[sysprof] governor: add source to toggle CPU governer while running

[Christian Hergert <chergert src gnome org>]

commit 1254b161402f17f3fa64d0f47436411e2f5f7501
Author: Christian Hergert <chergert redhat com>
Date:   Fri Jun 14 08:03:59 2019 -0700

    governor: add source to toggle CPU governer while running

 src/libsysprof/meson.build               |   2 +
 src/libsysprof/sysprof-governor-source.c | 266 +++++++++++++++++++++++++++++++
 src/libsysprof/sysprof-governor-source.h |  40 +++++
 src/libsysprof/sysprof.h                 |   1 +
 4 files changed, 309 insertions(+)
---
diff --git a/src/libsysprof/meson.build b/src/libsysprof/meson.build
index 806b86a..9945852 100644
--- a/src/libsysprof/meson.build
+++ b/src/libsysprof/meson.build
@@ -9,6 +9,7 @@ libsysprof_public_sources = [
   'sysprof-capture-symbol-resolver.c',
   'sysprof-elf-symbol-resolver.c',
   'sysprof-gjs-source.c',
+  'sysprof-governor-source.c',
   'sysprof-hostinfo-source.c',
   'sysprof-jitmap-symbol-resolver.c',
   'sysprof-kernel-symbol.c',
@@ -35,6 +36,7 @@ libsysprof_public_headers = [
   'sysprof-capture-symbol-resolver.h',
   'sysprof-elf-symbol-resolver.h',
   'sysprof-gjs-source.h',
+  'sysprof-governor-source.h',
   'sysprof-hostinfo-source.h',
   'sysprof-jitmap-symbol-resolver.h',
   'sysprof-kernel-symbol.h',
diff --git a/src/libsysprof/sysprof-governor-source.c b/src/libsysprof/sysprof-governor-source.c
new file mode 100644
index 0000000..ca33f2d
--- /dev/null
+++ b/src/libsysprof/sysprof-governor-source.c
@@ -0,0 +1,266 @@
+/* sysprof-governor-source.c
+ *
+ * Copyright 2019 Christian Hergert <chergert redhat com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#define G_LOG_DOMAIN "sysprof-governor-source"
+
+#include "config.h"
+
+#include "sysprof-governor-source.h"
+#include "sysprof-helpers.h"
+
+struct _SysprofGovernorSource
+{
+  GObject parent_instance;
+  gchar *old_governor;
+  guint disable_governor : 1;
+};
+
+enum {
+  PROP_0,
+  PROP_DISABLE_GOVERNOR,
+  N_PROPS
+};
+
+static void source_iface_init (SysprofSourceInterface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (SysprofGovernorSource, sysprof_governor_source, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (SYSPROF_TYPE_SOURCE, source_iface_init))
+
+static GParamSpec *properties [N_PROPS];
+
+static void
+sysprof_governor_source_finalize (GObject *object)
+{
+  SysprofGovernorSource *self = (SysprofGovernorSource *)object;
+
+  g_clear_pointer (&self->old_governor, g_free);
+
+  G_OBJECT_CLASS (sysprof_governor_source_parent_class)->finalize (object);
+}
+
+static void
+sysprof_governor_source_get_property (GObject    *object,
+                                      guint       prop_id,
+                                      GValue     *value,
+                                      GParamSpec *pspec)
+{
+  SysprofGovernorSource *self = SYSPROF_GOVERNOR_SOURCE (object);
+
+  switch (prop_id)
+    {
+    case PROP_DISABLE_GOVERNOR:
+      g_value_set_boolean (value, sysprof_governor_source_get_disable_governor (self));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+sysprof_governor_source_set_property (GObject      *object,
+                                      guint         prop_id,
+                                      const GValue *value,
+                                      GParamSpec   *pspec)
+{
+  SysprofGovernorSource *self = SYSPROF_GOVERNOR_SOURCE (object);
+
+  switch (prop_id)
+    {
+    case PROP_DISABLE_GOVERNOR:
