Merge tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Addition of multiprobes to kprobe and uprobe events (allows for more
   than one probe attached to the same location)

 - Addition of adding immediates to probe parameters

 - Clean up of the recordmcount.c code. This brings us closer to merging
   recordmcount into objtool, and reuse code.

 - Other small clean ups

* tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
  selftests/ftrace: Update kprobe event error testcase
  tracing/probe: Reject exactly same probe event
  tracing/probe: Fix to allow user to enable events on unloaded modules
  selftests/ftrace: Select an existing function in kprobe_eventname test
  tracing/kprobe: Fix NULL pointer access in trace_porbe_unlink()
  tracing: Make sure variable reference alias has correct var_ref_idx
  tracing: Be more clever when dumping hex in __print_hex()
  ftrace: Simplify ftrace hash lookup code in clear_func_from_hash()
  tracing: Add "gfp_t" support in synthetic_events
  tracing: Rename tracing_reset() to tracing_reset_cpu()
  tracing: Document the stack trace algorithm in the comments
  tracing/arm64: Have max stack tracer handle the case of return address after data
  recordmcount: Clarify what cleanup() does
  recordmcount: Remove redundant cleanup() calls
  recordmcount: Kernel style formatting
  recordmcount: Kernel style function signature formatting
  recordmcount: Rewrite error/success handling
  selftests/ftrace: Add syntax error test for multiprobe
  selftests/ftrace: Add syntax error test for immediates
  selftests/ftrace: Add a testcase for kprobe multiprobe event
  ...

4 files changed, 67 insertions, 2 deletions

diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions
index 1d96c5f7e402..86986c4bba54 100644
--- a/tools/testing/selftests/ftrace/test.d/functions
+++ b/tools/testing/selftests/ftrace/test.d/functions
@@ -115,7 +115,7 @@ ftrace_errlog_check() { # err-prefix command-with-error-pos-by-^ command-file
     command=$(echo "$2" | tr -d ^)
     echo "Test command: $command"
     echo > error_log
-    (! echo "$command" > "$3" ) 2> /dev/null
+    (! echo "$command" >> "$3" ) 2> /dev/null
     grep "$1: error:" -A 3 error_log
     N=$(tail -n 1 error_log | wc -c)
     # "  Command: " and "^\n" => 13
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc
index 3fb70e01b1fe..3ff236719b6e 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc
@@ -24,7 +24,21 @@ test -d events/kprobes2/event2 || exit_failure
 
 :;: "Add an event on dot function without name" ;:
 
-FUNC=`grep -m 10 " [tT] .*\.isra\..*$" /proc/kallsyms | tail -n 1 | cut -f 3 -d " "`
+find_dot_func() {
+	if [ ! -f available_filter_functions ]; then
+		grep -m 10 " [tT] .*\.isra\..*$" /proc/kallsyms | tail -n 1 | cut -f 3 -d " "
+		return;
+	fi
+
+	grep " [tT] .*\.isra\..*" /proc/kallsyms | cut -f 3 -d " " | while read f; do
+		if grep -s $f available_filter_functions; then
+			echo $f
+			break
+		fi
+	done
+}
+
+FUNC=`find_dot_func | tail -n 1`
 [ "x" != "x$FUNC" ] || exit_unresolved
 echo "p $FUNC" > kprobe_events
 EVENT=`grep $FUNC kprobe_events | cut -f 1 -d " " | cut -f 2 -d:`
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_multiprobe.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_multiprobe.tc
new file mode 100644
index 000000000000..44494bac86d1
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_multiprobe.tc
@@ -0,0 +1,35 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Create/delete multiprobe on kprobe event
+
+[ -f kprobe_events ] || exit_unsupported
+
+grep -q "Create/append/" README || exit_unsupported
+
+# Choose 2 symbols for target
+SYM1=_do_fork
+SYM2=do_exit
+EVENT_NAME=kprobes/testevent
+
+DEF1="p:$EVENT_NAME $SYM1"
+DEF2="p:$EVENT_NAME $SYM2"
+
+:;: "Define an event which has 2 probes" ;:
+echo $DEF1 >> kprobe_events
+echo $DEF2 >> kprobe_events
+cat kprobe_events | grep "$DEF1"
+cat kprobe_events | grep "$DEF2"
+
+:;: "Remove the event by name (should remove both)" ;:
+echo "-:$EVENT_NAME" >> kprobe_events
+test `cat kprobe_events | wc -l` -eq 0
+
+:;: "Remove just 1 event" ;:
+echo $DEF1 >> kprobe_events
+echo $DEF2 >> kprobe_events
+echo "-:$EVENT_NAME $SYM1" >> kprobe_events
+! cat kprobe_events | grep "$DEF1"
+cat kprobe_events | grep "$DEF2"
+
+:;: "Appending different type must fail" ;:
+! echo "$DEF1 \$stack" >> kprobe_events
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
index 29faaec942c6..8a4025e912cb 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
@@ -41,6 +41,11 @@ check_error 'p vfs_read ^%none_reg'	# BAD_REG_NAME
 check_error 'p vfs_read ^@12345678abcde'	# BAD_MEM_ADDR
 check_error 'p vfs_read ^@+10'		# FILE_ON_KPROBE
 
+grep -q "imm-value" README && \
+check_error 'p vfs_read arg1=\^x'	# BAD_IMM
+grep -q "imm-string" README && \
+check_error 'p vfs_read arg1=\"abcd^'	# IMMSTR_NO_CLOSE
+
 check_error 'p vfs_read ^+0@0)'		# DEREF_NEED_BRACE
 check_error 'p vfs_read ^+0ab1(@0)'	# BAD_DEREF_OFFS
 check_error 'p vfs_read +0(+0(@0^)'	# DEREF_OPEN_BRACE
@@ -82,4 +87,15 @@ case $(uname -m) in
     ;;
 esac
 
+# multiprobe errors
+if grep -q "Create/append/" README && grep -q "imm-value" README; then
+echo 'p:kprobes/testevent _do_fork' > kprobe_events
+check_error '^r:kprobes/testevent do_exit'	# DIFF_PROBE_TYPE
+echo 'p:kprobes/testevent _do_fork abcd=\1' > kprobe_events
+check_error 'p:kprobes/testevent _do_fork ^bcd=\1'	# DIFF_ARG_TYPE
+check_error 'p:kprobes/testevent _do_fork ^abcd=\1:u8'	# DIFF_ARG_TYPE
+check_error 'p:kprobes/testevent _do_fork ^abcd=\"foo"'	# DIFF_ARG_TYPE
+check_error '^p:kprobes/testevent _do_fork'	# SAME_PROBE
+fi
+
 exit 0