[RFC 7/8] drm/i915: Expose client engine utilisation via fdinfo

[Tvrtko Ursulin]

From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Similar to AMD commit
874442541133 ("drm/amdgpu: Add show_fdinfo() interface"), using the
infrastructure added in previous patches, we add basic client info
and GPU engine utilisation for i915.

Example of the output:

  pos:    0
  flags:  0100002
  mnt_id: 21
  drm-driver: i915
  drm-pdev:   0000:00:02.0
  drm-client-id:      7
  drm-engine-render:  9288864723 ns
  drm-engine-copy:    2035071108 ns
  drm-engine-video:   0 ns
  drm-engine-video-enhance:   0 ns

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: David M Nieto <David.Nieto at amd.com>
Cc: Christian König <christian.koenig at amd.com>
Cc: Daniel Vetter <daniel at ffwll.ch>
---
 drivers/gpu/drm/i915/i915_drm_client.c | 73 ++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_drm_client.h |  4 ++
 drivers/gpu/drm/i915/i915_drv.c        |  3 ++
 3 files changed, 80 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drm_client.c b/drivers/gpu/drm/i915/i915_drm_client.c
index 1e5db7753276..a8338ca19748 100644
--- a/drivers/gpu/drm/i915/i915_drm_client.c
+++ b/drivers/gpu/drm/i915/i915_drm_client.c
@@ -9,6 +9,11 @@
 
 #include <drm/drm_print.h>
 
+#include <uapi/drm/i915_drm.h>
+
+#include "gem/i915_gem_context.h"
+#include "gt/intel_engine_user.h"
+
 #include "i915_drm_client.h"
 #include "i915_drv.h"
 #include "i915_gem.h"
@@ -168,3 +173,71 @@ void i915_drm_clients_fini(struct i915_drm_clients *clients)
 
 	xa_destroy(&clients->xarray);
 }
+
+#ifdef CONFIG_PROC_FS
+static const char * const uabi_class_names[] = {
+	[I915_ENGINE_CLASS_RENDER] = "render",
+	[I915_ENGINE_CLASS_COPY] = "copy",
+	[I915_ENGINE_CLASS_VIDEO] = "video",
+	[I915_ENGINE_CLASS_VIDEO_ENHANCE] = "video-enhance",
+};
+
+static u64 busy_add(struct i915_gem_context *ctx, unsigned int class)
+{
+	struct i915_gem_engines_iter it;
+	struct intel_context *ce;
+	u64 total = 0;
+
+	for_each_gem_engine(ce, rcu_dereference(ctx->engines), it) {
+		if (ce->engine->uabi_class != class)
+			continue;
+
+		total += intel_context_get_total_runtime_ns(ce);
+	}
+
+	return total;
+}
+
+static void
+show_client_class(struct seq_file *m,
+		  struct i915_drm_client *client,
+		  unsigned int class)
+{
+	const struct list_head *list = &client->ctx_list;
+	u64 total = atomic64_read(&client->past_runtime[class]);
+	struct i915_gem_context *ctx;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(ctx, list, client_link)
+		total += busy_add(ctx, class);
+	rcu_read_unlock();
+
+	return seq_printf(m, "drm-engine-%s:\t%llu ns\n",
+			  uabi_class_names[class], total);
+}
+
+void i915_drm_client_fdinfo(struct seq_file *m, struct file *f)
+{
+	struct drm_file *file = f->private_data;
+	struct drm_i915_file_private *file_priv = file->driver_priv;
+	struct drm_i915_private *i915 = file_priv->dev_priv;
+	struct i915_drm_client *client = file_priv->client;
+	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
+	unsigned int i;
+
+	seq_puts(m, "drm-driver:\ti915\n");
+	seq_printf(m, "drm-pdev:\t%04x:%02x:%02x.%d\n",
+		   pci_domain_nr(pdev->bus), pdev->bus->number,
+		   PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
+
+	seq_printf(m, "drm-client-id:\t%u\n", client->id);
+	rcu_read_lock();
+	seq_printf(m, "drm-client-name:\t%s\n", i915_drm_client_name(client));
+	seq_printf(m, "drm-client-pid:\t%u\n",
+		   pid_nr(i915_drm_client_pid(client)));
+	rcu_read_unlock();
+
+	for (i = 0; i < ARRAY_SIZE(uabi_class_names); i++)
+		show_client_class(m, client, i);
+}
+#endif
diff --git a/drivers/gpu/drm/i915/i915_drm_client.h b/drivers/gpu/drm/i915/i915_drm_client.h
index b2b69d6985e4..9885002433a0 100644
--- a/drivers/gpu/drm/i915/i915_drm_client.h
+++ b/drivers/gpu/drm/i915/i915_drm_client.h
@@ -98,6 +98,10 @@ i915_drm_client_pid(const struct i915_drm_client *client)
 	return __i915_drm_client_name(client)->pid;
 }
 
+#ifdef CONFIG_PROC_FS
+void i915_drm_client_fdinfo(struct seq_file *m, struct file *f);
+#endif
+
 void i915_drm_clients_fini(struct i915_drm_clients *clients);
 
 #endif /* !__I915_DRM_CLIENT_H__ */
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 8247dcc7586e..17712a490378 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1706,6 +1706,9 @@ static const struct file_operations i915_driver_fops = {
 	.read = drm_read,
 	.compat_ioctl = i915_ioc32_compat_ioctl,
 	.llseek = noop_llseek,
+#ifdef CONFIG_PROC_FS
+	.show_fdinfo = i915_drm_client_fdinfo,
+#endif
 };
 
 static int
-- 
2.30.2