Merge branch 'sysprof' into 'master'

Add initial sysprof support

See merge request !1551

docs/reference/glib/meson.build

@@ -22,6 +22,7 @@ if get_option('gtk_doc')
     'gprintfint.h',
     'gmirroringtable.h',
     'gscripttable.h',
+    'gtrace-private.h',
     'glib-mirroring-tab',
     'gnulib',
     'pcre',

gio/gasyncinitable.c

@@ -87,6 +87,7 @@
  *   GTask *task;
  *
  *   task = g_task_new (initable, cancellable, callback, user_data);
+ *   g_task_set_name (task, G_STRFUNC);
  *
  *   switch (self->priv->state)
  *     {

gio/gdbusinterfaceskeleton.c

@@ -632,6 +632,7 @@ g_dbus_interface_method_dispatch_helper (GDBusInterfaceSkeleton       *interface
 
       task = g_task_new (interface, NULL, NULL, NULL);
       g_task_set_source_tag (task, g_dbus_interface_method_dispatch_helper);
+      g_task_set_name (task, "[gio] D-Bus interface method dispatch");
       g_task_set_task_data (task, data, (GDestroyNotify) dispatch_data_unref);
       g_task_run_in_thread (task, dispatch_in_thread_func);
       g_object_unref (task);

gio/gdbusprivate.c

@@ -183,6 +183,7 @@ _g_socket_read_with_control_messages (GSocket                 *socket,
 
   task = g_task_new (socket, cancellable, callback, user_data);
   g_task_set_source_tag (task, _g_socket_read_with_control_messages);
+  g_task_set_name (task, "[gio] D-Bus read");
   g_task_set_task_data (task, data, (GDestroyNotify) read_with_control_data_free);
 
   if (g_socket_condition_check (socket, G_IO_IN))
@@ -1123,6 +1124,7 @@ write_message_async (GDBusWorker         *worker,
 {
   data->task = g_task_new (NULL, NULL, callback, user_data);
   g_task_set_source_tag (data->task, write_message_async);
+  g_task_set_name (data->task, "[gio] D-Bus write message");
   data->total_written = 0;
   write_message_continue_writing (data);
 }

gio/gdbusproxy.c

@@ -1631,6 +1631,7 @@ async_initable_init_second_async (GAsyncInitable      *initable,
 
   task = g_task_new (proxy, cancellable, callback, user_data);
   g_task_set_source_tag (task, async_initable_init_second_async);
+  g_task_set_name (task, "[gio] D-Bus proxy init");
   g_task_set_priority (task, io_priority);
 
   /* Check name ownership asynchronously - possibly also start the service */
@@ -1802,6 +1803,7 @@ async_initable_init_async (GAsyncInitable      *initable,
 
   task = g_task_new (proxy, cancellable, callback, user_data);
   g_task_set_source_tag (task, async_initable_init_async);
+  g_task_set_name (task, "[gio] D-Bus proxy init");
   g_task_set_priority (task, io_priority);
 
   if (proxy->priv->bus_type != G_BUS_TYPE_NONE)
@@ -2649,6 +2651,7 @@ g_dbus_proxy_call_internal (GDBusProxy          *proxy,
       my_callback = (GAsyncReadyCallback) reply_cb;
       task = g_task_new (proxy, cancellable, callback, user_data);
       g_task_set_source_tag (task, g_dbus_proxy_call_internal);
+      g_task_set_name (task, "[gio] D-Bus proxy call");
     }
   else
     {

gio/gresolver.c

@@ -576,6 +576,7 @@ lookup_by_name_async_real (GResolver                *resolver,
 
