[mutter/wip/texture-purge-on-nvidia: 62/66] monitor-manager/kms: Inhibit frame clock when power save mode active

[Ray Strode <halfline src gnome org>]

commit 0d4384f3509760eda46c82b78a5dfe5b016f40b7
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Jan 2 12:41:31 2019 +0100

    monitor-manager/kms: Inhibit frame clock when power save mode active
    
    We're not going to draw anyway, and when using EGLStreams we'd hit a dead lock
    when trying to eglSwapBuffers() after a page flip failed.

 src/backends/meta-monitor-manager.c            |  3 +++
 src/backends/native/meta-gpu-kms.c             |  4 ++++
 src/backends/native/meta-monitor-manager-kms.c | 29 ++++++++++++++++++++++++++
 src/backends/native/meta-monitor-manager-kms.h |  3 +++
 4 files changed, 39 insertions(+)
---
diff --git a/src/backends/meta-monitor-manager.c b/src/backends/meta-monitor-manager.c
index 5bd34ad47..6b44c8a2b 100644
--- a/src/backends/meta-monitor-manager.c
+++ b/src/backends/meta-monitor-manager.c
@@ -332,6 +332,9 @@ power_save_mode_changed (MetaMonitorManager *manager,
       return;
     }
 
+  if (manager->power_save_mode == mode)
+    return;
+
   klass = META_MONITOR_MANAGER_GET_CLASS (manager);
   if (klass->set_power_save_mode)
     klass->set_power_save_mode (manager, mode);
diff --git a/src/backends/native/meta-gpu-kms.c b/src/backends/native/meta-gpu-kms.c
index 815caf501..94398292b 100644
--- a/src/backends/native/meta-gpu-kms.c
+++ b/src/backends/native/meta-gpu-kms.c
@@ -778,6 +778,8 @@ meta_gpu_kms_read_current (MetaGpu  *gpu,
   MetaGpuKms *gpu_kms = META_GPU_KMS (gpu);
   MetaMonitorManager *monitor_manager =
     meta_gpu_get_monitor_manager (gpu);
+  MetaMonitorManagerKms *monitor_manager_kms =
+    META_MONITOR_MANAGER_KMS (monitor_manager);
   MetaKmsResources resources;
   g_autoptr (GError) local_error = NULL;
 
@@ -795,6 +797,8 @@ meta_gpu_kms_read_current (MetaGpu  *gpu,
   gpu_kms->max_buffer_width = resources.resources->max_width;
   gpu_kms->max_buffer_height = resources.resources->max_height;
 
+  meta_monitor_manager_kms_power_save_mode_changed (monitor_manager_kms,
+                                                    META_POWER_SAVE_ON);
   monitor_manager->power_save_mode = META_POWER_SAVE_ON;
 
   /* Note: we must not free the public structures (output, crtc, monitor
diff --git a/src/backends/native/meta-monitor-manager-kms.c b/src/backends/native/meta-monitor-manager-kms.c
index 438069110..5a7178753 100644
--- a/src/backends/native/meta-monitor-manager-kms.c
+++ b/src/backends/native/meta-monitor-manager-kms.c
@@ -68,6 +68,10 @@ struct _MetaMonitorManagerKms
 
   GUdevClient *udev;
   guint uevent_handler_id;
+
+  struct {
+    gboolean frame_clock_inhibited;
+  } power_save;
 };
 
 struct _MetaMonitorManagerKmsClass
@@ -90,10 +94,33 @@ meta_monitor_manager_kms_read_edid (MetaMonitorManager *manager,
   return meta_output_kms_read_edid (output);
 }
 
+void
+meta_monitor_manager_kms_power_save_mode_changed (MetaMonitorManagerKms *manager_kms,
+                                                  MetaPowerSave          mode)
+{
+  MetaMonitorManager *manager = META_MONITOR_MANAGER (manager_kms);
+  MetaBackend *backend = meta_monitor_manager_get_backend (manager);
+  MetaBackendNative *backend_native = META_BACKEND_NATIVE (backend);
+
+  if (mode == META_POWER_SAVE_ON &&
+      manager_kms->power_save.frame_clock_inhibited)
+    {
+      meta_backend_native_thaw_frame_clock (backend_native);
+      manager_kms->power_save.frame_clock_inhibited = FALSE;
+    }
+  else if (mode != META_POWER_SAVE_ON &&
+           !manager_kms->power_save.frame_clock_inhibited)
+    {
+      meta_backend_native_freeze_frame_clock (backend_native);
+      manager_kms->power_save.frame_clock_inhibited = TRUE;
+    }
+}
+
 static void
 meta_monitor_manager_kms_set_power_save_mode (MetaMonitorManager *manager,
                                               MetaPowerSave       mode)
 {
+  MetaMonitorManagerKms *manager_kms = META_MONITOR_MANAGER_KMS (manager);
   uint64_t state;
   GList *l;
 
@@ -120,6 +147,8 @@ meta_monitor_manager_kms_set_power_save_mode (MetaMonitorManager *manager,
 
       meta_gpu_kms_set_power_save_mode (gpu_kms, state);
     }
+
+  meta_monitor_manager_kms_power_save_mode_changed (manager_kms, mode);
 }
 
 static void
diff --git a/src/backends/native/meta-monitor-manager-kms.h b/src/backends/native/meta-monitor-manager-kms.h
index fea5b63f1..9e43219f5 100644
--- a/src/backends/native/meta-monitor-manager-kms.h
+++ b/src/backends/native/meta-monitor-manager-kms.h
@@ -41,4 +41,7 @@ void meta_monitor_manager_kms_pause (MetaMonitorManagerKms *manager_kms);
 
 void meta_monitor_manager_kms_resume (MetaMonitorManagerKms *manager_kms);
 
+void meta_monitor_manager_kms_power_save_mode_changed (MetaMonitorManagerKms *manager_kms,
+                                                       MetaPowerSave          mode);
+
 #endif /* META_MONITOR_MANAGER_KMS_H */