[PULL v2 08/25] trace: drop 'id' from TraceEvent struct when not required

[Stefan Hajnoczi <stefanha@redhat.com>]

From: Daniel P. Berrangé <berrange@redhat.com>

Only "simpletrace" uses the "id" field from the TraceEvent struct.
Omit it when this backend is not enabled to save memory.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20261102142844.3464712-9-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 trace/control-internal.h      | 2 ++
 trace/control.h               | 3 ++-
 trace/event-internal.h        | 2 ++
 tests/tracetool/dtrace.c      | 4 ++++
 tests/tracetool/ftrace.c      | 4 ++++
 tests/tracetool/log.c         | 4 ++++
 tests/tracetool/simple.c      | 4 ++++
 tests/tracetool/syslog.c      | 4 ++++
 tests/tracetool/ust.c         | 4 ++++
 trace/control.c               | 4 +++-
 scripts/tracetool/format/c.py | 2 ++
 11 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/trace/control-internal.h b/trace/control-internal.h
index 8d818d359be..f626b047264 100644
--- a/trace/control-internal.h
+++ b/trace/control-internal.h
@@ -19,11 +19,13 @@ static inline bool trace_event_is_pattern(const char *str)
     return strchr(str, '*') != NULL;
 }
 
+#ifdef CONFIG_TRACE_SIMPLE
 static inline uint32_t trace_event_get_id(TraceEvent *ev)
 {
     assert(ev != NULL);
     return ev->id;
 }
+#endif
 
 static inline const char * trace_event_get_name(TraceEvent *ev)
 {
diff --git a/trace/control.h b/trace/control.h
index 20033fb6669..e77c07a8e68 100644
--- a/trace/control.h
+++ b/trace/control.h
@@ -81,13 +81,14 @@ TraceEvent *trace_event_name(const char *name);
  */
 static bool trace_event_is_pattern(const char *str);
 
-
+#ifdef CONFIG_TRACE_SIMPLE
 /**
  * trace_event_get_id:
  *
  * Get the identifier of an event.
  */
 static uint32_t trace_event_get_id(TraceEvent *ev);
+#endif
 