       task = g_task_new (resolver, cancellable, callback, user_data);
       g_task_set_source_tag (task, lookup_by_name_async_real);
+      g_task_set_name (task, "[gio] resolver lookup");
       if (addrs)
         g_task_return_pointer (task, addrs, (GDestroyNotify) g_resolver_free_addresses);
       else
@@ -595,6 +596,7 @@ lookup_by_name_async_real (GResolver                *resolver,
                            _("Invalid hostname"));
       task = g_task_new (resolver, cancellable, callback, user_data);
       g_task_set_source_tag (task, lookup_by_name_async_real);
+      g_task_set_name (task, "[gio] resolver lookup");
       g_task_return_error (task, error);
       g_object_unref (task);
       return;
@@ -613,6 +615,7 @@ lookup_by_name_async_real (GResolver                *resolver,
                        _("%s not implemented"), "lookup_by_name_with_flags_async");
           task = g_task_new (resolver, cancellable, callback, user_data);
           g_task_set_source_tag (task, lookup_by_name_async_real);
+          g_task_set_name (task, "[gio] resolver lookup");
           g_task_return_error (task, error);
           g_object_unref (task);
         }

gio/gtask.c

@@ -759,6 +759,7 @@ g_task_report_error (gpointer             source_object,
 
   task = g_task_new (source_object, NULL, callback, callback_data);
   g_task_set_source_tag (task, source_tag);
+  g_task_set_name (task, G_STRFUNC);
   g_task_return_error (task, error);
   g_object_unref (task);
 }
@@ -982,8 +983,8 @@ g_task_set_return_on_cancel (GTask    *task,
  * Since: 2.36
  */
 void
-g_task_set_source_tag (GTask    *task,
-                       gpointer  source_tag)
+(g_task_set_source_tag) (GTask    *task,
+                         gpointer  source_tag)
 {
   g_return_if_fail (G_IS_TASK (task));
 
@@ -1241,6 +1242,7 @@ g_task_return (GTask           *task,
                GTaskReturnType  type)
 {
   GSource *source;
+  gchar *source_name = NULL;
 
   if (type != G_TASK_RETURN_FROM_THREAD)
     task->ever_returned = TRUE;
@@ -1289,7 +1291,10 @@ g_task_return (GTask           *task,
 
   /* Otherwise, complete in the next iteration */
   source = g_idle_source_new ();
-  g_source_set_name (source, "[gio] complete_in_idle_cb");
+  source_name = g_strdup_printf ("[gio] %s complete_in_idle_cb",
+                                 (task->name != NULL) ? task->name : "(unnamed)");
+  g_source_set_name (source, source_name);
+  g_free (source_name);
   g_task_attach_source (task, source, complete_in_idle_cb);
   g_source_unref (source);
 }

gio/gtask.h

@@ -78,6 +78,14 @@ GLIB_AVAILABLE_IN_2_60
 void          g_task_set_name              (GTask               *task,
                                             const gchar         *name);
 
+/* Macro wrapper to set the task name when setting the source tag. */
+#define g_task_set_source_tag(task, tag) G_STMT_START { \
+  GTask *_task = (task); \
+  (g_task_set_source_tag) (_task, tag); \
+  if (g_task_get_name (_task) == NULL) \
+    g_task_set_name (_task, G_STRINGIFY (tag)); \
+} G_STMT_END
+
 GLIB_AVAILABLE_IN_2_36
 gpointer      g_task_get_source_object     (GTask               *task);
 GLIB_AVAILABLE_IN_2_36

