[v5,07/11] drm/i915: advertise available metrics via sysfs
diff mbox

Message ID 20160819140436.2116-1-robert@sixbynine.org
State New
Headers show

Commit Message

Robert Bragg Aug. 19, 2016, 2:04 p.m. UTC
Each metric set is given a sysfs entry like:

/sys/class/drm/card0/metrics/<guid>/id

This allows userspace to enumerate the specific sets that are available
for the current system. The 'id' file contains an unsigned integer that
can be used to open the associated metric set via
DRM_IOCTL_I915_PERF_OPEN. The <guid> is a globally unique ID for a
specific OA unit register configuration that can be reliably used by
userspace as a key to lookup corresponding counter meta data and
normalization equations.

The guid registry is currently maintained as part of gputop along with
the XML metric set descriptions and code generation scripts, ref:

 https://github.com/rib/gputop
 > gputop-data/guids.xml
 > scripts/update-guids.py
 > gputop-data/oa-*.xml
 > scripts/i915-perf-kernelgen.py

 $ make -C gputop-data -f Makefile.xml SYSFS=1 WHITELIST=RenderBasic

Signed-off-by: Robert Bragg <robert@sixbynine.org>
---
 drivers/gpu/drm/i915/i915_drv.c    |  5 ++++
 drivers/gpu/drm/i915/i915_drv.h    |  4 +++
 drivers/gpu/drm/i915/i915_oa_hsw.c | 45 +++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_oa_hsw.h |  4 +++
 drivers/gpu/drm/i915/i915_perf.c   | 52 ++++++++++++++++++++++++++++++++++++++
 5 files changed, 110 insertions(+)

Patch
diff mbox

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 92f668e..53df16f 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1150,6 +1150,9 @@  static void i915_driver_register(struct drm_i915_private *dev_priv)
 	if (drm_dev_register(dev, 0) == 0) {
 		i915_debugfs_register(dev_priv);
 		i915_setup_sysfs(dev);
+
+		/* Depends on sysfs having been initialized */
+		i915_perf_register(dev_priv);
 	} else
 		DRM_ERROR("Failed to register driver for userspace access!\n");
 
@@ -1186,6 +1189,8 @@  static void i915_driver_unregister(struct drm_i915_private *dev_priv)
 	acpi_video_unregister();
 	intel_opregion_unregister(dev_priv);
 
+	i915_perf_unregister(dev_priv);
+
 	i915_teardown_sysfs(&dev_priv->drm);
 	i915_debugfs_unregister(dev_priv);
 	drm_dev_unregister(&dev_priv->drm);
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 4c302cd..dd88eb1 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2115,6 +2115,8 @@  struct drm_i915_private {
 	struct {
 		bool initialized;
 
+		struct kobject *metrics_kobj;
+
 		struct mutex lock;
 		struct list_head streams;
 
@@ -3694,6 +3696,8 @@  int intel_engine_cmd_parser(struct intel_engine_cs *engine,
 /* i915_perf.c */
 extern void i915_perf_init(struct drm_i915_private *dev_priv);
 extern void i915_perf_fini(struct drm_i915_private *dev_priv);
+extern void i915_perf_register(struct drm_i915_private *dev_priv);
+extern void i915_perf_unregister(struct drm_i915_private *dev_priv);
 
 /* i915_suspend.c */
 extern int i915_save_state(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/i915_oa_hsw.c b/drivers/gpu/drm/i915/i915_oa_hsw.c
index 3e6006ec..3f9dd80 100644
--- a/drivers/gpu/drm/i915/i915_oa_hsw.c
+++ b/drivers/gpu/drm/i915/i915_oa_hsw.c
@@ -24,6 +24,8 @@ 
  *
  */
 
