selftests/ftrace: Add BTF arguments test cases

Add test cases to check the BTF arguments correctly supported.

Link: https://lore.kernel.org/all/168507478292.913472.25631899274942311.stgit@mhiramat.roam.corp.google.com/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

tools/testing/selftests/ftrace/test.d/dynevent/add_remove_btfarg.tc

@@ -0,0 +1,58 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Generic dynamic event - add/remove probes with BTF arguments
+# requires: dynamic_events "<argname>":README
+
+KPROBES=
+FPROBES=
+
+if grep -qF "p[:[<group>/][<event>]] <place> [<args>]" README ; then
+  KPROBES=yes
+fi
+if grep -qF "f[:[<group>/][<event>]] <func-name>[%return] [<args>]" README ; then
+  FPROBES=yes
+fi
+
+if [ -z "$KPROBES" -a "$FPROBES" ] ; then
+  exit_unsupported
+fi
+
+echo 0 > events/enable
+echo > dynamic_events
+
+TP=kfree
+
+if [ "$FPROBES" ] ; then
+echo "f:fpevent $TP object" >> dynamic_events
+echo "t:tpevent $TP ptr" >> dynamic_events
+
+grep -q "fpevent.*object=object" dynamic_events
+grep -q "tpevent.*ptr=ptr" dynamic_events
+
+echo > dynamic_events
+
+echo "f:fpevent $TP "'$arg1' >> dynamic_events
+grep -q "fpevent.*object=object" dynamic_events
+echo > dynamic_events
+
+echo "f:fpevent $TP "'$arg*' >> dynamic_events
+echo "t:tpevent $TP "'$arg*' >> dynamic_events
+
+grep -q "fpevent.*object=object" dynamic_events
+grep -q "tpevent.*ptr=ptr" dynamic_events
+! grep -q "tpevent.*_data" dynamic_events
+fi
+
+echo > dynamic_events
+
+if [ "$KPROBES" ] ; then
+echo "p:kpevent $TP object" >> dynamic_events
+grep -q "kpevent.*object=object" dynamic_events
+
+echo > dynamic_events
+
+echo "p:kpevent $TP "'$arg*' >> dynamic_events
+grep -q "kpevent.*object=object" dynamic_events
+fi
+
+clear_trace

tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc

@@ -94,4 +94,18 @@ fi
 # %return suffix errors
 check_error 'f vfs_read^%hoge'		# BAD_ADDR_SUFFIX
 
+# BTF arguments errors
+if grep -q "<argname>" README; then
+check_error 'f vfs_read args=^$arg*'		# BAD_VAR_ARGS
+check_error 'f vfs_read +0(^$arg*)'		# BAD_VAR_ARGS
+check_error 'f vfs_read $arg* ^$arg*'		# DOUBLE_ARGS
+check_error 'f vfs_read%return ^$arg*'		# NOFENTRY_ARGS
+check_error 'f vfs_read ^hoge'			# NO_BTFARG
+check_error 'f kfree ^$arg10'			# NO_BTFARG (exceed the number of parameters)
+check_error 'f kfree%return ^$retval'		# NO_RETVAL
+else
+check_error 'f vfs_read ^$arg*'			# NOSUP_BTFARG
+check_error 't kfree ^$arg*'			# NOSUP_BTFARG
+fi
+
 exit 0

tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc

@@ -103,4 +103,18 @@ check_error 'p vfs_read^%hoge'		# BAD_ADDR_SUFFIX
 check_error 'p ^vfs_read+10%return'	# BAD_RETPROBE
 fi
 
+# BTF arguments errors
+if grep -q "<argname>" README; then
+check_error 'p vfs_read args=^$arg*'		# BAD_VAR_ARGS
+check_error 'p vfs_read +0(^$arg*)'		# BAD_VAR_ARGS
+check_error 'p vfs_read $arg* ^$arg*'		# DOUBLE_ARGS
+check_error 'r vfs_read ^$arg*'			# NOFENTRY_ARGS
+check_error 'p vfs_read+8 ^$arg*'		# NOFENTRY_ARGS
+check_error 'p vfs_read ^hoge'			# NO_BTFARG
+check_error 'p kfree ^$arg10'			# NO_BTFARG (exceed the number of parameters)
+check_error 'r kfree ^$retval'			# NO_RETVAL
+else
+check_error 'p vfs_read ^$arg*'			# NOSUP_BTFARG
+fi
+
 exit 0