gio/gthreadedresolver.c

@@ -187,6 +187,7 @@ lookup_by_name (GResolver     *resolver,
   data = lookup_data_new (hostname, AF_UNSPEC);
   task = g_task_new (resolver, cancellable, NULL, NULL);
   g_task_set_source_tag (task, lookup_by_name);
+  g_task_set_name (task, "[gio] resolver lookup");
   g_task_set_task_data (task, data, (GDestroyNotify)lookup_data_free);
   g_task_set_return_on_cancel (task, TRUE);
   g_task_run_in_thread_sync (task, do_lookup_by_name);
@@ -228,6 +229,7 @@ lookup_by_name_with_flags (GResolver                 *resolver,
   data = lookup_data_new (hostname, AF_UNSPEC);
   task = g_task_new (resolver, cancellable, NULL, NULL);
   g_task_set_source_tag (task, lookup_by_name_with_flags);
+  g_task_set_name (task, "[gio] resolver lookup");
   g_task_set_task_data (task, data, (GDestroyNotify)lookup_data_free);
   g_task_set_return_on_cancel (task, TRUE);
   g_task_run_in_thread_sync (task, do_lookup_by_name);
@@ -251,6 +253,7 @@ lookup_by_name_with_flags_async (GResolver                *resolver,
   data = lookup_data_new (hostname, flags_to_family (flags));
   task = g_task_new (resolver, cancellable, callback, user_data);
   g_task_set_source_tag (task, lookup_by_name_with_flags_async);
+  g_task_set_name (task, "[gio] resolver lookup");
   g_task_set_task_data (task, data, (GDestroyNotify)lookup_data_free);
   g_task_set_return_on_cancel (task, TRUE);
   g_task_run_in_thread (task, do_lookup_by_name);
@@ -350,6 +353,7 @@ lookup_by_address (GResolver        *resolver,
 
   task = g_task_new (resolver, cancellable, NULL, NULL);
   g_task_set_source_tag (task, lookup_by_address);
+  g_task_set_name (task, "[gio] resolver lookup");
   g_task_set_task_data (task, g_object_ref (address), g_object_unref);
   g_task_set_return_on_cancel (task, TRUE);
   g_task_run_in_thread_sync (task, do_lookup_by_address);
@@ -370,6 +374,7 @@ lookup_by_address_async (GResolver           *resolver,
 
   task = g_task_new (resolver, cancellable, callback, user_data);
   g_task_set_source_tag (task, lookup_by_address_async);
+  g_task_set_name (task, "[gio] resolver lookup");
   g_task_set_task_data (task, g_object_ref (address), g_object_unref);
   g_task_set_return_on_cancel (task, TRUE);
   g_task_run_in_thread (task, do_lookup_by_address);
@@ -1040,6 +1045,7 @@ lookup_records (GResolver              *resolver,
 
   task = g_task_new (resolver, cancellable, NULL, NULL);
   g_task_set_source_tag (task, lookup_records);
+  g_task_set_name (task, "[gio] resolver lookup records");
 
   lrd = g_slice_new (LookupRecordsData);
   lrd->rrname = g_strdup (rrname);
@@ -1067,6 +1073,7 @@ lookup_records_async (GResolver           *resolver,
 
   task = g_task_new (resolver, cancellable, callback, user_data);
   g_task_set_source_tag (task, lookup_records_async);
+  g_task_set_name (task, "[gio] resolver lookup records");
 
   lrd = g_slice_new (LookupRecordsData);
   lrd->rrname = g_strdup (rrname);

gio/gtlsdatabase.c

@@ -186,6 +186,7 @@ g_tls_database_real_verify_chain_async (GTlsDatabase           *self,
 
   task = g_task_new (self, cancellable, callback, user_data);
   g_task_set_source_tag (task, g_tls_database_real_verify_chain_async);
+  g_task_set_name (task, "[gio] verify TLS chain");
   g_task_set_task_data (task, args, async_verify_chain_free);
   g_task_run_in_thread (task, async_verify_chain_thread);
   g_object_unref (task);
@@ -264,6 +265,7 @@ g_tls_database_real_lookup_certificate_for_handle_async (GTlsDatabase
   task = g_task_new (self, cancellable, callback, user_data);
   g_task_set_source_tag (task,
                          g_tls_database_real_lookup_certificate_for_handle_async);
+  g_task_set_name (task, "[gio] lookup TLS certificate");
   g_task_set_task_data (task, args, async_lookup_certificate_for_handle_free);
   g_task_run_in_thread (task, async_lookup_certificate_for_handle_thread);
   g_object_unref (task);
@@ -338,6 +340,7 @@ g_tls_database_real_lookup_certificate_issuer_async (GTlsDatabase           *sel
   task = g_task_new (self, cancellable, callback, user_data);
   g_task_set_source_tag (task,
                          g_tls_database_real_lookup_certificate_issuer_async);
+  g_task_set_name (task, "[gio] lookup certificate issuer");
   g_task_set_task_data (task, args, async_lookup_certificate_issuer_free);
   g_task_run_in_thread (task, async_lookup_certificate_issuer_thread);
   g_object_unref (task);
@@ -419,6 +422,7 @@ g_tls_database_real_lookup_certificates_issued_by_async (GTlsDatabase
   task = g_task_new (self, cancellable, callback, user_data);
   g_task_set_source_tag (task,
                          g_tls_database_real_lookup_certificates_issued_by_async);
+  g_task_set_name (task, "[gio] lookup certificates issued by");
   g_task_set_task_data (task, args, async_lookup_certificates_issued_by_free);
   g_task_run_in_thread (task, async_lookup_certificates_issued_by_thread);
   g_object_unref (task);

