Merge branch 'task-trace' into 'master'

Add some tracing to GTask

See merge request GNOME/glib!1629

gio/gtask.c

@@ -24,6 +24,7 @@
 #include "gasyncresult.h"
 #include "gcancellable.h"
 #include "glib-private.h"
+#include "gtrace-private.h"
 
 #include "glibintl.h"
 
@@ -618,6 +619,9 @@ static GSource *task_pool_manager;
 static guint64 task_wait_time;
 static gint tasks_running;
 
+static guint task_pool_max_counter;
+static guint tasks_running_counter;
+
 /* When the task pool fills up and blocks, and the program keeps
  * queueing more tasks, we will slowly add more threads to the pool
  * (in case the existing tasks are trying to queue subtasks of their
@@ -1361,6 +1365,7 @@ task_pool_manager_timeout (gpointer user_data)
 {
   g_mutex_lock (&task_pool_mutex);
   g_thread_pool_set_max_threads (task_pool, tasks_running + 1, NULL);
+  g_trace_set_int64_counter (task_pool_max_counter, tasks_running + 1);
   g_source_set_ready_time (task_pool_manager, -1);
   g_mutex_unlock (&task_pool_mutex);
 
@@ -1374,6 +1379,8 @@ g_task_thread_setup (void)
   g_mutex_lock (&task_pool_mutex);
   tasks_running++;
 
+  g_trace_set_int64_counter (tasks_running_counter, tasks_running);
+
   if (tasks_running == G_TASK_POOL_SIZE)
     task_wait_time = G_TASK_WAIT_TIME_BASE;
   else if (tasks_running > G_TASK_POOL_SIZE && tasks_running < G_TASK_WAIT_TIME_MAX_POOL_SIZE)
@@ -1394,7 +1401,10 @@ g_task_thread_cleanup (void)
   tasks_pending = g_thread_pool_unprocessed (task_pool);
 
   if (tasks_running > G_TASK_POOL_SIZE)
-    g_thread_pool_set_max_threads (task_pool, tasks_running - 1, NULL);
+    {
+      g_thread_pool_set_max_threads (task_pool, tasks_running - 1, NULL);
+      g_trace_set_int64_counter (task_pool_max_counter, tasks_running - 1);
+    }
   else if (tasks_running + tasks_pending < G_TASK_POOL_SIZE)
     g_source_set_ready_time (task_pool_manager, -1);
 
@@ -1402,6 +1412,9 @@ g_task_thread_cleanup (void)
     task_wait_time /= G_TASK_WAIT_TIME_MULTIPLIER;
 
   tasks_running--;
+
+  g_trace_set_int64_counter (tasks_running_counter, tasks_running);
+
   g_mutex_unlock (&task_pool_mutex);
   g_private_set (&task_private, GUINT_TO_POINTER (FALSE));
 }
@@ -2214,6 +2227,16 @@ g_task_class_init (GTaskClass *klass)
                           P_("Task completed"),
                           P_("Whether the task has completed yet"),
                           FALSE, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
+
+  if (G_UNLIKELY (task_pool_max_counter == 0))
+    {
+      /* We use two counters to track characteristics of the GTask thread pool.
+       * task pool max size - the value of g_thread_pool_set_max_threads()
+       * tasks running - the number of running threads
+       */
+      task_pool_max_counter = g_trace_define_int64_counter ("GIO", "task pool max size", "Maximum number of threads allowed in the GTask thread pool; see g_thread_pool_set_max_threads()");
+      tasks_running_counter = g_trace_define_int64_counter ("GIO", "tasks running", "Number of currently running tasks in the GTask thread pool");
+    }
 }
 
 static gpointer

gio/meson.build

@@ -577,6 +577,7 @@ gio_sources = files(
   'gzlibdecompressor.c',
   'glistmodel.c',
   'gliststore.c',
+  '../glib/gtrace.c',
 )
 
 gio_sources += appinfo_sources
@@ -791,7 +792,7 @@ libgio = library('gio-2.0',
   #  '$(gio_win32_res_ldflag)',
   dependencies : [libz_dep, libdl_dep, libmount_dep, libglib_dep,
                   libgobject_dep, libgmodule_dep, selinux_dep, xattr_dep,
-                  platform_deps, network_libs],
+                  platform_deps, network_libs, libsysprof_capture_dep],
   c_args : gio_c_args,
   objc_args : gio_c_args,
   # intl.lib is not compatible with SAFESEH

glib/gtrace-private.h

@@ -23,8 +23,7 @@
 #include <sysprof-capture.h>
 #endif
 
-#include "gmem.h"
-#include "gmacros.h"
+#include "glib.h"
 