+#include <linux/sysfs.h>
+
 #include "i915_drv.h"
 
 enum metric_set_id {
@@ -130,3 +132,46 @@  int i915_oa_select_metric_set_hsw(struct drm_i915_private *dev_priv)
 		return -ENODEV;
 	}
 }
+
+static ssize_t
+show_render_basic_id(struct device *kdev, struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", METRIC_SET_ID_RENDER_BASIC);
+}
+
+static struct device_attribute dev_attr_render_basic_id = {
+	.attr = { .name = "id", .mode = S_IRUGO },
+	.show = show_render_basic_id,
+	.store = NULL,
+};
+
+static struct attribute *attrs_render_basic[] = {
+	&dev_attr_render_basic_id.attr,
+	NULL,
+};
+
+static struct attribute_group group_render_basic = {
+	.name = "403d8832-1a27-4aa6-a64e-f5389ce7b212",
+	.attrs =  attrs_render_basic,
+};
+
+int
+i915_perf_register_sysfs_hsw(struct drm_i915_private *dev_priv)
+{
+	int ret;
+
+	ret = sysfs_create_group(dev_priv->perf.metrics_kobj, &group_render_basic);
+	if (ret)
+		goto error_render_basic;
+
+	return 0;
+
+error_render_basic:
+	return ret;
+}
+
+void
+i915_perf_unregister_sysfs_hsw(struct drm_i915_private *dev_priv)
+{
+	sysfs_remove_group(dev_priv->perf.metrics_kobj, &group_render_basic);
+}
diff --git a/drivers/gpu/drm/i915/i915_oa_hsw.h b/drivers/gpu/drm/i915/i915_oa_hsw.h
index b618a1f..429a229 100644
--- a/drivers/gpu/drm/i915/i915_oa_hsw.h
+++ b/drivers/gpu/drm/i915/i915_oa_hsw.h
@@ -31,4 +31,8 @@  extern int i915_oa_n_builtin_metric_sets_hsw;
 
 extern int i915_oa_select_metric_set_hsw(struct drm_i915_private *dev_priv);
 
+extern int i915_perf_register_sysfs_hsw(struct drm_i915_private *dev_priv);
+
+extern void i915_perf_unregister_sysfs_hsw(struct drm_i915_private *dev_priv);
+
 #endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 7873d15..b9e3ec2 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -731,6 +731,15 @@  static int i915_oa_stream_init(struct i915_perf_stream *stream,
 	int format_size;
 	int ret;
 
+	/* If the sysfs metrics/ directory wasn't registered for some
+	 * reason then don't let userspace try their luck with config
+	 * IDs
+	 */
+	if (!dev_priv->perf.metrics_kobj) {
+		DRM_ERROR("OA metrics weren't advertised via sysfs\n");
+		return -EINVAL;
+	}
+
 	if (!(props->sample_flags & SAMPLE_OA_REPORT)) {
 		DRM_ERROR("Only OA report sampling supported\n");
 		return -EINVAL;
@@ -1353,6 +1362,49 @@  int i915_perf_open_ioctl(struct drm_device *dev, void *data,
 	return ret;
 }
 
+void i915_perf_register(struct drm_i915_private *dev_priv)
+{
+	if (!IS_HASWELL(dev_priv))
+		return;
+
+	if (!dev_priv->perf.initialized)
+		return;
+
+	/* To be sure we're synchronized with an attempted
+	 * i915_perf_open_ioctl(); considering that we register after
+	 * being exposed to userspace.
+	 */
+	mutex_lock(&dev_priv->perf.lock);
+
+	dev_priv->perf.metrics_kobj =
+		kobject_create_and_add("metrics",
+				       &dev_priv->drm.primary->kdev->kobj);
+	if (!dev_priv->perf.metrics_kobj)
+		goto exit;
+
+	if (i915_perf_register_sysfs_hsw(dev_priv)) {
+		kobject_put(dev_priv->perf.metrics_kobj);
+		dev_priv->perf.metrics_kobj = NULL;
+	}
+
+exit:
+	mutex_unlock(&dev_priv->perf.lock);
+}
+
+void i915_perf_unregister(struct drm_i915_private *dev_priv)
+{
+	if (!IS_HASWELL(dev_priv))
+		return;
+
+	if (!dev_priv->perf.metrics_kobj)
+		return;
+
+	i915_perf_unregister_sysfs_hsw(dev_priv);
+
+	kobject_put(dev_priv->perf.metrics_kobj);
+	dev_priv->perf.metrics_kobj = NULL;
+}
+
 void i915_perf_init(struct drm_i915_private *dev_priv)
 {
 	if (!IS_HASWELL(dev_priv))