+      sysprof_governor_source_set_disable_governor (self, g_value_get_boolean (value));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+sysprof_governor_source_class_init (SysprofGovernorSourceClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->finalize = sysprof_governor_source_finalize;
+  object_class->get_property = sysprof_governor_source_get_property;
+  object_class->set_property = sysprof_governor_source_set_property;
+
+  properties [PROP_DISABLE_GOVERNOR] =
+    g_param_spec_boolean ("disable-governor",
+                          "Disable Governor",
+                          "Disable Governor",
+                          TRUE,
+                          (G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS));
+  
+  g_object_class_install_properties (object_class, N_PROPS, properties);
+}
+
+static void
+sysprof_governor_source_init (SysprofGovernorSource *self)
+{
+  self->disable_governor = TRUE;
+}
+
+SysprofSource *
+sysprof_governor_source_new (void)
+{
+  return g_object_new (SYSPROF_TYPE_GOVERNOR_SOURCE, NULL);
+}
+
+gboolean
+sysprof_governor_source_get_disable_governor (SysprofGovernorSource *self)
+{
+  g_return_val_if_fail (SYSPROF_IS_GOVERNOR_SOURCE (self), FALSE);
+
+  return self->disable_governor;
+}
+
+void
+sysprof_governor_source_set_disable_governor (SysprofGovernorSource *self,
+                                              gboolean               disable_governor)
+{
+  g_return_if_fail (SYSPROF_IS_GOVERNOR_SOURCE (self));
+
+  disable_governor = !!disable_governor;
+
+  if (disable_governor != self->disable_governor)
+    {
+      self->disable_governor = disable_governor;
+      g_object_notify_by_pspec (G_OBJECT (self), properties [PROP_DISABLE_GOVERNOR]);
+    }
+}
+
+static void
+sysprof_governor_source_serialize (SysprofSource *source,
+                                   GKeyFile      *keyfile,
+                                   const gchar   *group)
+{
+  SysprofGovernorSource *self = (SysprofGovernorSource *)source;
+
+  g_assert (SYSPROF_IS_GOVERNOR_SOURCE (self));
+  g_assert (keyfile != NULL);
+  g_assert (group != NULL);
+
+  g_key_file_set_boolean (keyfile, group, "disable-governor", self->disable_governor);
+}
+
+static void
+sysprof_governor_source_deserialize (SysprofSource *source,
+                                     GKeyFile      *keyfile,
+                                     const gchar   *group)
+{
+  SysprofGovernorSource *self = (SysprofGovernorSource *)source;
+
+  g_assert (SYSPROF_IS_GOVERNOR_SOURCE (self));
+  g_assert (keyfile != NULL);
+  g_assert (group != NULL);
+
+  sysprof_governor_source_set_disable_governor (self,
+                                                g_key_file_get_boolean (keyfile, group, "disable-governor", 
NULL));
+}
+
+static void
+disable_governor_cb (GObject      *object,
+                     GAsyncResult *result,
+                     gpointer      user_data)
+{
+  SysprofHelpers *helpers = (SysprofHelpers *)object;
+  g_autoptr(SysprofGovernorSource) self = user_data;
+  g_autoptr(GError) error = NULL;
+  g_autofree gchar *old_governor = NULL;
+
+  g_assert (SYSPROF_IS_HELPERS (helpers));
+  g_assert (G_IS_ASYNC_RESULT (result));
+  g_assert (SYSPROF_IS_GOVERNOR_SOURCE (self));
+
+  if (!sysprof_helpers_set_governor_finish (helpers, result, &old_governor, &error))
+    g_warning ("Failed to change governor: %s", error->message);
+  else
+    self->old_governor = g_steal_pointer (&old_governor);
+
+  sysprof_source_emit_ready (SYSPROF_SOURCE (self));
+}
+
+static void
+enable_governor_cb (GObject      *object,
+                    GAsyncResult *result,
+                    gpointer      user_data)
+{
+  SysprofHelpers *helpers = (SysprofHelpers *)object;
