drm/lima: add usage counting method to ctx_mgr

lima maintains a context manager per drm_file, similar to amdgpu.
In order to account for the complete usage per drm_file, all of the
associated contexts need to be considered.
Previously released contexts also need to be accounted for but their
drm_sched_entity info is gone once they get released, so account for it
in the ctx_mgr.
Signed-off-by: Erico Nunes <nunes.erico@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230312233052.21095-2-nunes.erico@gmail.com

drivers/gpu/drm/lima/lima_ctx.c

@@ -15,6 +15,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
 	if (!ctx)
 		return -ENOMEM;
 	ctx->dev = dev;
+	ctx->mgr = mgr;
 	kref_init(&ctx->refcnt);
 
 	for (i = 0; i < lima_pipe_num; i++) {
@@ -42,10 +43,17 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
 static void lima_ctx_do_release(struct kref *ref)
 {
 	struct lima_ctx *ctx = container_of(ref, struct lima_ctx, refcnt);
+	struct lima_ctx_mgr *mgr = ctx->mgr;
 	int i;
 
-	for (i = 0; i < lima_pipe_num; i++)
+	for (i = 0; i < lima_pipe_num; i++) {
+		struct lima_sched_context *context = &ctx->context[i];
+		struct drm_sched_entity *entity = &context->base;
+
+		mgr->elapsed_ns[i] += entity->elapsed_ns;
+
 		lima_sched_context_fini(ctx->dev->pipe + i, ctx->context + i);
+	}
 	kfree(ctx);
 }
 
@@ -99,3 +107,23 @@ void lima_ctx_mgr_fini(struct lima_ctx_mgr *mgr)
 	xa_destroy(&mgr->handles);
 	mutex_destroy(&mgr->lock);
 }
+
+void lima_ctx_mgr_usage(struct lima_ctx_mgr *mgr, u64 usage[lima_pipe_num])
+{
+	struct lima_ctx *ctx;
+	unsigned long id;
+
+	for (int i = 0; i < lima_pipe_num; i++)
+		usage[i] = mgr->elapsed_ns[i];
+
+	mutex_lock(&mgr->lock);
+	xa_for_each(&mgr->handles, id, ctx) {
+		for (int i = 0; i < lima_pipe_num; i++) {
+			struct lima_sched_context *context = &ctx->context[i];
+			struct drm_sched_entity *entity = &context->base;
+
+			usage[i] += entity->elapsed_ns;
+		}
+	}
+	mutex_unlock(&mgr->lock);
+}

drivers/gpu/drm/lima/lima_ctx.h

@@ -12,6 +12,7 @@
 struct lima_ctx {
 	struct kref refcnt;
 	struct lima_device *dev;
+	struct lima_ctx_mgr *mgr;
 	struct lima_sched_context context[lima_pipe_num];
 	atomic_t guilty;
 
@@ -23,6 +24,7 @@ struct lima_ctx {
 struct lima_ctx_mgr {
 	struct mutex lock;
 	struct xarray handles;
+	u64 elapsed_ns[lima_pipe_num];
 };
 
 int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id);
@@ -31,5 +33,6 @@ struct lima_ctx *lima_ctx_get(struct lima_ctx_mgr *mgr, u32 id);
 void lima_ctx_put(struct lima_ctx *ctx);
 void lima_ctx_mgr_init(struct lima_ctx_mgr *mgr);
 void lima_ctx_mgr_fini(struct lima_ctx_mgr *mgr);
+void lima_ctx_mgr_usage(struct lima_ctx_mgr *mgr, u64 usage[lima_pipe_num]);
 
 #endif