 G_BEGIN_DECLS
 
@@ -67,4 +66,15 @@ void (g_trace_mark) (gint64       begin_time_nsec,
 #endif
 #endif
 
+guint   (g_trace_define_int64_counter) (const char *group,
+                                        const char *name,
+                                        const char *description);
+void    (g_trace_set_int64_counter)    (guint       id,
+                                        gint64      value);
+
+#ifndef HAVE_SYSPROF
+#define g_trace_define_int64_counter(g, n, d) ((guint) -1)
+#define g_trace_set_int64_counter(i,v)
+#endif
+
 G_END_DECLS

glib/gtrace.c

@@ -96,3 +96,82 @@ void
   va_end (args);
 #endif  /* HAVE_SYSPROF */
 }
+
+/*
+ * g_trace_define_int64_counter:
+ * @group: name of the group for categorising this counter
+ * @name: name of the counter
+ * @description: description for the counter
+ *
+ * Defines a new counter with integer values.
+ *
+ * The name should be unique within all counters defined with
+ * the same @group. The description will be shown in the sysprof UI.
+ *
+ * To add entries for this counter to a trace, use
+ * g_trace_set_int64_counter().
+ *
+ * Returns: ID of the counter, for use with g_trace_set_int64_counter(),
+ *     guaranteed to never be zero
+ *
+ * Since: 2.68
+ */
+guint
+(g_trace_define_int64_counter) (const char *group,
+                                const char *name,
+                                const char *description)
+{
+#ifdef HAVE_SYSPROF
+  SysprofCaptureCounter counter;
+
+  counter.id = sysprof_collector_request_counters (1);
+
+  /* sysprof not enabled? */
+  if (counter.id == 0)
+    return (guint) -1;
+
+  counter.type = SYSPROF_CAPTURE_COUNTER_INT64;
+  counter.value.v64 = 0;
+  g_strlcpy (counter.category, group, sizeof counter.category);
+  g_strlcpy (counter.name, name, sizeof counter.name);
+  g_strlcpy (counter.description, description, sizeof counter.description);
+
+  sysprof_collector_define_counters (&counter, 1);
+
+  g_assert (counter.id != 0);
+
+  return counter.id;
+#else
+  return (guint) -1;
+#endif
+}
+
+/*
+ * g_trace_set_int64_counter:
+ * @id: ID of the counter
+ * @val: the value to set the counter to
+ *
+ * Adds a counter value to a trace.
+ *
+ * The ID must be obtained via g_trace_define_int64_counter()
+ * before using this function.
+ *
+ * Since: 2.68
+ */
+void
+(g_trace_set_int64_counter) (guint  id,
+                             gint64 val)
+{
+#ifdef HAVE_SYSPROF
+  SysprofCaptureCounterValue value;
+
+  g_return_if_fail (id != 0);
+
+  /* Ignore setting the counter if we failed to define it in the first place. */
+  if (id == (guint) -1)
+    return;
+
+  value.v64 = val;
+  sysprof_collector_set_counters (&id, &value, 1);
+#endif
+}

glib/meson.build

@@ -8,7 +8,7 @@ if not use_system_pcre
 endif
 
 # libsysprof-capture support
-libsysprof_capture_dep = dependency('sysprof-capture-4',
+libsysprof_capture_dep = dependency('sysprof-capture-4', version: '>= 3.38.0',
   required: get_option('sysprof'),
   default_options: [
     'enable_examples=false',

subprojects/sysprof.wrap

@@ -1,5 +1,5 @@
 [wrap-git]
 directory=sysprof
 url=https://gitlab.gnome.org/GNOME/sysprof.git
-revision=6b1cd7a722fcebae1ac392562c47957477ade8bf
+revision=3.38.0
 depth=1