gio/gunixmount.c

@@ -302,7 +302,8 @@ eject_unmount_do (GMount              *mount,
                   GCancellable        *cancellable,
                   GAsyncReadyCallback  callback,
                   gpointer             user_data,
-                  char               **argv)
+                  char               **argv,
+                  const gchar         *task_name)
 {
   GUnixMount *unix_mount = G_UNIX_MOUNT (mount);
   GTask *task;
@@ -310,6 +311,7 @@ eject_unmount_do (GMount              *mount,
 
   task = g_task_new (mount, cancellable, callback, user_data);
   g_task_set_source_tag (task, eject_unmount_do);
+  g_task_set_name (task, task_name);
   g_task_set_task_data (task, g_strdupv (argv), (GDestroyNotify) g_strfreev);
 
   if (unix_mount->volume_monitor != NULL)
@@ -337,7 +339,7 @@ g_unix_mount_unmount (GMount             *mount,
   else
     argv[1] = unix_mount->device_path;
 
-  eject_unmount_do (mount, cancellable, callback, user_data, argv);
+  eject_unmount_do (mount, cancellable, callback, user_data, argv, "[gio] unmount mount");
 }
 
 static gboolean
@@ -363,7 +365,7 @@ g_unix_mount_eject (GMount             *mount,
   else
     argv[1] = unix_mount->device_path;
 
-  eject_unmount_do (mount, cancellable, callback, user_data, argv);
+  eject_unmount_do (mount, cancellable, callback, user_data, argv, "[gio] eject mount");
 }
 
 static gboolean

gio/gunixvolume.c

@@ -305,7 +305,8 @@ eject_mount_do (GVolume              *volume,
                 GCancellable         *cancellable,
                 GAsyncReadyCallback   callback,
                 gpointer              user_data,
-                const gchar * const  *argv)
+                const gchar * const  *argv,
+                const gchar          *task_name)
 {
   GSubprocess *subprocess;
   GError *error = NULL;
@@ -313,6 +314,7 @@ eject_mount_do (GVolume              *volume,
 
   task = g_task_new (volume, cancellable, callback, user_data);
   g_task_set_source_tag (task, eject_mount_do);
+  g_task_set_name (task, task_name);
 
   if (g_task_return_error_if_cancelled (task))
     {
@@ -344,7 +346,7 @@ g_unix_volume_mount (GVolume            *volume,
   else
     argv[1] = unix_volume->device_path;
 
-  eject_mount_do (volume, cancellable, callback, user_data, argv);
+  eject_mount_do (volume, cancellable, callback, user_data, argv, "[gio] mount volume");
 }
 
 static gboolean
@@ -369,7 +371,7 @@ g_unix_volume_eject (GVolume             *volume,
 
   argv[1] = unix_volume->device_path;
 
-  eject_mount_do (volume, cancellable, callback, user_data, argv);
+  eject_mount_do (volume, cancellable, callback, user_data, argv, "[gio] eject volume");
 }
 
 static gboolean

glib/gmain.c

@@ -88,6 +88,7 @@
 #include "gstrfuncs.h"
 #include "gtestutils.h"
 #include "gthreadprivate.h"
+#include "gtrace-private.h"
 
