Merge tag 'probes-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull probes updates from Masami Hiramatsu:

 - probe-events: Add comments about entry data storing code to clarify
   where and how the entry data is stored for function return events.

 - probe-events: Log error for exceeding the number of arguments to help
   user to identify error reason via tracefs/error_log file.

 - Improve the ftracetest selftests:
    - Expand the tprobe event test to check if it can correctly find the
      wrong format tracepoint name.
    - Add new syntax error test to check whether error_log correctly
      indicates a wrong character in the tracepoint name.
    - Add a new dynamic events argument limitation test case which
      checks max number of probe arguments.

* tag 'probes-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: probe-events: Add comments about entry data storing code
  selftests/ftrace: Add dynamic events argument limitation test case
  selftests/ftrace: Add new syntax error test
  selftests/ftrace: Expand the tprobe event test to check wrong format
  tracing: probe-events: Log error for exceeding the number of arguments

3 files changed, 57 insertions, 0 deletions

diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc
index 155792eaeee5..f271c4238b72 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc
@@ -6,6 +6,7 @@
 echo 0 > events/enable
 echo > dynamic_events
 
+SUBSYSTEM=kmem
 TRACEPOINT1=kmem_cache_alloc
 TRACEPOINT2=kmem_cache_free
 
@@ -24,4 +25,17 @@ grep -q myevent1 dynamic_events
 
 echo > dynamic_events
 
+# auto naming check
+echo "t $TRACEPOINT1" >> dynamic_events
+
+test -d events/tracepoints/$TRACEPOINT1
+
+echo > dynamic_events
+
+# SUBSYSTEM is not supported
+echo "t $SUBSYSTEM/$TRACEPOINT1" >> dynamic_events && exit_fail ||:
+echo "t $SUBSYSTEM:$TRACEPOINT1" >> dynamic_events && exit_fail ||:
+echo "t:myevent3 $SUBSYSTEM/$TRACEPOINT1" >> dynamic_events && exit_fail ||:
+echo "t:myevent3 $SUBSYSTEM:$TRACEPOINT1" >> dynamic_events && exit_fail ||:
+
 clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc b/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc
new file mode 100644
index 000000000000..6b94b678741a
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc
@@ -0,0 +1,42 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Checking dynamic events limitations
+# requires: dynamic_events "imm-value":README
+
+# Max arguments limitation
+MAX_ARGS=128
+EXCEED_ARGS=$((MAX_ARGS + 1))
+
+check_max_args() { # event_header
+  TEST_STRING=$1
+  # Acceptable
+  for i in `seq 1 $MAX_ARGS`; do
+    TEST_STRING="$TEST_STRING \\$i"
+  done
+  echo "$TEST_STRING" >> dynamic_events
+  echo > dynamic_events
+  # Error
+  TEST_STRING="$TEST_STRING \\$EXCEED_ARGS"
+  ! echo "$TEST_STRING" >> dynamic_events
+  return 0
+}
+
+# Kprobe max args limitation
+if grep -q "kprobe_events" README; then
+  check_max_args "p vfs_read"
+fi
+
+# Fprobe max args limitation
+if grep -q "f[:[<group>/][<event>]] <func-name>[%return] [<args>]" README; then
+  check_max_args "f vfs_read"
+fi
+
+# Tprobe max args limitation
+if grep -q "t[:[<group>/][<event>]] <tracepoint> [<args>]" README; then
+  check_max_args "t kfree"
+fi
+
+# Uprobe max args limitation
+if grep -q "uprobe_events" README; then
+  check_max_args "p /bin/sh:10"
+fi
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
index c9425a34fae3..fee479295e2f 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
@@ -27,6 +27,7 @@ check_error 'f:^foo.1/bar vfs_read'	# BAD_GROUP_NAME
 check_error 'f:^ vfs_read'		# NO_EVENT_NAME
 check_error 'f:foo/^12345678901234567890123456789012345678901234567890123456789012345 vfs_read'	# EVENT_TOO_LONG
 check_error 'f:foo/^bar.1 vfs_read'	# BAD_EVENT_NAME
+check_error 't kmem^/kfree'       # BAD_TP_NAME
 
 check_error 'f vfs_read ^$stack10000'	# BAD_STACK_NUM