+  g_autoptr(SysprofGovernorSource) self = user_data;
+  g_autoptr(GError) error = NULL;
+  g_autofree gchar *old_governor = NULL;
+
+  g_assert (SYSPROF_IS_HELPERS (helpers));
+  g_assert (G_IS_ASYNC_RESULT (result));
+  g_assert (SYSPROF_IS_GOVERNOR_SOURCE (self));
+
+  if (!sysprof_helpers_set_governor_finish (helpers, result, &old_governor, &error))
+    g_warning ("Failed to change governor: %s", error->message);
+
+  g_clear_pointer (&self->old_governor, g_free);
+
+  sysprof_source_emit_finished (SYSPROF_SOURCE (self));
+}
+
+static void
+sysprof_governor_source_prepare (SysprofSource *source)
+{
+  SysprofGovernorSource *self = (SysprofGovernorSource *)source;
+  SysprofHelpers *helpers = sysprof_helpers_get_default ();
+
+  g_assert (SYSPROF_IS_GOVERNOR_SOURCE (self));
+
+  if (!self->disable_governor)
+    sysprof_source_emit_ready (source);
+  else
+    sysprof_helpers_set_governor_async (helpers,
+                                        "performance",
+                                        NULL,
+                                        disable_governor_cb,
+                                        g_object_ref (self));
+}
+
+static void
+sysprof_governor_source_stop (SysprofSource *source)
+{
+  SysprofGovernorSource *self = (SysprofGovernorSource *)source;
+  SysprofHelpers *helpers = sysprof_helpers_get_default ();
+
+  g_assert (SYSPROF_IS_GOVERNOR_SOURCE (self));
+
+  if (self->old_governor == NULL)
+    sysprof_source_emit_finished (source);
+  else
+    sysprof_helpers_set_governor_async (helpers,
+                                        self->old_governor,
+                                        NULL,
+                                        enable_governor_cb,
+                                        g_object_ref (self));
+}
+
+static void
+source_iface_init (SysprofSourceInterface *iface)
+{
+  iface->deserialize = sysprof_governor_source_deserialize;
+  iface->prepare = sysprof_governor_source_prepare;
+  iface->serialize = sysprof_governor_source_serialize;
+  iface->stop = sysprof_governor_source_stop;
+}
diff --git a/src/libsysprof/sysprof-governor-source.h b/src/libsysprof/sysprof-governor-source.h
new file mode 100644
index 0000000..7796888
--- /dev/null
+++ b/src/libsysprof/sysprof-governor-source.h
@@ -0,0 +1,40 @@
+/* sysprof-governor-source.h
+ *
+ * Copyright 2019 Christian Hergert <chergert redhat com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include "sysprof-source.h"
+
+G_BEGIN_DECLS
+
+#define SYSPROF_TYPE_GOVERNOR_SOURCE (sysprof_governor_source_get_type())
+
+SYSPROF_AVAILABLE_IN_ALL
+G_DECLARE_FINAL_TYPE (SysprofGovernorSource, sysprof_governor_source, SYSPROF, GOVERNOR_SOURCE, GObject)
+
+SYSPROF_AVAILABLE_IN_ALL
+SysprofSource *sysprof_governor_source_new                  (void);
+SYSPROF_AVAILABLE_IN_ALL
+gboolean       sysprof_governor_source_get_disable_governor (SysprofGovernorSource *self);
+SYSPROF_AVAILABLE_IN_ALL
+void           sysprof_governor_source_set_disable_governor (SysprofGovernorSource *self,
+                                                             gboolean               disable_governor);
+
+G_END_DECLS
diff --git a/src/libsysprof/sysprof.h b/src/libsysprof/sysprof.h
index 10b38b2..1a00bc6 100644
--- a/src/libsysprof/sysprof.h
+++ b/src/libsysprof/sysprof.h
@@ -30,6 +30,7 @@ G_BEGIN_DECLS
 # include "sysprof-capture-symbol-resolver.h"
 # include "sysprof-elf-symbol-resolver.h"
 # include "sysprof-gjs-source.h"
+# include "sysprof-governor-source.h"
 # include "sysprof-jitmap-symbol-resolver.h"
 # include "sysprof-kernel-symbol-resolver.h"
 # include "sysprof-kernel-symbol.h"