 #ifdef G_OS_WIN32
 #include "gwin32.h"
@@ -1248,6 +1249,12 @@ g_source_attach_unlocked (GSource      *source,
   if (do_wakeup && context->owner && context->owner != G_THREAD_SELF)
     g_wakeup_signal (context->wakeup);
 
+  g_trace_mark (G_TRACE_CURRENT_TIME, 0,
+                "GLib", "g_source_attach",
+                "%s to context %p",
+                (g_source_get_name (source) != NULL) ? g_source_get_name (source) : "(unnamed)",
+                context);
+
   return source->source_id;
 }
 
@@ -3291,6 +3298,7 @@ g_main_dispatch (GMainContext *context)
 				GSourceFunc,
 				gpointer);
           GSource *prev_source;
+          gint64 begin_time_nsec G_GNUC_UNUSED;
 
 	  dispatch = source->source_funcs->dispatch;
 	  cb_funcs = source->callback_funcs;
@@ -3317,12 +3325,20 @@ g_main_dispatch (GMainContext *context)
           current->source = source;
           current->depth++;
 
+          begin_time_nsec = G_TRACE_CURRENT_TIME;
+
           TRACE (GLIB_MAIN_BEFORE_DISPATCH (g_source_get_name (source), source,
                                             dispatch, callback, user_data));
           need_destroy = !(* dispatch) (source, callback, user_data);
           TRACE (GLIB_MAIN_AFTER_DISPATCH (g_source_get_name (source), source,
                                            dispatch, need_destroy));
 
+          g_trace_mark (begin_time_nsec, G_TRACE_CURRENT_TIME - begin_time_nsec,
+                        "GLib", "GSource.dispatch",
+                        "%s ⇒ %s",
+                        (g_source_get_name (source) != NULL) ? g_source_get_name (source) : "(unnamed)",
+                        need_destroy ? "destroy" : "keep");
+
           current->source = prev_source;
           current->depth--;
 
@@ -3626,12 +3642,22 @@ g_main_context_prepare (GMainContext *context,
 
           if (prepare)
             {
+              gint64 begin_time_nsec G_GNUC_UNUSED;
+
               context->in_check_or_prepare++;
               UNLOCK_CONTEXT (context);
 
+              begin_time_nsec = G_TRACE_CURRENT_TIME;
+
               result = (* prepare) (source, &source_timeout);
               TRACE (GLIB_MAIN_AFTER_PREPARE (source, prepare, source_timeout));
 
+              g_trace_mark (begin_time_nsec, G_TRACE_CURRENT_TIME - begin_time_nsec,
+                            "GLib", "GSource.prepare",
+                            "%s ⇒ %s",
+                            (g_source_get_name (source) != NULL) ? g_source_get_name (source) : "(unnamed)",
+                            result ? "ready" : "unready");
+
               LOCK_CONTEXT (context);
               context->in_check_or_prepare--;
             }
@@ -3886,14 +3912,24 @@ g_main_context_check (GMainContext *context,
 
           if (check)
             {
+              gint64 begin_time_nsec G_GNUC_UNUSED;
+
               /* If the check function is set, call it. */
               context->in_check_or_prepare++;
               UNLOCK_CONTEXT (context);
 
+              begin_time_nsec = G_TRACE_CURRENT_TIME;
+
               result = (* check) (source);
 
               TRACE (GLIB_MAIN_AFTER_CHECK (source, check, result));
 
+              g_trace_mark (begin_time_nsec, G_TRACE_CURRENT_TIME - begin_time_nsec,
+                            "GLib", "GSource.check",
+                            "%s ⇒ %s",
+                            (g_source_get_name (source) != NULL) ? g_source_get_name (source) : "(unnamed)",
+                            result ? "dispatch" : "ignore");
+
               LOCK_CONTEXT (context);
               context->in_check_or_prepare--;
             }
@@ -4004,9 +4040,12 @@ g_main_context_iterate (GMainContext *context,
   gboolean some_ready;
   gint nfds, allocated_nfds;
   GPollFD *fds = NULL;
+  gint64 begin_time_nsec G_GNUC_UNUSED;
 
