Merge tag 'trace-v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Runtime verification infrastructure

   This is the biggest change here. It introduces the runtime
   verification that is necessary for running Linux on safety critical
   systems.

   It allows for deterministic automata models to be inserted into the
   kernel that will attach to tracepoints, where the information on
   these tracepoints will move the model from state to state.

   If a state is encountered that does not belong to the model, it will
   then activate a given reactor, that could just inform the user or
   even panic the kernel (for which safety critical systems will detect
   and can recover from).

 - Two monitor models are also added: Wakeup In Preemptive (WIP - not to
   be confused with "work in progress"), and Wakeup While Not Running
   (WWNR).

 - Added __vstring() helper to the TRACE_EVENT() macro to replace
   several vsnprintf() usages that were all doing it wrong.

 - eprobes now can have their event autogenerated when the event name is
   left off.

 - The rest is various cleanups and fixes.

* tag 'trace-v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (50 commits)
  rv: Unlock on error path in rv_unregister_reactor()
  tracing: Use alignof__(struct {type b;}) instead of offsetof()
  tracing/eprobe: Show syntax error logs in error_log file
  scripts/tracing: Fix typo 'the the' in comment
  tracepoints: It is CONFIG_TRACEPOINTS not CONFIG_TRACEPOINT
  tracing: Use free_trace_buffer() in allocate_trace_buffers()
  tracing: Use a struct alignof to determine trace event field alignment
  rv/reactor: Add the panic reactor
  rv/reactor: Add the printk reactor
  rv/monitor: Add the wwnr monitor
  rv/monitor: Add the wip monitor
  rv/monitor: Add the wip monitor skeleton created by dot2k
  Documentation/rv: Add deterministic automata instrumentation documentation
  Documentation/rv: Add deterministic automata monitor synthesis documentation
  tools/rv: Add dot2k
  Documentation/rv: Add deterministic automaton documentation
  tools/rv: Add dot2c
  Documentation/rv: Add a basic documentation
  rv/include: Add instrumentation helper functions
  rv/include: Add deterministic automata monitor definition via C macros
  ...

