Merge remote-tracking branch 'remotes/stefanha/tags/tracing-pull-request' into staging

Pull request

Fixes for inconsistencies in the trace event format strings, broken
trace_event_get_state() usage, and handle_qmp_command() fix.

# gpg: Signature made Tue 01 Aug 2017 14:16:05 BST
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  monitor: Reduce handle_qmp_command() tracing overhead
  trace-events: fix code style: print 0x before hex numbers
  checkpatch: check trace-events code style
  trace-events: fix code style: %# -> 0x%
  coding_style: add point about 0x in trace-events
  trace: add trace_event_get_state_backends()
  trace: add TRACE_<event>_BACKEND_DSTATE()
  trace: ensure unique function / variable names per .stp file
  trace: ensure .stp files are rebuilt if trace tool source changes

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

10 files changed, 75 insertions, 10 deletions

diff --git a/scripts/tracetool/__init__.py b/scripts/tracetool/__init__.py
index d4c204a..0670ec1 100644
--- a/scripts/tracetool/__init__.py
+++ b/scripts/tracetool/__init__.py
@@ -271,6 +271,7 @@ class Event(object):
     QEMU_TRACE_NOCHECK       = "_nocheck__" + QEMU_TRACE
     QEMU_TRACE_TCG           = QEMU_TRACE + "_tcg"
     QEMU_DSTATE              = "_TRACE_%(NAME)s_DSTATE"
+    QEMU_BACKEND_DSTATE      = "TRACE_%(NAME)s_BACKEND_DSTATE"
     QEMU_EVENT               = "_TRACE_%(NAME)s_EVENT"
 
     def api(self, fmt=None):
diff --git a/scripts/tracetool/backend/__init__.py b/scripts/tracetool/backend/__init__.py
index f735a25..259c6a6 100644
--- a/scripts/tracetool/backend/__init__.py
+++ b/scripts/tracetool/backend/__init__.py
@@ -119,5 +119,8 @@ class Wrapper:
     def generate(self, event, group):
         self._run_function("generate_%s", event, group)
 
+    def generate_backend_dstate(self, event, group):
+        self._run_function("generate_%s_backend_dstate", event, group)
+
     def generate_end(self, events, group):
         self._run_function("generate_%s_end", events, group)
diff --git a/scripts/tracetool/backend/dtrace.py b/scripts/tracetool/backend/dtrace.py
index c6812b7..c2f3a4e 100644
--- a/scripts/tracetool/backend/dtrace.py
+++ b/scripts/tracetool/backend/dtrace.py
@@ -44,8 +44,20 @@ def generate_h_begin(events, group):
     out('#include "%s"' % header,
         '')
 
+    # SystemTap defines <provider>_<name>_ENABLED() but other DTrace
+    # implementations might not.
+    for e in events:
+        out('#ifndef QEMU_%(uppername)s_ENABLED',
+            '#define QEMU_%(uppername)s_ENABLED() true',
+            '#endif',
+            uppername=e.name.upper())
 
 def generate_h(event, group):
     out('    QEMU_%(uppername)s(%(argnames)s);',
         uppername=event.name.upper(),
         argnames=", ".join(event.args.names()))
+
+
+def generate_h_backend_dstate(event, group):
+    out('    QEMU_%(uppername)s_ENABLED() || \\',
+        uppername=event.name.upper())
diff --git a/scripts/tracetool/backend/ftrace.py b/scripts/tracetool/backend/ftrace.py
index dd0eda4..92f71b2 100644
--- a/scripts/tracetool/backend/ftrace.py
+++ b/scripts/tracetool/backend/ftrace.py
@@ -45,3 +45,8 @@ def generate_h(event, group):
         event_id="TRACE_" + event.name.upper(),
         fmt=event.fmt.rstrip("\n"),
         argnames=argnames)
+
+
+def generate_h_backend_dstate(event, group):
+    out('    trace_event_get_state_dynamic_by_id(%(event_id)s) || \\',
+        event_id="TRACE_" + event.name.upper())
diff --git a/scripts/tracetool/backend/log.py b/scripts/tracetool/backend/log.py
index 54f0a69..da86f6b 100644
--- a/scripts/tracetool/backend/log.py
+++ b/scripts/tracetool/backend/log.py
@@ -48,3 +48,8 @@ def generate_h(event, group):
         name=event.name,
         fmt=event.fmt.rstrip("\n"),
         argnames=argnames)
+
+
+def generate_h_backend_dstate(event, group):
+    out('    trace_event_get_state_dynamic_by_id(%(event_id)s) || \\',
+        event_id="TRACE_" + event.name.upper())
diff --git a/scripts/tracetool/backend/simple.py b/scripts/tracetool/backend/simple.py
index f983670..c2fd1c2 100644
--- a/scripts/tracetool/backend/simple.py
+++ b/scripts/tracetool/backend/simple.py
@@ -42,6 +42,11 @@ def generate_h(event, group):
         args=", ".join(event.args.names()))
 
