[RFC 09/10] drm/i915: Wire up with drm controller GPU time query

From: Tvrtko Ursulin
Date: Tue Mar 14 2023 - 10:20:56 EST


From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>

Implement the drm_cgroup_ops->active_time_us callback.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
---
drivers/gpu/drm/i915/i915_driver.c | 10 ++++
drivers/gpu/drm/i915/i915_drm_client.c | 76 ++++++++++++++++++++++----
drivers/gpu/drm/i915/i915_drm_client.h | 2 +
3 files changed, 78 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index da249337c23b..e956990a9870 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -1777,6 +1777,12 @@ static const struct drm_ioctl_desc i915_ioctls[] = {
DRM_IOCTL_DEF_DRV(I915_GEM_VM_DESTROY, i915_gem_vm_destroy_ioctl, DRM_RENDER_ALLOW),
};

+#ifdef CONFIG_CGROUP_DRM
+static const struct drm_cgroup_ops i915_drm_cgroup_ops = {
+ .active_time_us = i915_drm_cgroup_get_active_time_us,
+};
+#endif
+
/*
* Interface history:
*
@@ -1805,6 +1811,10 @@ static const struct drm_driver i915_drm_driver = {
.lastclose = i915_driver_lastclose,
.postclose = i915_driver_postclose,

+#ifdef CONFIG_CGROUP_DRM
+ .cg_ops = &i915_drm_cgroup_ops,
+#endif
+
.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
.gem_prime_import = i915_gem_prime_import,
diff --git a/drivers/gpu/drm/i915/i915_drm_client.c b/drivers/gpu/drm/i915/i915_drm_client.c
index b09d1d386574..c9754cb0277f 100644
--- a/drivers/gpu/drm/i915/i915_drm_client.c
+++ b/drivers/gpu/drm/i915/i915_drm_client.c
@@ -75,7 +75,7 @@ void i915_drm_clients_fini(struct i915_drm_clients *clients)
xa_destroy(&clients->xarray);
}

-#ifdef CONFIG_PROC_FS
+#if defined(CONFIG_PROC_FS) || defined(CONFIG_CGROUP_DRM)
static const char * const uabi_class_names[] = {
[I915_ENGINE_CLASS_RENDER] = "render",
[I915_ENGINE_CLASS_COPY] = "copy",
@@ -100,22 +100,78 @@ static u64 busy_add(struct i915_gem_context *ctx, unsigned int class)
return total;
}

-static void
-show_client_class(struct seq_file *m,
- struct i915_drm_client *client,
- unsigned int class)
+static u64 get_class_active_ns(struct i915_drm_client *client,
+ unsigned int class,
+ unsigned int *capacity)
{
- const struct list_head *list = &client->ctx_list;
- u64 total = atomic64_read(&client->past_runtime[class]);
- const unsigned int capacity =
- client->clients->i915->engine_uabi_class_count[class];
struct i915_gem_context *ctx;
+ u64 total;
+
+ *capacity =
+ client->clients->i915->engine_uabi_class_count[class];
+ if (!*capacity)
+ return 0;
+
+ total = atomic64_read(&client->past_runtime[class]);

rcu_read_lock();
- list_for_each_entry_rcu(ctx, list, client_link)
+ list_for_each_entry_rcu(ctx, &client->ctx_list, client_link)
total += busy_add(ctx, class);
rcu_read_unlock();

+ return total;
+}
+#endif
+
+#ifdef CONFIG_CGROUP_DRM
+static bool supports_stats(struct drm_i915_private *i915)
+{
+ if (GRAPHICS_VER(i915) < 8)
+ return false;
+
+ /* temporary... */
+ if (intel_uc_uses_guc_submission(&to_gt(i915)->uc))
+ return false;
+
+ return true;
+}
+
+u64 i915_drm_cgroup_get_active_time_us(struct drm_file *file)
+{
+ struct drm_i915_file_private *fpriv = file->driver_priv;
+ struct i915_drm_client *client = fpriv->client;
+ unsigned int i;
+ u64 busy = 0;
+
+ if (!supports_stats(client->clients->i915))
+ return 0;
+
+ for (i = 0; i < ARRAY_SIZE(uabi_class_names); i++) {
+ unsigned int capacity;
+ u64 b;
+
+ b = get_class_active_ns(client, i, &capacity);
+ if (capacity) {
+ b = DIV_ROUND_UP_ULL(b, capacity * 1000);
+ busy += b;
+ }
+ }
+
+ return busy;
+}
+#endif
+
+#ifdef CONFIG_PROC_FS
+static void
+show_client_class(struct seq_file *m,
+ struct i915_drm_client *client,
+ unsigned int class)
+{
+ unsigned int capacity;
+ u64 total;
+
+ total = get_class_active_ns(client, class, &capacity);
+
if (capacity)
seq_printf(m, "drm-engine-%s:\t%llu ns\n",
uabi_class_names[class], total);
diff --git a/drivers/gpu/drm/i915/i915_drm_client.h b/drivers/gpu/drm/i915/i915_drm_client.h
index 69496af996d9..c8439eaa89be 100644
--- a/drivers/gpu/drm/i915/i915_drm_client.h
+++ b/drivers/gpu/drm/i915/i915_drm_client.h
@@ -65,4 +65,6 @@ void i915_drm_client_fdinfo(struct seq_file *m, struct file *f);

void i915_drm_clients_fini(struct i915_drm_clients *clients);

+u64 i915_drm_cgroup_get_active_time_us(struct drm_file *file);
+
#endif /* !__I915_DRM_CLIENT_H__ */
--
2.37.2