selftests/ftrace: Add fprobe related testcases

Add syntax error testcase and add-remove testcase for fprobe events.
This ensures that the fprobe events can be added/removed and parser
handles syntax errors correctly.

Link: https://lore.kernel.org/all/168507470812.913472.7489900116963294042.stgit@mhiramat.roam.corp.google.com/

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

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

@@ -0,0 +1,26 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Generic dynamic event - add/remove fprobe events
+# requires: dynamic_events "f[:[<group>/][<event>]] <func-name>[%return] [<args>]": README
+
+echo 0 > events/enable
+echo > dynamic_events
+
+PLACE=$FUNCTION_FORK
+
+echo "f:myevent1 $PLACE" >> dynamic_events
+echo "f:myevent2 $PLACE%return" >> dynamic_events
+
+grep -q myevent1 dynamic_events
+grep -q myevent2 dynamic_events
+test -d events/fprobes/myevent1
+test -d events/fprobes/myevent2
+
+echo "-:myevent2" >> dynamic_events
+
+grep -q myevent1 dynamic_events
+! grep -q myevent2 dynamic_events
+
+echo > dynamic_events
+
+clear_trace

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

@@ -0,0 +1,97 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Fprobe event parser error log check
+# requires: dynamic_events "f[:[<group>/][<event>]] <func-name>[%return] [<args>]": README
+
+check_error() { # command-with-error-pos-by-^
+    ftrace_errlog_check 'trace_fprobe' "$1" 'dynamic_events'
+}
+
+case `uname -m` in
+x86_64|i[3456]86)
+  REG=%ax ;;
+aarch64)
+  REG=%x0 ;;
+*)
+  REG=%r0 ;;
+esac
+
+check_error 'f^100 vfs_read'		# MAXACT_NO_KPROBE
+check_error 'f^1a111 vfs_read'		# BAD_MAXACT
+check_error 'f^100000 vfs_read'		# MAXACT_TOO_BIG
+
+check_error 'f ^non_exist_func'		# BAD_PROBE_ADDR (enoent)
+check_error 'f ^vfs_read+10'		# BAD_PROBE_ADDR
+check_error 'f:^/bar vfs_read'		# NO_GROUP_NAME
+check_error 'f:^12345678901234567890123456789012345678901234567890123456789012345/bar vfs_read'	# GROUP_TOO_LONG
+
+check_error 'f:^foo.1/bar vfs_read'	# BAD_GROUP_NAME
+check_error 'f:^ vfs_read'		# NO_EVENT_NAME
+check_error 'f:foo/^12345678901234567890123456789012345678901234567890123456789012345 vfs_read'	# EVENT_TOO_LONG
+check_error 'f:foo/^bar.1 vfs_read'	# BAD_EVENT_NAME
+
+check_error 'f vfs_read ^$retval'	# RETVAL_ON_PROBE
+check_error 'f vfs_read ^$stack10000'	# BAD_STACK_NUM
+
+check_error 'f vfs_read ^$arg10000'	# BAD_ARG_NUM
+
+check_error 'f vfs_read ^$none_var'	# BAD_VAR
+check_error 'f vfs_read ^'$REG		# BAD_VAR
+
+check_error 'f vfs_read ^@12345678abcde'	# BAD_MEM_ADDR
+check_error 'f vfs_read ^@+10'		# FILE_ON_KPROBE
+
+grep -q "imm-value" README && \
+check_error 'f vfs_read arg1=\^x'	# BAD_IMM
+grep -q "imm-string" README && \
+check_error 'f vfs_read arg1=\"abcd^'	# IMMSTR_NO_CLOSE
+
+check_error 'f vfs_read ^+0@0)'		# DEREF_NEED_BRACE
+check_error 'f vfs_read ^+0ab1(@0)'	# BAD_DEREF_OFFS
+check_error 'f vfs_read +0(+0(@0^)'	# DEREF_OPEN_BRACE
+
+if grep -A1 "fetcharg:" README | grep -q '\$comm' ; then
+check_error 'f vfs_read +0(^$comm)'	# COMM_CANT_DEREF
+fi
+
+check_error 'f vfs_read ^&1'		# BAD_FETCH_ARG
+
+
+# We've introduced this limitation with array support
+if grep -q ' <type>\\\[<array-size>\\\]' README; then
+check_error 'f vfs_read +0(^+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(@0))))))))))))))'	# TOO_MANY_OPS?
+check_error 'f vfs_read +0(@11):u8[10^'		# ARRAY_NO_CLOSE
+check_error 'f vfs_read +0(@11):u8[10]^a'	# BAD_ARRAY_SUFFIX
+check_error 'f vfs_read +0(@11):u8[^10a]'	# BAD_ARRAY_NUM
+check_error 'f vfs_read +0(@11):u8[^256]'	# ARRAY_TOO_BIG
+fi
+
+check_error 'f vfs_read @11:^unknown_type'	# BAD_TYPE
+check_error 'f vfs_read $stack0:^string'	# BAD_STRING
+check_error 'f vfs_read @11:^b10@a/16'		# BAD_BITFIELD
+
+check_error 'f vfs_read ^arg123456789012345678901234567890=@11'	# ARG_NAME_TOO_LOG
+check_error 'f vfs_read ^=@11'			# NO_ARG_NAME
+check_error 'f vfs_read ^var.1=@11'		# BAD_ARG_NAME
+check_error 'f vfs_read var1=@11 ^var1=@12'	# USED_ARG_NAME
+check_error 'f vfs_read ^+1234567(+1234567(+1234567(+1234567(+1234567(+1234567(@1234))))))'	# ARG_TOO_LONG
+check_error 'f vfs_read arg1=^'			# NO_ARG_BODY
+
+
+# multiprobe errors
+if grep -q "Create/append/" README && grep -q "imm-value" README; then
+echo "f:fprobes/testevent $FUNCTION_FORK" > dynamic_events
+check_error '^f:fprobes/testevent do_exit%return'	# DIFF_PROBE_TYPE
+
+# Explicitly use printf "%s" to not interpret \1
+printf "%s" "f:fprobes/testevent $FUNCTION_FORK abcd=\\1" > dynamic_events
+check_error "f:fprobes/testevent $FUNCTION_FORK ^bcd=\\1"	# DIFF_ARG_TYPE
+check_error "f:fprobes/testevent $FUNCTION_FORK ^abcd=\\1:u8"	# DIFF_ARG_TYPE
+check_error "f:fprobes/testevent $FUNCTION_FORK ^abcd=\\\"foo\"" # DIFF_ARG_TYPE
+check_error "^f:fprobes/testevent $FUNCTION_FORK abcd=\\1"	# SAME_PROBE
+fi
+
+# %return suffix errors
+check_error 'f vfs_read^%hoge'		# BAD_ADDR_SUFFIX
+
+exit 0