drm/i915: reference count for i915_hw_contexts
Enabling PPGTT and also the need to track which context was guilty of
gpu hang (arb robustness enabling) have put pressure for struct i915_hw_context
to be more than just a placeholder for hw context state.
In order to track object lifetime properly in a multi peer usage, add reference
counting for i915_hw_context.
v2: track i915_hw_context pointers instead of using ctx_ids
(from Chris Wilson)
v3 (Ben): Get rid of do_release() and handle refcounting more compactly.
(recommended by Chis)
v4: kref_* put inside static inlines (Daniel Vetter)
remove code duplication on freeing context (Chris Wilson)
v5: idr_remove and ctx->file_priv = NULL in destroy ioctl (Chris)
This actually will cause a problem if one destroys a context and later
refers to the idea of the context (multiple contexts may have the same
id, but only 1 will exist in the idr).
v6: Strip out the request related stuff. Reworded commit message.
Got rid of do_destroy and introduced i915_gem_context_release_handle,
suggested by Chris Wilson.
v7: idr_remove can't be called inside idr_for_each (Chris Wilson)
Signed-off-by: Ben Widawsky <ben@bwidawsk.net> (v5)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> (v7)
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Squash sob lines, the patch ping-ponged between Ben and Mika
a bit ...]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index a1e8ecb..9e8c685 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -124,10 +124,10 @@
return ret;
}
-static void do_destroy(struct i915_hw_context *ctx)
+void i915_gem_context_free(struct kref *ctx_ref)
{
- if (ctx->file_priv)
- idr_remove(&ctx->file_priv->context_idr, ctx->id);
+ struct i915_hw_context *ctx = container_of(ctx_ref,
+ typeof(*ctx), ref);
drm_gem_object_unreference(&ctx->obj->base);
kfree(ctx);
@@ -145,6 +145,7 @@
if (ctx == NULL)
return ERR_PTR(-ENOMEM);
+ kref_init(&ctx->ref);
ctx->obj = i915_gem_alloc_object(dev, dev_priv->hw_context_size);
if (ctx->obj == NULL) {
kfree(ctx);
@@ -169,18 +170,18 @@
if (file_priv == NULL)
return ctx;
- ctx->file_priv = file_priv;
-
ret = idr_alloc(&file_priv->context_idr, ctx, DEFAULT_CONTEXT_ID + 1, 0,
GFP_KERNEL);
if (ret < 0)
goto err_out;
+
+ ctx->file_priv = file_priv;
ctx->id = ret;
return ctx;
err_out:
- do_destroy(ctx);
+ i915_gem_context_unreference(ctx);
return ERR_PTR(ret);
}
@@ -226,7 +227,7 @@
err_unpin:
i915_gem_object_unpin(ctx->obj);
err_destroy:
- do_destroy(ctx);
+ i915_gem_context_unreference(ctx);
return ret;
}
@@ -262,6 +263,7 @@
void i915_gem_context_fini(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
+ struct i915_hw_context *dctx = dev_priv->ring[RCS].default_context;
if (dev_priv->hw_contexts_disabled)
return;
@@ -271,9 +273,8 @@
* other code, leading to spurious errors. */
intel_gpu_reset(dev);
- i915_gem_object_unpin(dev_priv->ring[RCS].default_context->obj);
-
- do_destroy(dev_priv->ring[RCS].default_context);
+ i915_gem_object_unpin(dctx->obj);
+ i915_gem_context_unreference(dctx);
}
static int context_idr_cleanup(int id, void *p, void *data)
@@ -282,8 +283,7 @@
BUG_ON(id == DEFAULT_CONTEXT_ID);
- do_destroy(ctx);
-
+ i915_gem_context_unreference(ctx);
return 0;
}
@@ -512,8 +512,8 @@
return -ENOENT;
}
- do_destroy(ctx);
-
+ idr_remove(&ctx->file_priv->context_idr, ctx->id);
+ i915_gem_context_unreference(ctx);
mutex_unlock(&dev->struct_mutex);
DRM_DEBUG_DRIVER("HW context %d destroyed\n", args->ctx_id);