 /**
  * trace_event_get_name:
diff --git a/trace/event-internal.h b/trace/event-internal.h
index cc095a6ad54..ecf2caabd03 100644
--- a/trace/event-internal.h
+++ b/trace/event-internal.h
@@ -20,7 +20,9 @@
  * Opaque generic description of a tracing event.
  */
 typedef struct TraceEvent {
+#ifdef CONFIG_TRACE_SIMPLE
     uint32_t id;
+#endif
     const char * name;
     const bool sstate;
     uint16_t *dstate;
diff --git a/tests/tracetool/dtrace.c b/tests/tracetool/dtrace.c
index 9f862fa14d2..05a93918240 100644
--- a/tests/tracetool/dtrace.c
+++ b/tests/tracetool/dtrace.c
@@ -8,13 +8,17 @@
 uint16_t _TRACE_TEST_BLAH_DSTATE;
 uint16_t _TRACE_TEST_WIBBLE_DSTATE;
 TraceEvent _TRACE_TEST_BLAH_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_blah",
     .sstate = TRACE_TEST_BLAH_ENABLED,
     .dstate = &_TRACE_TEST_BLAH_DSTATE
 };
 TraceEvent _TRACE_TEST_WIBBLE_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_wibble",
     .sstate = TRACE_TEST_WIBBLE_ENABLED,
     .dstate = &_TRACE_TEST_WIBBLE_DSTATE
diff --git a/tests/tracetool/ftrace.c b/tests/tracetool/ftrace.c
index 9f862fa14d2..05a93918240 100644
--- a/tests/tracetool/ftrace.c
+++ b/tests/tracetool/ftrace.c
@@ -8,13 +8,17 @@
 uint16_t _TRACE_TEST_BLAH_DSTATE;
 uint16_t _TRACE_TEST_WIBBLE_DSTATE;
 TraceEvent _TRACE_TEST_BLAH_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_blah",
     .sstate = TRACE_TEST_BLAH_ENABLED,
     .dstate = &_TRACE_TEST_BLAH_DSTATE
 };
 TraceEvent _TRACE_TEST_WIBBLE_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_wibble",
     .sstate = TRACE_TEST_WIBBLE_ENABLED,
     .dstate = &_TRACE_TEST_WIBBLE_DSTATE
diff --git a/tests/tracetool/log.c b/tests/tracetool/log.c
index 9f862fa14d2..05a93918240 100644
--- a/tests/tracetool/log.c
+++ b/tests/tracetool/log.c
@@ -8,13 +8,17 @@
 uint16_t _TRACE_TEST_BLAH_DSTATE;
 uint16_t _TRACE_TEST_WIBBLE_DSTATE;
 TraceEvent _TRACE_TEST_BLAH_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_blah",
     .sstate = TRACE_TEST_BLAH_ENABLED,
     .dstate = &_TRACE_TEST_BLAH_DSTATE
 };
 TraceEvent _TRACE_TEST_WIBBLE_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_wibble",
     .sstate = TRACE_TEST_WIBBLE_ENABLED,
     .dstate = &_TRACE_TEST_WIBBLE_DSTATE
diff --git a/tests/tracetool/simple.c b/tests/tracetool/simple.c
index 0484177481c..490d6f379a5 100644
--- a/tests/tracetool/simple.c
+++ b/tests/tracetool/simple.c
@@ -8,13 +8,17 @@
 uint16_t _TRACE_TEST_BLAH_DSTATE;
 uint16_t _TRACE_TEST_WIBBLE_DSTATE;
 TraceEvent _TRACE_TEST_BLAH_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_blah",
     .sstate = TRACE_TEST_BLAH_ENABLED,
     .dstate = &_TRACE_TEST_BLAH_DSTATE
 };
 TraceEvent _TRACE_TEST_WIBBLE_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_wibble",
     .sstate = TRACE_TEST_WIBBLE_ENABLED,
     .dstate = &_TRACE_TEST_WIBBLE_DSTATE
diff --git a/tests/tracetool/syslog.c b/tests/tracetool/syslog.c
index 9f862fa14d2..05a93918240 100644
--- a/tests/tracetool/syslog.c
+++ b/tests/tracetool/syslog.c
@@ -8,13 +8,17 @@
 uint16_t _TRACE_TEST_BLAH_DSTATE;
 uint16_t _TRACE_TEST_WIBBLE_DSTATE;
 TraceEvent _TRACE_TEST_BLAH_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_blah",
     .sstate = TRACE_TEST_BLAH_ENABLED,
     .dstate = &_TRACE_TEST_BLAH_DSTATE
 };
 TraceEvent _TRACE_TEST_WIBBLE_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_wibble",
     .sstate = TRACE_TEST_WIBBLE_ENABLED,
     .dstate = &_TRACE_TEST_WIBBLE_DSTATE
diff --git a/tests/tracetool/ust.c b/tests/tracetool/ust.c
index 9f862fa14d2..05a93918240 100644
--- a/tests/tracetool/ust.c
+++ b/tests/tracetool/ust.c
@@ -8,13 +8,17 @@
 uint16_t _TRACE_TEST_BLAH_DSTATE;
 uint16_t _TRACE_TEST_WIBBLE_DSTATE;
 TraceEvent _TRACE_TEST_BLAH_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_blah",
     .sstate = TRACE_TEST_BLAH_ENABLED,
     .dstate = &_TRACE_TEST_BLAH_DSTATE
 };
 TraceEvent _TRACE_TEST_WIBBLE_EVENT = {
+#ifdef CONFIG_TRACE_SIMPLE
     .id = 0,
+#endif
     .name = "test_wibble",
     .sstate = TRACE_TEST_WIBBLE_ENABLED,
     .dstate = &_TRACE_TEST_WIBBLE_DSTATE
diff --git a/trace/control.c b/trace/control.c
index 6971157cbe7..947b220056a 100644
--- a/trace/control.c
+++ b/trace/control.c
@@ -36,8 +36,8 @@ typedef struct TraceEventGroup {
 
 static TraceEventGroup *event_groups;
 static size_t nevent_groups;
-static uint32_t next_id;
 #ifdef CONFIG_TRACE_SIMPLE
+static uint32_t next_id;
 static bool init_trace_on_startup;
 #endif
 static char *trace_opts_file;
@@ -65,10 +65,12 @@ QemuOptsList qemu_trace_opts = {
 
 void trace_event_register_group(TraceEvent **events)
 {
+#ifdef CONFIG_TRACE_SIMPLE
     size_t i;
     for (i = 0; events[i] != NULL; i++) {
         events[i]->id = next_id++;
     }
+#endif
     event_groups = g_renew(TraceEventGroup, event_groups, nevent_groups + 1);
     event_groups[nevent_groups].events = events;
     nevent_groups++;
diff --git a/scripts/tracetool/format/c.py b/scripts/tracetool/format/c.py
index 50e03313cbf..abe738ac423 100644
--- a/scripts/tracetool/format/c.py
+++ b/scripts/tracetool/format/c.py
@@ -34,7 +34,9 @@ def generate(events, backend, group):
 
     for e in events:
         out('TraceEvent %(event)s = {',
+            '#ifdef CONFIG_TRACE_SIMPLE',
             '    .id = 0,',
+            '#endif',
             '    .name = \"%(name)s\",',
             '    .sstate = %(sstate)s,',
             '    .dstate = &%(dstate)s',
-- 
2.56.0