
quoted hunk ↗ jump to hunk
Example, in the system where this failed, already some
probes were default added. So count became 10
  ./perf probe -l | wc -l
  10

So to be specific for "inode_permission", restrict the
probe count check to that probe point alone using :
NO_OF_PROBES=`$CMD_PERF probe -l $TEST_PROBE| wc -l`

Similarly while removing the probe using "probe --del *",
( removing all probes ), check uses:

 ../common/check_all_lines_matched.pl "Removed event: probe:$TEST_PROBE"

But if there are other probes in the system, the log will
contain reference to other existing probe too. Hence change
usage of check_all_lines_matched.pl to check_all_patterns_found.pl
This will make sure expecting string comes in the result

Signed-off-by: Athira Rajeev <redacted>
---
 tools/perf/tests/shell/base_probe/test_adding_kernel.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/perf/tests/shell/base_probe/test_adding_kernel.sh b/tools/perf/tests/shell/base_probe/test_adding_kernel.sh
index d541ffd44a93..f8b5f096d0d7 100755
--- a/tools/perf/tests/shell/base_probe/test_adding_kernel.sh
+++ b/tools/perf/tests/shell/base_probe/test_adding_kernel.sh
@@ -169,7 +169,7 @@ print_results $PERF_EXIT_CODE $CHECK_EXIT_CODE "force-adding probes :: second pr
 (( TEST_RESULT += $? ))
 
 # adding existing probe with '--force' should pass
-NO_OF_PROBES=`$CMD_PERF probe -l | wc -l`
+NO_OF_PROBES=`$CMD_PERF probe -l $TEST_PROBE| wc -l`
 $CMD_PERF probe --force --add $TEST_PROBE 2> $LOGS_DIR/adding_kernel_forceadd_03.err
 PERF_EXIT_CODE=$?
 
@@ -205,7 +205,7 @@ print_results $PERF_EXIT_CODE $CHECK_EXIT_CODE "using doubled probe"
 $CMD_PERF probe --del \* 2> $LOGS_DIR/adding_kernel_removing_wildcard.err
 PERF_EXIT_CODE=$?
 
-../common/check_all_lines_matched.pl "Removed event: probe:$TEST_PROBE" "Removed event: probe:${TEST_PROBE}_1" < $LOGS_DIR/adding_kernel_removing_wildcard.err
+../common/check_all_patterns_found.pl "Removed event: probe:$TEST_PROBE" "Removed event: probe:${TEST_PROBE}_1" < $LOGS_DIR/adding_kernel_removing_wildcard.err
 CHECK_EXIT_CODE=$?
 
 print_results $PERF_EXIT_CODE $CHECK_EXIT_CODE "removing multiple probes"
-- 
2.43.5

Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help