Commit f8246cf4 authored by Chris Wilson's avatar Chris Wilson
Browse files

drm/i915/gem: Drop free_work for GEM contexts 



The free_list and worker was introduced in commit 5f09a9c8 ("drm/i915:
Allow contexts to be unreferenced locklessly"), but subsequently made
redundant by the removal of the last sleeping lock in commit 2935ed53
("drm/i915: Remove logical HW ID"). As we can now free the GEM context
immediately from any context, remove the deferral of the free_list

v2: Lift removing the context from the global list into close().

Suggested-by: default avatarMika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215152138.8158-1-chris@chris-wilson.co.uk
parent 5f22cc0b

drivers/gpu/drm/i915/gem/i915_gem_context.c

+8 −51
Original line number Diff line number Diff line
@@ -334,13 +334,12 @@ static struct i915_gem_engines *default_engines(struct i915_gem_context *ctx) 
	return e;

}



static void i915_gem_context_free(struct i915_gem_context *ctx)

void i915_gem_context_release(struct kref *ref)

{

	GEM_BUG_ON(!i915_gem_context_is_closed(ctx));

	struct i915_gem_context *ctx = container_of(ref, typeof(*ctx), ref);



	spin_lock(&ctx->i915->gem.contexts.lock);

	list_del(&ctx->link);

	spin_unlock(&ctx->i915->gem.contexts.lock);

	trace_i915_context_free(ctx);

	GEM_BUG_ON(!i915_gem_context_is_closed(ctx));



	mutex_destroy(&ctx->engines_mutex);

	mutex_destroy(&ctx->lut_mutex);
@@ -354,37 +353,6 @@ static void i915_gem_context_free(struct i915_gem_context *ctx) 
	kfree_rcu(ctx, rcu);

}



static void contexts_free_all(struct llist_node *list)

{

	struct i915_gem_context *ctx, *cn;



	llist_for_each_entry_safe(ctx, cn, list, free_link)

		i915_gem_context_free(ctx);

}



static void contexts_flush_free(struct i915_gem_contexts *gc)

{

	contexts_free_all(llist_del_all(&gc->free_list));

}



static void contexts_free_worker(struct work_struct *work)

{

	struct i915_gem_contexts *gc =

		container_of(work, typeof(*gc), free_work);



	contexts_flush_free(gc);

}



void i915_gem_context_release(struct kref *ref)

{

	struct i915_gem_context *ctx = container_of(ref, typeof(*ctx), ref);

	struct i915_gem_contexts *gc = &ctx->i915->gem.contexts;



	trace_i915_context_free(ctx);

	if (llist_add(&ctx->free_link, &gc->free_list))

		schedule_work(&gc->free_work);

}



static inline struct i915_gem_engines *

__context_engines_static(const struct i915_gem_context *ctx)

{
@@ -633,6 +601,10 @@ static void context_close(struct i915_gem_context *ctx) 
	 */

	lut_close(ctx);



	spin_lock(&ctx->i915->gem.contexts.lock);

	list_del(&ctx->link);

	spin_unlock(&ctx->i915->gem.contexts.lock);



	mutex_unlock(&ctx->mutex);



	/*
@@ -850,9 +822,6 @@ i915_gem_create_context(struct drm_i915_private *i915, unsigned int flags) 
	    !HAS_EXECLISTS(i915))

		return ERR_PTR(-EINVAL);



	/* Reap the stale contexts */

	contexts_flush_free(&i915->gem.contexts);



	ctx = __create_context(i915);

	if (IS_ERR(ctx))

		return ctx;
@@ -897,9 +866,6 @@ static void init_contexts(struct i915_gem_contexts *gc) 
{

	spin_lock_init(&gc->lock);

	INIT_LIST_HEAD(&gc->list);



	INIT_WORK(&gc->free_work, contexts_free_worker);

	init_llist_head(&gc->free_list);

}



void i915_gem_init__contexts(struct drm_i915_private *i915)
@@ -907,12 +873,6 @@ void i915_gem_init__contexts(struct drm_i915_private *i915) 
	init_contexts(&i915->gem.contexts);

}



void i915_gem_driver_release__contexts(struct drm_i915_private *i915)

{

	flush_work(&i915->gem.contexts.free_work);

	rcu_barrier(); /* and flush the left over RCU frees */

}



static int gem_context_register(struct i915_gem_context *ctx,

				struct drm_i915_file_private *fpriv,

				u32 *id)
@@ -986,7 +946,6 @@ int i915_gem_context_open(struct drm_i915_private *i915, 
void i915_gem_context_close(struct drm_file *file)

{

	struct drm_i915_file_private *file_priv = file->driver_priv;

	struct drm_i915_private *i915 = file_priv->dev_priv;

	struct i915_address_space *vm;

	struct i915_gem_context *ctx;

	unsigned long idx;
@@ -998,8 +957,6 @@ void i915_gem_context_close(struct drm_file *file) 
	xa_for_each(&file_priv->vm_xa, idx, vm)

		i915_vm_put(vm);

	xa_destroy(&file_priv->vm_xa);



	contexts_flush_free(&i915->gem.contexts);

}



int i915_gem_vm_create_ioctl(struct drm_device *dev, void *data,

drivers/gpu/drm/i915/gem/i915_gem_context.h

+0 −1
Original line number Diff line number Diff line
@@ -110,7 +110,6 @@ i915_gem_context_clear_user_engines(struct i915_gem_context *ctx) 


/* i915_gem_context.c */

void i915_gem_init__contexts(struct drm_i915_private *i915);

void i915_gem_driver_release__contexts(struct drm_i915_private *i915);



int i915_gem_context_open(struct drm_i915_private *i915,

			  struct drm_file *file);

drivers/gpu/drm/i915/gem/i915_gem_context_types.h

+0 −1
Original line number Diff line number Diff line
@@ -108,7 +108,6 @@ struct i915_gem_context { 


	/** link: place with &drm_i915_private.context_list */

	struct list_head link;

	struct llist_node free_link;



	/**

	 * @ref: reference count

drivers/gpu/drm/i915/i915_drv.h

+0 −3
Original line number Diff line number Diff line
@@ -1172,9 +1172,6 @@ struct drm_i915_private { 
		struct i915_gem_contexts {

			spinlock_t lock; /* locks list */

			struct list_head list;



			struct llist_head free_list;

			struct work_struct free_work;

		} contexts;



		/*

drivers/gpu/drm/i915/i915_gem.c

+0 −2
Original line number Diff line number Diff line
@@ -1207,8 +1207,6 @@ void i915_gem_driver_remove(struct drm_i915_private *dev_priv) 


void i915_gem_driver_release(struct drm_i915_private *dev_priv)

{

	i915_gem_driver_release__contexts(dev_priv);



	intel_gt_driver_release(&dev_priv->gt);



	intel_wa_list_free(&dev_priv->gt_wa_list);