1 files changed, 174 insertions, 0 deletions

diff --git a/tools/verification/dot2/automata.py b/tools/verification/dot2/automata.py
new file mode 100644
index 000000000000..baffeb960ff0
--- /dev/null
+++ b/tools/verification/dot2/automata.py
@@ -0,0 +1,174 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (C) 2019-2022 Red Hat, Inc. Daniel Bristot de Oliveira <bristot@kernel.org>
+#
+# Automata object: parse an automata in dot file digraph format into a python object
+#
+# For further information, see:
+#   Documentation/trace/rv/deterministic_automata.rst
+
+import ntpath
+
+class Automata:
+    """Automata class: Reads a dot file and part it as an automata.
+
+    Attributes:
+        dot_file: A dot file with an state_automaton definition.
+    """
+
+    invalid_state_str = "INVALID_STATE"
+
+    def __init__(self, file_path):
+        self.__dot_path = file_path
+        self.name = self.__get_model_name()
+        self.__dot_lines = self.__open_dot()
+        self.states, self.initial_state, self.final_states = self.__get_state_variables()
+        self.events = self.__get_event_variables()
+        self.function = self.__create_matrix()
+
+    def __get_model_name(self):
+        basename = ntpath.basename(self.__dot_path)
+        if basename.endswith(".dot") == False:
+            print("not a dot file")
+            raise Exception("not a dot file: %s" % self.__dot_path)
+
+        model_name = basename[0:-4]
+        if model_name.__len__() == 0:
+            raise Exception("not a dot file: %s" % self.__dot_path)
+
+        return model_name
+
+    def __open_dot(self):
+        cursor = 0
+        dot_lines = []
+        try:
+            dot_file = open(self.__dot_path)
+        except:
+            raise Exception("Cannot open the file: %s" % self.__dot_path)
+
+        dot_lines = dot_file.read().splitlines()
+        dot_file.close()
+
+        # checking the first line:
+        line = dot_lines[cursor].split()
+
+        if (line[0] != "digraph") and (line[1] != "state_automaton"):
+            raise Exception("Not a valid .dot format: %s" % self.__dot_path)
+        else:
+            cursor += 1
+        return dot_lines
+
+    def __get_cursor_begin_states(self):
+        cursor = 0
+        while self.__dot_lines[cursor].split()[0] != "{node":
+            cursor += 1
+        return cursor
+
+    def __get_cursor_begin_events(self):
+        cursor = 0
+        while self.__dot_lines[cursor].split()[0] != "{node":
+           cursor += 1
+        while self.__dot_lines[cursor].split()[0] == "{node":
+           cursor += 1
+        # skip initial state transition
+        cursor += 1
+        return cursor
+
+    def __get_state_variables(self):
+        # wait for node declaration
+        states = []
+        final_states = []
+
+        has_final_states = False
+        cursor = self.__get_cursor_begin_states()
+
+        # process nodes
+        while self.__dot_lines[cursor].split()[0] == "{node":
+            line = self.__dot_lines[cursor].split()
+            raw_state = line[-1]
+
+            #  "enabled_fired"}; -> enabled_fired
+            state = raw_state.replace('"', '').replace('};', '').replace(',','_')
+            if state[0:7] == "__init_":
+                initial_state = state[7:]
+            else:
+                states.append(state)
+                if self.__dot_lines[cursor].__contains__("doublecircle") == True:
+                    final_states.append(state)
+                    has_final_states = True
+
+                if self.__dot_lines[cursor].__contains__("ellipse") == True:
+                    final_states.append(state)
+                    has_final_states = True
+
+            cursor += 1
+
+        states = sorted(set(states))
+        states.remove(initial_state)
+
+        # Insert the initial state at the bein og the states
+        states.insert(0, initial_state)
+
+        if has_final_states == False:
+            final_states.append(initial_state)
+
+        return states, initial_state, final_states
+
+    def __get_event_variables(self):
+        # here we are at the begin of transitions, take a note, we will return later.
+        cursor = self.__get_cursor_begin_events()
+
+        events = []
+        while self.__dot_lines[cursor][1] == '"':
+            # transitions have the format:
+            # "all_fired" -> "both_fired" [ label = "disable_irq" ];
+            #  ------------ event is here ------------^^^^^
+            if self.__dot_lines[cursor].split()[1] == "->":
+                line = self.__dot_lines[cursor].split()
+                event = line[-2].replace('"','')
+
+                # when a transition has more than one lables, they are like this
+                # "local_irq_enable\nhw_local_irq_enable_n"
+                # so split them.
+
+                event = event.replace("\\n", " ")
+                for i in event.split():
+                    events.append(i)
+            cursor += 1
+
+        return sorted(set(events))
+
+    def __create_matrix(self):
+        # transform the array into a dictionary
+        events = self.events
+        states = self.states
+        events_dict = {}
+        states_dict = {}
+        nr_event = 0
+        for event in events:
+            events_dict[event] = nr_event
+            nr_event += 1
+
+        nr_state = 0
+        for state in states:
+            states_dict[state] = nr_state
+            nr_state += 1
+
+        # declare the matrix....
+        matrix = [[ self.invalid_state_str for x in range(nr_event)] for y in range(nr_state)]
+
+        # and we are back! Let's fill the matrix
+        cursor = self.__get_cursor_begin_events()
+
+        while self.__dot_lines[cursor][1] == '"':
+            if self.__dot_lines[cursor].split()[1] == "->":
+                line = self.__dot_lines[cursor].split()
+                origin_state = line[0].replace('"','').replace(',','_')
+                dest_state = line[2].replace('"','').replace(',','_')
+                possible_events = line[-2].replace('"','').replace("\\n", " ")
+                for event in possible_events.split():
+                    matrix[states_dict[origin_state]][events_dict[event]] = dest_state
+            cursor += 1
+
+        return matrix