drm/i915: Allow contexts to be unreferenced locklessly
If we move the actual cleanup of the context to a worker, we can allow
the final free to be called from any context and avoid undue latency in
the caller.
v2: Negotiate handling the delayed contexts free by flushing the
workqueue before calling i915_gem_context_fini() and performing the final
free of the kernel context directly
v3: Flush deferred frees before new context allocations
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170620110547.15947-2-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/selftests/i915_vma.c b/drivers/gpu/drm/i915/selftests/i915_vma.c
index fb9072d..2e86ec1 100644
--- a/drivers/gpu/drm/i915/selftests/i915_vma.c
+++ b/drivers/gpu/drm/i915/selftests/i915_vma.c
@@ -186,16 +186,20 @@ static int igt_vma_create(void *arg)
goto end;
}
- list_for_each_entry_safe(ctx, cn, &contexts, link)
+ list_for_each_entry_safe(ctx, cn, &contexts, link) {
+ list_del_init(&ctx->link);
mock_context_close(ctx);
+ }
}
end:
/* Final pass to lookup all created contexts */
err = create_vmas(i915, &objects, &contexts);
out:
- list_for_each_entry_safe(ctx, cn, &contexts, link)
+ list_for_each_entry_safe(ctx, cn, &contexts, link) {
+ list_del_init(&ctx->link);
mock_context_close(ctx);
+ }
list_for_each_entry_safe(obj, on, &objects, st_link)
i915_gem_object_put(obj);
diff --git a/drivers/gpu/drm/i915/selftests/mock_context.c b/drivers/gpu/drm/i915/selftests/mock_context.c
index 243325b9..9c7c681 100644
--- a/drivers/gpu/drm/i915/selftests/mock_context.c
+++ b/drivers/gpu/drm/i915/selftests/mock_context.c
@@ -86,3 +86,12 @@ void mock_context_close(struct i915_gem_context *ctx)
i915_gem_context_put(ctx);
}
+
+void mock_init_contexts(struct drm_i915_private *i915)
+{
+ INIT_LIST_HEAD(&i915->contexts.list);
+ ida_init(&i915->contexts.hw_ida);
+
+ INIT_WORK(&i915->contexts.free_work, contexts_free_worker);
+ init_llist_head(&i915->contexts.free_list);
+}
diff --git a/drivers/gpu/drm/i915/selftests/mock_context.h b/drivers/gpu/drm/i915/selftests/mock_context.h
index 2427e5c..383941a 100644
--- a/drivers/gpu/drm/i915/selftests/mock_context.h
+++ b/drivers/gpu/drm/i915/selftests/mock_context.h
@@ -25,6 +25,8 @@
#ifndef __MOCK_CONTEXT_H
#define __MOCK_CONTEXT_H
+void mock_init_contexts(struct drm_i915_private *i915);
+
struct i915_gem_context *
mock_context(struct drm_i915_private *i915,
const char *name);
diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
index 0ddb70a..47613d2 100644
--- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c
+++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
@@ -57,6 +57,7 @@ static void mock_device_release(struct drm_device *dev)
cancel_delayed_work_sync(&i915->gt.retire_work);
cancel_delayed_work_sync(&i915->gt.idle_work);
+ flush_workqueue(i915->wq);
mutex_lock(&i915->drm.struct_mutex);
for_each_engine(engine, i915, id)
@@ -160,7 +161,7 @@ struct drm_i915_private *mock_gem_device(void)
INIT_LIST_HEAD(&i915->mm.unbound_list);
INIT_LIST_HEAD(&i915->mm.bound_list);
- ida_init(&i915->contexts.hw_ida);
+ mock_init_contexts(i915);
INIT_DELAYED_WORK(&i915->gt.retire_work, mock_retire_work_handler);
INIT_DELAYED_WORK(&i915->gt.idle_work, mock_idle_work_handler);