   UNLOCK_CONTEXT (context);
 
+  begin_time_nsec = G_TRACE_CURRENT_TIME;
+
   if (!g_main_context_acquire (context))
     {
       gboolean got_ownership;
@@ -4061,6 +4100,10 @@ g_main_context_iterate (GMainContext *context,
   
   g_main_context_release (context);
 
+  g_trace_mark (begin_time_nsec, G_TRACE_CURRENT_TIME - begin_time_nsec,
+                "GLib", "g_main_context_iterate",
+                "Context %p, %s ⇒ %s", context, block ? "blocking" : "non-blocking", some_ready ? "dispatched" : "nothing");
+
   LOCK_CONTEXT (context);
 
   return some_ready;

glib/gspawn.c

@@ -54,6 +54,7 @@
 #include "gspawn.h"
 #include "gspawn-private.h"
 #include "gthread.h"
+#include "gtrace-private.h"
 #include "glib/gstdio.h"
 
 #include "genviron.h"
@@ -1760,7 +1761,10 @@ fork_exec_with_fds (gboolean              intermediate_child,
   if (!intermediate_child && working_directory == NULL && !close_descriptors &&
       !search_path_from_envp && child_setup == NULL)
     {
-      g_debug ("Launching with posix_spawn");
+      g_trace_mark (G_TRACE_CURRENT_TIME, 0,
+                    "GLib", "posix_spawn",
+                    "%s", argv[0]);
+
       status = do_posix_spawn (argv,
                                envp,
                                search_path,
@@ -1796,12 +1800,14 @@ fork_exec_with_fds (gboolean              intermediate_child,
     }
   else
     {
-      g_debug ("posix_spawn avoided %s%s%s%s%s",
-               !intermediate_child ? "" : "(automatic reaping requested) ",
-               working_directory == NULL ? "" : "(workdir specified) ",
-               !close_descriptors ? "" : "(fd close requested) ",
-               !search_path_from_envp ? "" : "(using envp for search path) ",
-               child_setup == NULL ? "" : "(child_setup specified) ");
+      g_trace_mark (G_TRACE_CURRENT_TIME, 0,
+                    "GLib", "fork",
+                    "posix_spawn avoided %s%s%s%s%s",
+                    !intermediate_child ? "" : "(automatic reaping requested) ",
+                    working_directory == NULL ? "" : "(workdir specified) ",
+                    !close_descriptors ? "" : "(fd close requested) ",
+                    !search_path_from_envp ? "" : "(using envp for search path) ",
+                    child_setup == NULL ? "" : "(child_setup specified) ");
     }
 #endif /* POSIX_SPAWN_AVAILABLE */
 

glib/gtrace-private.h

+/*
+ * Copyright © 2020 Endless Mobile, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Philip Withnall <withnall@endlessm.com>
+ */
+
+#pragma once
+
+#ifdef HAVE_SYSPROF
+#include <sysprof-capture.h>
+#endif
+
+#include "gmem.h"
+#include "gmacros.h"
+
+G_BEGIN_DECLS
+
+/*
+ * G_TRACE_CURRENT_TIME:
+ *
+ * Get the current time, in nanoseconds since the tracing epoch. This (and only
+ * this) is suitable for passing to tracing functions like g_trace_mark(). It is
+ * not suitable for other timekeeping.
+ *
+ * The tracing epoch is implementation defined, but is guaranteed to be
+ * unchanged within the lifetime of each thread. It is not comparable across
+ * threads or process instances.
+ *
+ * If tracing support is disabled, this evaluates to `0`.
+ *
+ * Since: 2.66
+ */
+#ifdef HAVE_SYSPROF
+#define G_TRACE_CURRENT_TIME SYSPROF_CAPTURE_CURRENT_TIME
+#else
+#define G_TRACE_CURRENT_TIME 0
+#endif
+
+void (g_trace_mark) (gint64       begin_time_nsec,
+                     gint64       duration_nsec,
+                     const gchar *group,
+                     const gchar *name,
+                     const gchar *message_format,
+                     ...);
+
+#ifndef HAVE_SYSPROF
+/* Optimise the whole call out */
+#if defined(G_HAVE_ISO_VARARGS)
+#define g_trace_mark(b, d, g, n, m, ...)
+#elif defined(G_HAVE_GNUC_VARARGS)
+#define g_trace_mark(b, d, g, n, m...)
+#else
+/* no varargs macro support; the call will have to be optimised out by the compiler */
+#endif
+#endif
+
+G_END_DECLS