 
+def generate_h_backend_dstate(event, group):
+    out('    trace_event_get_state_dynamic_by_id(%(event_id)s) || \\',
+        event_id="TRACE_" + event.name.upper())
+
+
 def generate_c_begin(events, group):
     out('#include "qemu/osdep.h"',
         '#include "trace/control.h"',
diff --git a/scripts/tracetool/backend/syslog.py b/scripts/tracetool/backend/syslog.py
index 1ce627f..668fb73 100644
--- a/scripts/tracetool/backend/syslog.py
+++ b/scripts/tracetool/backend/syslog.py
@@ -42,3 +42,8 @@ def generate_h(event, group):
         name=event.name,
         fmt=event.fmt.rstrip("\n"),
         argnames=argnames)
+
+
+def generate_h_backend_dstate(event, group):
+    out('    trace_event_get_state_dynamic_by_id(%(event_id)s) || \\',
+        event_id="TRACE_" + event.name.upper())
diff --git a/scripts/tracetool/backend/ust.py b/scripts/tracetool/backend/ust.py
index 2adaf54..280cb7c 100644
--- a/scripts/tracetool/backend/ust.py
+++ b/scripts/tracetool/backend/ust.py
@@ -27,6 +27,11 @@ def generate_h_begin(events, group):
 
     out('#include <lttng/tracepoint.h>',
         '#include "%s"' % header,
+        '',
+        '/* tracepoint_enabled() was introduced in LTTng UST 2.7 */',
+        '#ifndef tracepoint_enabled',
+        '#define tracepoint_enabled(a, b) true',
+        '#endif',
         '')
 
 
@@ -38,3 +43,8 @@ def generate_h(event, group):
     out('    tracepoint(qemu, %(name)s%(tp_args)s);',
         name=event.name,
         tp_args=argnames)
+
+
+def generate_h_backend_dstate(event, group):
+    out('    tracepoint_enabled(qemu, %(name)s) || \\',
+        name=event.name)
diff --git a/scripts/tracetool/format/h.py b/scripts/tracetool/format/h.py
index aecf249..e06f0f2 100644
--- a/scripts/tracetool/format/h.py
+++ b/scripts/tracetool/format/h.py
@@ -49,6 +49,16 @@ def generate(events, backend, group):
     backend.generate_begin(events, group)
 
     for e in events:
+        # tracer-specific dstate
+        out('',
+            '#define %(api)s() ( \\',
+            api=e.api(e.QEMU_BACKEND_DSTATE))
+
+        if "disable" not in e.properties:
+            backend.generate_backend_dstate(e, group)
+
+        out('    false)')
+
         # tracer without checks
         out('',
             'static inline void %(api)s(%(args)s)',
diff --git a/scripts/tracetool/format/simpletrace_stap.py b/scripts/tracetool/format/simpletrace_stap.py
index c35e662..144b704 100644
--- a/scripts/tracetool/format/simpletrace_stap.py
+++ b/scripts/tracetool/format/simpletrace_stap.py
@@ -18,29 +18,37 @@ from tracetool.backend.dtrace import binary, probeprefix
 from tracetool.backend.simple import is_string
 from tracetool.format.stap import stap_escape
 
+def global_var_name(name):
+    return probeprefix().replace(".", "_") + "_" + name
 
 def generate(events, backend, group):
+    id_map = global_var_name("event_name_to_id_map")
+    next_id = global_var_name("event_next_id")
+    map_func = global_var_name("simple_trace_map_event")
     out('/* This file is autogenerated by tracetool, do not edit. */',
         '',
-        'global event_name_to_id_map',
-        'global event_next_id',
-        'function simple_trace_map_event(name)',
+        'global %(id_map)s',
+        'global %(next_id)s',
+        'function %(map_func)s(name)',
         '',
         '{',
-        '    if (!([name] in event_name_to_id_map)) {',
-        '        event_name_to_id_map[name] = event_next_id',
+        '    if (!([name] in %(id_map)s)) {',
+        '        %(id_map)s[name] = %(next_id)s',
         '        name_len = strlen(name)',
         '        printf("%%8b%%8b%%4b%%.*s", 0, ',
-        '               event_next_id, name_len, name_len, name)',
-        '        event_next_id = event_next_id + 1',
+        '               %(next_id)s, name_len, name_len, name)',
+        '        %(next_id)s = %(next_id)s + 1',
         '    }',
-        '    return event_name_to_id_map[name]',
+        '    return %(id_map)s[name]',
         '}',
         'probe begin',
         '{',
         '    printf("%%8b%%8b%%8b", 0xffffffffffffffff, 0xf2b177cb0aa429b4, 4)',
         '}',
-        '')
+        '',
+        id_map=id_map,
+        next_id=next_id,
+        map_func=map_func)
 
     for event_id, e in enumerate(events):
         if 'disable' in e.properties:
@@ -48,8 +56,9 @@ def generate(events, backend, group):
 
         out('probe %(probeprefix)s.simpletrace.%(name)s = %(probeprefix)s.%(name)s ?',
             '{',
-            '    id = simple_trace_map_event("%(name)s")',
+            '    id = %(map_func)s("%(name)s")',
             probeprefix=probeprefix(),
+            map_func=map_func,
             name=e.name)
 
         # Calculate record size