glib/gtrace.c

+/*
+ * Copyright © 2020 Endless Mobile, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Philip Withnall <withnall@endlessm.com>
+ */
+
+/*
+ * SECTION:trace
+ * @Title: Performance tracing
+ * @Short_description: Functions for measuring and tracing performance
+ *
+ * The performance tracing functions allow for the performance of code using
+ * GLib to be measured by passing metrics from the current process to an
+ * external measurement process such as `sysprof-cli` or `sysprofd`.
+ *
+ * They are designed to execute quickly, especially in the common case where no
+ * measurement process is connected. They are guaranteed to not block the caller
+ * and are guaranteed to have zero runtime cost if tracing support is disabled
+ * at configure time.
+ *
+ * Tracing information can be provided as ‘marks’ with a start time and
+ * duration; or as marks with a start time and no duration. Marks with a
+ * duration are intended to show the execution time of a piece of code. Marks
+ * with no duration are intended to show an instantaneous performance problem,
+ * such as an unexpectedly large allocation, or that a slow path has been taken
+ * in some code.
+ *
+ * |[<!-- language="C" -->
+ * gint64 begin_time_nsec G_GNUC_UNUSED;
+ *
+ * begin_time_nsec = G_TRACE_CURRENT_TIME;
+ *
+ * // some code which might take a while
+ *
+ * g_trace_mark (begin_time_nsec, G_TRACE_CURRENT_TIME - begin_time_nsec,
+ *               "GLib", "GSource.dispatch",
+ *               "%s ⇒ %s", g_source_get_name (source), need_destroy ? "destroy" : "keep");
+ * ]|
+ *
+ * The tracing API is currently internal to GLib.
+ *
+ * Since: 2.66
+ */
+
+#include "config.h"
+
+#include "gtrace-private.h"
+
+#include <stdarg.h>
+
+/*
+ * g_trace_mark:
+ * @begin_time_nsec: start time of the mark, as returned by %G_TRACE_CURRENT_TIME
+ * @duration_nsec: duration of the mark, in nanoseconds
+ * @group: name of the group for categorising this mark
+ * @name: name of the mark
+ * @message_format: format for the detailed message for the mark, in `printf()` format
+ * @...: arguments to substitute into @message_format; none of these should have
+ *    side effects
+ *
+ * Add a mark to the trace, starting at @begin_time_nsec and having length
+ * @duration_nsec (which may be zero). The @group should typically be `GLib`,
+ * and the @name should concisely describe the call site.
+ *
+ * All of the arguments to this function must not have side effects, as the
+ * entire function call may be dropped if sysprof support is not available.
+ *
+ * Since: 2.66
+ */
+void
+(g_trace_mark) (gint64       begin_time_nsec,
+                gint64       duration_nsec,
+                const gchar *group,
+                const gchar *name,
+                const gchar *message_format,
+                ...)
+{
+#ifdef HAVE_SYSPROF
+  va_list args;
+
+  va_start (args, message_format);
+  sysprof_collector_mark_vprintf (begin_time_nsec, duration_nsec, group, name, message_format, args);
+  va_end (args);
+#endif  /* HAVE_SYSPROF */
+}